Loading...
HomeMy WebLinkAbout1997-135 Ashland Creek Flood Restoration - DRAFT CITY OF ASHLAND ti 4~~ Of Administration ~--v a = Office of the City Administrator ; 4`Si oR c + MEMORANDUM GO~ DATE: November 4, 1997 TO: Honorable Mayor and City Council FROM: Greg Scoles, Interim City Administrat RE: ASHLAND CREEK FLOOD RESTORATION PROJECT Enclosed is a copy of the draft Final Report for the Ashland Creek Flood Restoration Project. The Otak project team is scheduled to make a presentation regarding the results of the draft report at the regularly scheduled council meeting on November 18. 1 am providing you with a copy of the draft report to give you time to review it prior to the meeting. Please give me a call if you have any questions. Copies of the report have been distributed as follows: Ashland Library, The Forest Service, Headwaters, Southern Oregon University and there is one copy available in Administration for reference. Attachment (1) Ashland Creek Flood Restoration Project liry, yR • F 1•, I f l a 9 i BtiOtak, Inc., Lake Oswego, Oregon Fishman Environmental Services, Portland, Oregon CDA Consulting Group, Portland, Oregon Marquess and Associates, Medford, Oregon November 3, 1997 November 3, 1997 Mr. Greg Scoles, Interim City Administrator City of Ashland 20 East Main Street Ashland, OR 97520-1814 Re: Transmittal of Draft Final Report - Ashland Creek Flood Restoration Project - Otak Project No. L7844.W02 Dear Greg: Enclosed for your review and distribution to interested parties are 25 copies of the draft final report for the Ashland Creek Flood Restoration Project. This report represents the concerted efforts of the entire Otak project team and incorporates to the maximum extent possible the input we have received from concerned citizens and City staff. Our basic approach to the development of this report was to use the best scientific and engineering methods available, and to prepare our findings based on what the data and modeling results tell us. We understand that in a dynamic, vital community such as Ashland, it will not be possible to please everyone with our results and recommendations, but we also understand that this report will really only be the starting point for making local decisions regarding how the City of Ashland manages the flooding problem on Ashland Creek. We have greatly enjoyed working on this project, and the opportunity it has given us to work with the staff and citizens of the City of Ashland. We look forward to presenting the results of this report to the City Council at their meeting on November 18, 1997. Sincerely, Otak, Incorporated v Lawrence M. Magura 4 Project Manager LMM:vab enclosure ARCHITECTURE 17355 sw boones ferry road ENGINEERING lake Oswego, Oregon 97035-5217 LANDSCAPE ARCHITECTURE (503) 635-3618 PLANNING fax (503) 635-5395 SURVEYING & MAPPING P:\PROJECT\7800\7844\FLDREPOR\COVERLTR.N03 URBAN DESIGN Table of Contents Ashland Creek Flood Restoration Project Final Report Page Project Overview I Project Background 1 The New Year's Day Flood 1 Ashland Creek's History of Flooding 3 The Surrounding Landscape of Ashland Creek 3 The Ashland Creek Flood Restoration Project 4 Executive Summary 5 Data Collection 5 Hydrologic Study 6 Hydraulic Study and Modeling 6 Environmental Studies 7 Public Involvement Process 7 Early Action Items 8 Recommendations 10 1: Flood Control 10 2: Flood Management Plan 12 3: Flood Design Standard and Improvements 14 4: Habitat and the Environment 15 5: Aesthetic Considerations and Community Character 20 APPENDICES - REPORTS AND FINDINGS APPENDIX ONE The Public Involvement Process APPENDIX TWO Ashland Creek Hydrologic Investigation APPENDIX THREE Ashland Creek Hydraulic Investigation APPENDIX FOUR, Environmental Report APPENDIX FIVE Summary Report of Early Action Items FINALRFT.TOC PROJECT OVERVIEW PROJECT BACKGROUND The New Year's Day Flood of 1997 caused severe damage to Lithia Park and to private businesses located along the Plaza and Calle Guanajuato areas of the City of Ashland. This flood has been estimated by the Otak team to be about a 25-year event. Through research, study of the creek, survey of high water marks, and collection of detailed eye witness accounts and anecdotal information, the Otak team pulled together a clearer picture of the New Year's Day flood scenario. The New Year's Day Flood Ashland and vicinity had received heavier than average precipitation during the month of December 1996, with rain at lower elevations and snow at higher elevations. More than 6.6 inches of rain fell on the city between December 20, 1996 and January 3, 1997. On the morning of December 31, 1996, the City received a warning from the National Weather Service that heavy rain and a sharp rise in the freezing level were on the way. A meeting of key City staff members was held, and a series of flood-fighting emergency measures was begun. At that time, Ashland Creek was running high, but was still within its banks. The Ashland Creek watershed consists of steep terrain and dense stands of fir and pine growing on decomposed granite soils. The gradient of the Creek is high, which means that runoff is quickly conveyed to the lower reaches of the basin. Under the heavy runoff conditions that occurred on New Year's Day, the watershed experienced many slope failures and landslides, particularly in the narrow creek bottoms of the upper watershed. These landslides deposited large volumes of downed logs, decomposed granite sand, and other debris into the Creek channel. This created a series of localized blockages that temporarily plugged the channel until sufficient water accumulated behind the blockages to mobilize the mass. By midday on the 31st, localized bank failures were reported in several locations along the creek, and some of the pedestrian bridges in Lithia Park began to be washed away. Most of the flow was confined to the creek channel and the immediately adjacent overbank areas. By late afternoon, water began running down Winburn Way past Pioneer Hall and Hillah Temple. Several large trees that toppled into the creek were washed downstream until they became entangled in the cantilevered deck in the Calle Guanajuato. By nightfall, other debris had become entrapped, and a growing backwater was created. This allowed suspended sediment to be deposited upstream of the blockage, toward the Winburn Way culvert. Ashland Creek Flood Restoration Project - Final Report 1 Otak P: \ PROJECT \ 7800 \ 7844 \ FLDREPOR \ REPORT.030 The Winburn Way culvert had been running at capacity, with some additional flow bypassing the culvert along the west side of the creek channel. Sometime after midnight on the 31st, the culvert became almost completely blocked, and flow in the creek continued to increase with the additional rainfall and snowmelt. Significant flow started coming through the Plaza area after 2 a.m. on New Year's Day, past the door of City Hall. Businesses located in the historic Plaza area in front of City Hall were inundated. Most of this flow re-entered the creek channel at Bluebird Park, where a deteriorated retaining wall on Water Street eventually collapsed. Some flow continued down Water Street for several blocks. By dawn on New Year's Day, there was substantial flow in the Plaza, Calle Guanajuato, and the creek. Because so much water had left the creek channel upstream of the Winburn Way culvert to flow through the Plaza, when the flood peaked sometime on New Year's Day, considerable channel capacity remained in Ashland Creek in the vicinity of the Calle. Significant flow continued through the Plaza area until late in the day on January 2, 1997, when the culvert headwall was demolished and a bypass channel was completed by the City where the "Arizona crossing" is today, and flow gradually returned to the creek channel. Inside downtown, the effects of the flood were dramatic. The combined onslaught of erosion and deposition devastated Lithia Park, the crown jewel of the community and an immense source of civic pride. Lawns, picnic grounds, landscaping, pathways, playgrounds, and footbridges were damaged, dramatically transforming the park. Businesses along the Plaza and Calle Guanajuato suffered hundreds of thousands of dollars in flood damage and lost revenue. Below Main Street, flood water rushing out of the Plaza swept into Bluebird Park, causing the collapse of a retaining wall and heavy damage to the Rogue Brewery. Less damage occurred at other locations below Main Street as far downstream as Hersey Street. All along the creek corridor, from the band shell to Hersey Street, a distance of slightly more than one mile, dozens of trees were undercut and left standing in a precarious condition. Some trees were washed away by flood waters. Dozens more suffered extensive bark abrasions, leaving them vulnerable to insect infestation. Before the 1997 flood, the Ashland Creek corridor contained small amounts of riparian vegetation, such as alders. The flood scoured out the Creek and left behind rocky debris. The riparian zone was washed out and many of the streamside plants were damaged or destroyed. Trees were knocked over; some may need removal because soil was washed out from their roots; and others have become diseased because of flood damage. The major short-term effect of the New Year's Day flood was the shutdown of services for ten days because of temporary flood damage to the water and wastewater treatment plants. Citizens relied on portable toilets and water trucked to the city during the Ashland Creek Flood Restoration Project - Final Report 2 Otak P:\PROJECT\7800\ 7844\FLDREPOR\REPORT.030 period that city services were not functioning. Because no one in Ashland had water or sewer service for almost two weeks, the flood affected every person in the community, and the whole community became involved with cleanup efforts. Damages to the city were estimated at around 11 million dollars. Ashland Creek's History of Flooding Throughout the past fifty years, Ashland Creek has had a history of several significant flood events. The full effects of earlier floods are difficult to assess because the city does not have records as thorough as those compiled after the 1997 flood for the city's Federal Disaster application. However, each of the historic floods was major, and, like the 1997 flood, was probably in the range of a 25- to 50-year event. As the city has developed, the damage from floods has increased. • During the 1974 flood, sewer and water service was shut down as it was during the 1997 flood. The Forest Service estimated that 1974 debris flows were roughly equivalent to flows in 1997. More culverts on Forest Service roads were destroyed in 1974 than in 1997. Some of the culverts rebuilt after 1974 withstood the 1997 flood with relatively minor damages. • The 1964 flood also affected water service in the city. The filtration system was overloaded and the water was muddy, although still potable. • In 1948, the water treatment plant was overloaded with silt, and citizens were advised to boil all drinking water for three weeks. Winburn Way was also a problem during this flood. A city fire truck fell through the bridge, which had been damaged in the flood. After this event, a box culvert was added to the downstream end of the Winburn Way bridge. The Surrounding Landscape of Ashland Creek The Ashland Creek watershed, which has not been subject to logging activity since 1972, consists of steep terrain and dense stands of fir and pine growing on decomposed granite soils. The instability of this type of soil is the reason for the erosion of the creek's banks which has occurred along the channel. Lithia Park is a key point in the stream corridor, and it has a long history of use as a public park. This park has been a focal point of the city and a source of civic pride. Although Ashland Creek has been heavily impacted by humans, it maintains a somewhat natural character even in the heart of downtown Ashland as it passes through Lithia Park. Below the park, Ashland Creek flows through the city's downtown, and in this vicinity is extremely developed. The stream' hydraulic capacity is restricted in many places by rock, gunite, culverts, and retaining walls. The area of the city adjacent to the creek is Ashland Creek Flood Restoration Project - Final Report 3 Otak P: \ PROJECT \ 7800 \ 7944 \ FLDREPOR \REPORT.O30 a matrix of urban streets and buildings, with fairly flat topography. The creek itself is boulder strewn and has a moderate to significant gradient. Streambanks slope down to the water from the surrounding urban streets. Many of the recommendations for the creek's restoration are aimed at reversing some of the effects of urbanization by restoring riparian vegetation and allowing for a more natural channel, both in Lithia Park and in the downtown area. The Ashland Creek Flood Restoration Project The City of Ashland suffered extensive damages because of the 1997 flood. The City determined that it was not only necessary to clean up and repair streets, businesses, and public facilities, but it was also important to examine the causes of the flood damage and seek ways to reduce flood risks in the future. The 1997 flood created an opportunity to make substantial improvements to Ashland Creek and lessen the magnitude, frequency, and impact of future flood events. The City of Ashland contracted with the Otak team to undertake hydrologic and hydraulic investigation and develop a restoration plan for Ashland Creek between the Butler band shell in Lithia Park and Hersey Street, including the design of a new crossing for Winburn Way. The team's approach to the project has been a systematic, three-pronged one, with full consideration given to the fisheries/environmental, engineering/hydraulics, and social impacts of the recommended solutions. The Otak team has completed an extensive hydrologic study of the Creek, worked to involve the public, identified problem areas in the creek, created a computerized hydraulic model, and completed design of the first phase of improvements: the Winburn Way Bridge, for which construction began in early October 1997. The team believes that there are significant opportunities to reduce flood damage along the Ashland Creek corridor in a cost-effective manner, while simultaneously enhancing fisheries habitat and providing enhanced opportunities for close human interaction with the cherished creek. The system-wide approach to this project was important to Ashland citizens, who have been active and interested in Ashland Creek and the efforts to reduce flood impacts. Through the public involvement opportunities during all phases and tasks of the project, Ashland citizens have expressed particular concern that solutions provide for protection and improvement of the riparian zone of the creek and the character of the city, as well as reduction of the risk of future flooding. Ashland Creek Flood Restoration Project - Final Report 4 Ctak P: \ PROJECT \7800 \ 7844 \ FLDREPOR \ REPORT.030 EXECUTIVE SLTYU4ARY The Ashland Creek Flood Restoration Project has been a dynamic process with continued modification over the course of several phases. These included: • Early Action Recommendations • Winburn Way Crossing Replacement • Recommendations for Further Action and Improvements Beginning with the first town hall meeting, it was evident to the consultants, city staff, and the general public that an important component of the project was the identification of early action items that would allow the city to begin to recover from the devastating effects of the flood. In particular, citizens were concerned with the repair of the lower Lithia Park entrance, a community focal point which had sustained substantial damage during the flood. The second major concern was that recommendations be developed for improvements to reduce the risk of flooding as early as the 1997-98 flood season, in case another flood event occurred. Specific recommendations for early action items were presented to the City and the park department in June, and are included in this report as Appendix Five. The culvert at the Winburn Way crossing continued to pose a serious flooding threat in the project area. Through the use of public participation meetings and input from the City, local professionals, and citizens, a decision was made to proceed with the evaluation of improving the crossing this building season. A major reason for this decision was the team's finding that improvements to the crossing would measurably reduce the overall risk of flooding within the project area. Through the public process and with input from the Otak team, the new design selected was a Con Span@ precast arch bridge with a span of 32 feet and a length of 72 feet that would replace the 141- foot-long culvert. Concurrently with the evaluation of early action improvements, the Otak Team began undertaking a methodical review of longer term needs within the project area. Citizen input, scientific data, community preferences, and staff guidance were combined and analyzed with new technology to produce sound recommendations for longer term solutions. These recommendations are incorporated within this report and include recommendations for capital improvements, flood hazard mitigation, and management procedures. Data Collection The consultant team spent the first few months of the project collecting data on the Creek and the 1997 New Year's Day Flood. All of this data has been documented and included in the team's reports. Much of the data was used in the development of the hydraulic model of the Creek. Ashland Creek Flood Restoration Project - Final Report 5 Otak P: \ PROJECT\ 7800 \ 7844 \ FLDREPOR \ REPORT.030 • Interviews were conducted with local residents with specific knowledge about the flood or the Creek in order to gather the full breadth of public knowledge about the Creek. • Engineering data on the types of existing crossings was compiled. • A new topographic survey was completed. • High-water marks were surveyed. • A stream environmental study was conducted. • A fish habitat analysis was conducted. Hydrologic Study The purpose of the hydrologic study was to estimate the magnitudes of flood events for various return periods on Ashland Creek. The hydrologic analysis of the Ashland Creek watershed made use of historic flood events from nearby watersheds with similar soil, vegetation, and topographic characteristics to Ashland Creek's, and compared five methods of calculating peak flows. As a result of the study, recommendations have been made to improve conveyance capacity of the creek channel where the hydraulic study indicated that channel deficiencies exist. Hydraulic Study and Modeling A computerized hydraulic model called HEC-RAS, developed by the Army Corps of Engineers Hydrologic Engineering Center, was prepared and calibrated using the new topographic data collected by the consultant team. This model is in common use for open channel hydraulic studies and is widely accepted for use in FEMA flood insurance studies. It is a one-dimensional steady state hydraulic computer model, and is designed to predict water levels based on cross-section geometry, channel roughness, structures, and encroachments. The model does not incorporate sedimentation, debris loading, avalanche events, or landslide potential. These factors are generally part of hydrologic, rather than hydraulic, investigation, and were incorporated into the team's hydrologic analysis of the watershed. The HEC-RAS model was used to examine various improvement scenarios for the Creek. Four conditions were run, with each condition run for the 100-year flood and for lesser flows. The "no structures" scenario was run to verify the hydraulic impact of existing structures. The existing conditions scenario was run to establish the base condition. The Winburn Way bridge scenario was run with different alignments and span widths to determine optimal sizing. This scenario also was run both with and without the flood wall in lower Lithia Park, and assumed that the cantilevered deck off Calle Guanajuato had been removed. A "multiple proposed scenarios" model was run to Ashland Creek Flood Restoration Project - Final Report 6 Otak P: \ PROJECT \ 7800 \ 7944 \ FLDREPOR \ REP0RT.O30 evaluate the hydraulic impact of other proposed projects along the creek corridor. Each project is independent of the others in this scenario, meaning that each project does not have a hydraulic impact on other projects. The reason for this is that there are limited backwater effects in the creek because of its steep gradient. The projects evaluated in the "multiple proposed scenarios" model were Calle Guanajuato improvements, Bluebird Park improvements, Water Street culvert improvements, and Hersey Street bridge improvements. Environmental Studies The ecology and geomorphology specialists on the Otak team conducted a detailed environmental assessment of the stream. The study documented stream geomorphology, fish and wildlife habitat, and areas with existing or potential problems, such as bank and slope instability. Within each reach of the creek, the team's ecology and geomorphology specialists documented existing conditions and developed recommendations for both short- and long-term improvements. This study allowed the team to develop reports and recommendations on aquatic resources, stream channel rehabilitation, and Lithia Park bridge and trail replacement. The results of the environmental assessment provide the city with a clear picture of the condition of the stream corridor currently and recommended actions or projects that will improve the overall condition of the creek. Public Involvement Process Together with City of Ashland staff, the members of the Otak team have endeavored to create one of the most extensive public involvement processes in Ashland's history, with many opportunities for citizens to participate in Ashland Creek Flood Restoration Project efforts. Since the start of the Ashland Creek project, the project team has worked with community members to get citizen input and comments and to keep the public informed of the project status. In order to reach the broadest range of citizens possible, a multifaceted approach to public involvement was taken, with efforts including a series of public focus meetings, a town hall meeting, newsletters, an interpretive display, and regular media contact. The term "focus meeting" refers to the design of these meetings so that each meeting would focus in on one aspect of the entire complex project. The citizens of Ashland have had many opportunities to become involved in the Ashland Creek restoration process, and to shape the direction of the restoration of Ashland Creek. The citizenry has made it clear that it does not want to experience again the disastrous flooding that occurred this past year, and that restoring and maintaining healthy riparian habitat, while protecting the city from flooding and maintaining the character of the community and its major park, are very important issues. The project Ashland Creek Flood Restoration Project - Final Report 7 Otak P: \ PROJECT \ 7800 \ 7844 \ FLDREPOR\REPORT.030 team's broad effort at involving the public has been successful, in that most citizens understand the issues and are aware of the proposed alternatives. Early Action Items • Lithia Park Lawn To repair flood damage, the Lithia Park lawn was regraded and reseeded based on the team's input. The regrading was designed to work with the proposed flood wall in Lithia Park. • Lithia Park Flood Wall The Lithia Park flood wall, for which construction documents have been prepared at the writing of this report, is a structural concrete block wall which is to be faced with stone. The structural portion of the wall will be 3 feet 4 inches above grade, and the stone facing will add a few additional inches of height. The wall is designed to have approximately one foot of freeboard during the 100-year flood event. The wall and the Winburn Way bridge will together work as a flood control system, and will accommodate the 100-year flood as long as a few sandbags are placed across the pedestrian path in Lithia Park. A contractor has been selected, and the wall should constructed by the end of 1997. • Winburn Way Bridge Through the community involvement process, seven alternatives for the Winburn Way crossing were evaluated. The decision was made by the City Council to use a Con Span® precast arch bridge/culvert system because this type of bridge was the most attractive for its cost, and would be an improvement to fish habitat in addition to providing flood protection. The existing crossing at Winburn Way is a combination of an 86.5' long by 21' wide by 6' high arch culvert at the inlet side and a 50' long by 13' wide by 7' high box culvert at the outlet side. The two sections meet at an angle, and in total the entire culvert is more than 141' in length. This culvert's capacity is less than 1000 cfs prior to overtopping. The proposed Con Span® bridge will be 72' in length by 32' in width by 9' in height, and has been designed, together with the Lithia Park flood wall, to convey the 100- year design flood event. The creek will run over its natural bottom, a significant improvement for fish habitat over the existing culvert. The HEC-RAS hydraulic model was used to run various alignment scenarios in order to determine the optimal design. During a community charrette meeting in August, the physical appearance of the new crossing was determined. Ashland Creek Flood Restoration Project - Final Report 8 Otak P: \ PROJECT \ 7800 \ 7 844 \ FLDREPOR \ REPORT.030 The team obtained state and federal permits for the bridge, and Otak completed construction drawings and ran the bidding process in September 1997. CDA Consulting Group, a member of the team, felt so strongly about the project that the firm provided its grant writing expertise to the city free of charge. CDA was able to procure $150,000 for the project from the FEMA Hazard Mitigation Grant Program, and put forth a three month effort to ensure that Ashland would receive the grant funds. The bridge is under construction at the writing of this report, and will be in place for the 1997-98 flood season. Ashland Creek Flood Restoration Project - Final Report 9 Otak P: \ PROJECT \ 7800 \7844 \ FLDREPOR\ REPORT.030 RECOMMENDATIONS This portion of the report identifies recommendations relating to the Ashland Creek Flood Restoration Project. These recommendations are grouped into five categories including: 1: Flood Control 2: Flood Management Plan 3: Flood Design Standard Improvements 4: Habitat and the Environment 5: Aesthetic Considerations and Community Character For the purpose of these recommendations, "stream channel" is defined as the area between the top of banks; "stream corridor" is generally defined as the area within the floodplain; and "significant impact" is defined as impacts considered significant by City staff and the professionals working on the project. 1: Flood Control We recommend that the City should endeavor to provide measures for flood control along Ashland Creek to reduce the risk of flood damage to public and private properties. The following recommendations will improve flood conveyance and reduce flood risks. • Recommendation 1-1: Construct a flood wall in Lithia Park to provide greater flood protection. The flood wall, which is under construction as this report is being written, is a structural concrete block wall which is to be faced with stone. The structural portion of the wall will be 3 feet 4 inches above grade, and the stone facing will add a few additional inches of height. The wall is designed to have approximately one foot of freeboard during the 100-year flood event. The wall and the Winburn Way bridge will together work as a flood control system, and will accommodate the 100-year flood as long as a few sandbags are placed across the pedestrian path in Lithia Park, in accordance with the Flood Management Plan. Without the flood wall, the bridge alone would provide about the 25-year level of flood protection. • Recommendation 1-2: The City should seek to maintain a specific channel capacity for Ashland Creek. The typical existing channel capacity of Ashland Creek is about 1,500 cfs, and the recommendation is that this capacity be maintained in the future. The hydraulic capacity of the creek channel is the amount of water it can convey at bank full depth. Outside the banks of the creek, there is still floodplain which can convey Ashland Creek Flood Restoration Project - Final Report 10 C!tak P: \ PROJECT\ 7800 \7844 \ FLDREPOR \ REPORT.030 greater flood flows. Maintaining a specific channel capacity will ensure that there are no encroachments in the channel, which will prevent the creek from passing the maximum amount of water. • Recommendation 1-3: Existing gunite should be removed, replaced, or rein forced. Several sections of Ashland Creek's banks were, at some time in the past, coated with gunite as an erosion protection measure. Particularly in the Calle Guanajuato, the gunite is now showing obvious signs of distress and partial failure, probably in response to the New Year's Day flood and the passage of time. At several locations inspected at random, voids were observed behind the concrete shell where water has penetrated and washed out fine soil particles. The gunite in these areas needs to be removed or repaired so that rapid bank collapse does not occur during future high water periods. The Otak team urges that careful consideration be given to restoring bank protection in the gunited areas with other, more environmentally friendly solutions such as riparian benches or biotechnical approaches to streambank protection. Some of these alternative approaches may be more acceptable in areas that do not have strong economic justification for conventional structural flood protection systems. The urgent need to restore or replace the failing gunite areas creates an opportunity to consider more environmentally friendly options for the Calle area, especially in light of the findings of the hydraulic study, which shows the need for a parapet-style flood wall through the Calle area to provide 100-year flood protection to existing businesses. Under the sponsorship of the Ashland Parks and Recreation Department, a "visioning" process for the future of the Calle Guanajuato will start soon. • Recommendation 1-4: The cantilevered deck should be removed from the Calle. The cantilevered deck is structurally unsafe, and is a major impediment to flood flow. The deck catches floating debris during flood events and, during the 1997 flood, caused debris blockages that exacerbated the flood damage. Note: Removal of this structure was accomplished as part of the demolition task for the Winburn Way culvert replacement project. • Recommendation 1-5. The City should consider adopting a stream setback ordinance. The Physical and Environmental Constraints chapter (adopted in 1994) of the Ashland Land Use Ordinance requires that development in the floodway, in creek corridors, and in other sensitive areas undergo environmental review. However, development within the stream corridor is still permitted, provided that City staff find that the criteria for review are met. A stream setback ordinance would Ashland Creek Flood Restoration Project - Final Report 11 ocak P: \ PROJECT\ 7800 \ 7844 \ FLDREPOR \ REPORT.030 establish a no-build line, and would provide both habitat and flood protection. A stream setback ordinance could be complementary to the Physical and Environmental Constraints chapter. • Recommendation 1-6: The City should consider designating existing buildings in the floodway as "nonconforming structures or uses". This issue will be a political one, and the City will need to consider the variety of positions held by property owners and citizens. The main question in determining how much or little regulation to place on structures in the floodway is the degree of risk they pose for the greater community. The City should examine this question, and based on the consensus within the community, make changes to current regulations or allow them to remain the same. The positions outlined below are examples, and they vary in their degree of regulation. The City will need to balance the greater public good with the past precedent of building within the floodway and the rights of the property owner. If the City chooses to designate buildings in the floodway as nonconforming, there are degrees of regulation which can be imposed. Currently, nonconforming structures or uses are allowed to be expanded or remodeled through the conditional use permit procedure. The City may wish to designate structures in the floodway as nonconforming and continue to allow their enlargement or reconstruction through this procedure. The City could also determine that structures in the floodway are hazardous to the community, and could add a category under 18.68.090(A) of the Land Use Ordinance, to state that structures within the floodway may not be enlarged, extended, reconstructed, or structurally altered without meeting the standards contained in Chapter 18.62 on Physical and Environmental Constraints of the Ashland Land Use Ordinance. As another option, the City could determine that structures in the floodway are such a hazard to the greater community that reconstruction of buildings destroyed or severely damaged by flood, fire, or other hazard will not be permitted. 2: Flood Management Plan To reduce the risk of property damage during flood events, the City should prepare a flood management plan that will establish policy for managing the Ashland Creek floodway. The City should also consider refinements to the emergency response plan. • Recommendation 2-1: An annual review of flood hazard conditions should be conducted Conducting a field review of flood hazard conditions each autumn will help the City to locate potential problem areas, and ensure that risks are minimized to the extent practicable before the flood season begins each year. Ashland Creek Flood Restoration Project - Final Report 12 Ofak P: \ PROJECT\ 7800 \ 7844 \ FLDREPOR \ REPORT.030 • Recommendation 2-2: The City should on an annual basis remove woody debris within the floodplain that is not providing riparian habitat. Woody debris floats, and can potentially create debris jams at channel constrictions or creek crossings during high flow periods. Debris which is outside of the active stream channel does not provide fish habitat, and therefore creates a hazard without providing benefit. This debris should be removed at least annually before the start of the flood season. • Recommendation 2-3. The City should conduct a yearly assessment of the physical condition of creekside trees that could potentially topple into the creek during high water events. Trees that are diseased or that already have a portion of the root mass exposed by erosion should be removed and replaced with healthy stock. These trees are more likely to topple during flood events. Removing potentially hazardous trees before each flood season begins will reduce floating debris during floods. Appropriate native species should be selected for planting along the creek corridor and should be encouraged as a way of providing shade for the aquatic environment. However, locations that are prone to erosion should not be planted. • Recommendation 2-4: The City should specify that park furniture be either removable or able to withstand flood conditions. During the 1997 flood, park furniture (picnic tables, benches, and footbridges) were washed away by the flood waters and contributed to the debris flow in the creek. Specifying that the furniture be removable or able to withstand floods will minimize this risk, and will also ensure that the furniture lasts for a longer period of time, thereby keeping replacement costs lower. • Recommendation 2-5. The City should designate a staff member as the flood management reviewer to make decisions about flood management activities. The flood management reviewer would be granted the authority to determine what flood management activities need to occur each year, including removal of trees and debris from the floodway. A staff person in the City's Engineering Department, the Emergency Coordinator, or an outside consultant are potential alternatives to fill this role. Ashland Creek Flood Restoration Project - Final Report 13 Ctak P:\PROJECT\7800\7844\FLDREPOR\REPORT.O30 • Recommendation 2-6. The City should consider the following recommendations to refine the existing Emergency Response Plan. • Recommendation 2-6a: The City should designate a Flood Emergency Response Coordinator who will make all decisions relating to the flood emergency. • Recommendation 2-6b: The Emergency Response Coordinator should pre-assign foreseeable Emergency Response tasks to specific individuals. • Recommendation 2-6c: The Emergency Response Coordinator should plan for emergency communication, particularly anticipating that phone lines or cellular phones will not be functional. • Recommendation 2-6d: The Emergency Response Coordinator should have equipment contacts ready for emergencies. This includes an inventory list of various types of readily available public and private equipment which could be used in the event of an emergency. • Recommendation 2-6e: The City should maintain a sandbag stockpile, but not store sandbags in a filled condition. The City could purchase a sandbag filling machine to speed response time during floods. • Recommendation 2-6f.- During flood conditions, the left bank near the rose garden should be sandbagged (Stations 109+00 and 110+00). • Recommendation 2-6g: During flood conditions, the new Lithia Park flood wall should be sandbagged at the pedestrian walkway near the duck pond. • Recommendation 2-6h: Park furniture should be removed from the floodway whenever the likelihood of a flood is high. • Recommendation 2-61: A procedure should be established for contacting at-risk properties during expected high water periods. • Recommendation 2-6j: The Emergency Response Coordinator should conduct annual training and drills for City staff and key volunteers (i.e., high school service clubs, Boy Scouts, etc.). 3: Flood Design Standard and Improvements When improvements are proposed to Ashland Creek, the City should ensure that reasonable efforts are made to design them to convey without any backwater effect or withstand the 100-year flood. Some practical exceptions may be appropriate where improvements are made to existing structures. Ashland Creek Flood Restoration Project - Final Report 14 Otak P: \ PROJECT\ 7800 \ 7844 \ FLDREPOR \ REPORT.030 • Recommendation 3-1: All flood improvements should be designed to pass 3100 cfs. After conducting hydrologic and hydraulic analysis, Otak has determined that 3100 cfs is the peak flow of the 100-year flood. This figure was arrived at through the use of the Index Flood method, which uses real data from nearby watersheds with similar hydrologic conditions to the Ashland Creek watershed. The report on the hydrologic investigation of the creek is included as Appendix Two. By adopting 3100 cfs as the standard for 100-year flood protection, the City will make design of future projects to a single standard more efficient. • Recommendation 3-2: The Water Street bridge should be replaced The Water Street twin culvert crossing currently has a low conveyance capacity, and can cause flood impacts by flood water overflowing Water Street up and downstream of the culverts. Sufficient economic justification exists to support its replacement with an appropriately sized structure (see Recommendation 3-1) as soon as possible. • Recommendation 3-3: Pedestrian bridges should be designed to pass the 100-year flood event, or otherwise be designed to minimize flood hazards. During the 1997 flood, nine bridges in Lithia Park were destroyed. During the 1974 flood, all the pedestrian bridges in existence at that time were destroyed. Many of the destroyed pedestrian bridges were constructed of wood, which floats. The debris from the destruction of bridges can become a hazard downstream, where it can become lodged against obstructions with unforeseen consequences. After floods, destroyed bridges need to be replaced, which can be expensive and inconvenient. Ideally, pedestrian bridges should be built to pass 3100 cfs, the same standard recommended for other reconstruction projects along the stream corridor so that a uniform flood protection system is in place. Those bridges that cannot be designed to pass the 100-year flood event should be designed to accommodate the flood waters in alternative ways so that they do not become a downstream hazard and can survive the flood. One alternative option is for replacement pedestrian bridges to be constructed of non-floatable materials such as concrete or steel in order to reduce the potential for the bridges to become flood debris. If the replacement bridges should be destroyed during a future flood event, the debris will sink to the creek bed nearby and not be transported significant distances downstream. Another option is to design the bridges for easy removal during future high water events. 4: Habitat and the Environment The City should endeavor to maintain, encourage, and improve aquatic, riparian, and wildlife habitat as part of any project for altering or improving Ashland Creek and its bridges, crossings, utility installations, recreational facilities, and any other Ashland Creek Flood Restoration Project - Final Report 15 Otak P: \ PROJECT \ 7800 \ 7844 \ FLDREPOR \ REPORT.030 construction that may impact the stream. Habitat enhancement projects that are independent of public works or parks capital improvement projects should also be encouraged. • Recommendation 4-1: The City should continue to endorse and to follow the Valdez principles. The Valdez principles make a statement about the City's commitment to environmental responsibility. Valdez Principles By endorsing these Principles, we publicly affirm our belief that the City of Ashland, Oregon, has a direct responsibility for the environment. We believe that we must conduct the public's business as responsible stewards of the environment and seek goals only in a manner that leaves the Earth healthy and safe. We believe that the City must not compromise the ability of future generations to sustain their needs. We recognize this to be a long-term commitment to update our practices continually in light of advances in technology and new understandings in health and environmental science. We intend to make consistent, measurable progress toward the ideal that these principles describe, and to apply them wherever we operate, in a manner consistent with our other obligations under law. 1. Protection of the Biosphere. We will minimize and strive to eliminate the release of any pollutant that may cause environmental damage to air, water, or earth or its inhabitants. We will safeguard habitats in creeks, ponds, wetlands, natural areas, and will minimize contributing to global warming, depletion of the ozone layer, acid rain, or smog. 2. Sustainable Use of Natural Resources. We will make sustainable use of renewable natural resources, such as water, soils and forests. We will conserve nonrenewable natural resources through efficient use and careful planning. We will protect wildlife habitat, open spaces, and wilderness, while preserving biodiversity. 3. Reduction and Disposal of Waste. We will minimize the creation of waste, and wherever possible, recycle materials. We will dispose of all wastes through safe and responsible methods. 4. Wise Use of Energy We will make every effort to use environmentally safe and sustainable energy sources to meet our needs. We will invest in and promote energy efficiency and conservation in our operations and that of our citizens. Ashland Creek Flood Restoration Project - Final Report 16 Otak P: \ PROJECT \ 7800 \ 7844 \ FLDREPOR\ REPORT.030 5. Risk Reduction. We will minimize the environmental, health and safety risks to our employees and the communities in which we operate by employing safe technologies and operating procedures and by being constantly prepared for emergencies. 6. Safe Products and Services. We will provide services that minimize adverse environmental impacts and that are safe for consumers. We will inform consumers of the environmental impacts of our services. 7. Damage Compensation We will take responsibility for any harm we cause to the environment by making every effort to fully restore the environment and to compensate those persons who are adversely affected. 8. Disclosure We will disclose to our employees and to the public incidents relating to our operations that cause environmental harm or pose health or safety hazards. We will disclose potential environmental, health, or safety hazards posed by our operations, and we will not take any action against employees who report any condition that creates a danger to the environment or poses health and safety hazards. 9. Environmental Directors and Managers At lease one member of management will be a person qualified to represent environmental interests, and will commit management resources to implement these Principles. 10. Annual Assessment We will conduct and make public an annual self-evaluation of our progress in implementing these Principles and in complying with all applicable laws and regulations. Endorsed by the Ashland City Council - May 15, 1990. • Recommendation 4-2: Replace or remove pedestrian bridges in Lithia Park. One of the team's tasks under a separate phase of this project was to conduct a study of the bridges in Lithia Park. Within the project area defined for this phase of the project (Hersey Street to Butler band shell), the study found two locations in the park where bridge were destroyed during the 1997 flood. The other two bridges within the project area survived the flood. The Environmental Report contained in Appendix Four includes specific discussion of each of these bridges. The report recommends that one of the missing bridges not be replaced, and that the other Ashland Creek Flood Restoration Project - Final Report 17 Otak P: \ PROJECT\ 7800\7844\ FLDREPOR\REPORT.030 missing bridge be replaced with a longer span and broader arch. The remaining two bridges were determined to be acceptable in their locations, and it is recommended that the City conduct as-needed repair of flood damage and minor erosion. • Recommendation 4-3: New pedestrian bridge locations and layouts should be approved by a qualified environmental consulting firm. New designs for bridges should be reviewed by a qualified environmental consulting firm to ensure that the bridges are optimally sited to reduce bank undercutting and erosion, and maximize potential habitat. • Recommendation 4-4: Erosion control measures should be taken for future improvements to the Calle Guanajuato and to other areas adjacent to the creek. Erosion control measures will prevent destruction through siltation of potential fish spawning habitat. • Recommendation 4-5. The City and Park Commission should adopt guidelines for the types of stream bank protection measures allowed along Ashland Creek. The adopted guidelines should encourage the use of native materials where possible and designs that result in natural appearing and aesthetically pleasing streambanks. The guidelines should not preclude the use of concrete, rip rap, or other standard engineering materials and designs where those are warranted by site specific conditions. • Recommendation 4-6: The City should establish a review procedure for proposed planting or removal of woody vegetation in the stream corridor. This review should consider, at minimum, ecological, flood reduction and protection, recreational, and silvicultural factors in a holistic manner. • Recommendation 4-7: Any projects proposed within the stream channel should include design elements that will allow upstream and downstream passage by juvenile and adult fish, particularly steelhead and salmon. Designs that do not allow fish passage will further limit existing fish travel, and will preclude future development of programs to increase fish population in the creek. Ashland Creek Flood Restoration Project - Final Report 18 Otak P: \ PROJECT\ 7 800 \ 7844 \ FLDREPOR \ REPORT.030 • Recommendation 4-8: The City should establish a procedure to evaluate proposed projects within the stream channel or stream corridor for potential impacts, including short-term, long-term, and cumulative, to fish and wildlife habitat and stream hydrology and hydraulics. The procedure should consider project alternatives in order to select the alternative that avoids or minimizes, to the greatest extent practicable, significant adverse impacts. • Recommendation 4-9: The City should encourage public use of the stream corridor for appropriate recreational activities. "Appropriate" in this case means those activities that do not harm the ecological or structural integrity of the urban stream corridor. Access to the stream channel should be encouraged at locations that result in no harm to stream ecology or structure, and be discouraged at locations that will result in harm to the stream habitat values. • Recommendation 4-10. The City should meet with Oregon Department of Fish and Wildlife (ODFW) to determine ODFW fish production goals for Ashland Creek. After establishing goals for the creek, cooperative programs with local citizens and nearby colleges and universities can be established to meet these goals through habitat improvement or enhancement. • Recommendation 4-11: The City should review the Environmental Report's (Appendix Four) recommended short-term improvements and develop a plan for their implementation. The Environmental Report contains detailed recommendations for short-term improvements for each reach of the stream. • Recommendation 4-12: The City should review the Environmental Report's (Appendix Four) recommended long-term improvements and determine which of these to adopt. A long range plan for implementing the improvements should be developed The Environmental Report contains detailed recommendations for long-term improvements for each reach of the stream. Ashland Creek Flood Restoration Project - Final Report 19 Otak P: \PROJECT\ 7800 \ 7844 \ FLDREPOR\ REPORT.030 • Recommendation 4-13: The duck pond outflow should be connected to the city sanitary sewer system. The lower Lithia Park duck pond has a large resident duck population that is fed year-round by local residents and tourists alike. The ducks are clearly popular, but their large numbers generate a substantial quantity of droppings that accumulate in the bottom of the pond. Parks Department staff typically drain and clean the pond three or four times a year. When the pond is drained, the highly polluted water is released directly into Ashland Creek, where it stimulates algae growth and causes a spike in creek temperature. The creek is already quite warm in the summertime, at near-lethal levels in terms of fish survival. Overflow from the pond drains directly into Ashland Creek, so that the polluted water continuously runs directly into the creek. The City should explore the possibility of re-routing the duck pond drain and overflow outlet into the City sanitary sewer system, where the polluted water can be treated like ordinary wastewater. 5: Aesthetic Considerations and Community Character To enrich the character of the community, the City should take aesthetic and architectural considerations into account as part of any project for altering or improving Ashland Creek and its bridges, crossings, utility installations, and recreational facilities. • Recommendation 5-1: Community involvement should guide aesthetic decisions for future improvements. The community of Ashland has a rich heritage, and citizens have expressed a strong desire to increase the City's character and livability as future development occurs. Aesthetic design has always been an important element in the growth of Ashland and will continue to be a focal point for public participation. Citizens should continue to be encouraged to share viewpoints and ideas on how to enhance livability through aesthetic design and the consideration of function. Citizen input into the aesthetic decisions guided the design and appearance of the Winburn Way bridge. This process can serve as a model for future improvement projects. Ashland Creek Flood Restoration Project - Final Report 20 Otak P: \PROJECT\ 7800 \7844 \FLDREPOR\ REPORT.030 APPENDIX ONE to Ashland Creek Flood Restoration Project Final Report November 3, 1997 Ashland Creek Public Involvement Process October 31, 1997 Submitted to: City of Ashland Ashland, Oregon Submitted by: CDA Consulting Group P.O. Box 3311 Portland, OR 97208-3311 (503) 227-3487 ASHLAND CREEK FLOOD RESTORATION PROJECT THE PUBLIC INVOLVEMENT PROCESS October 10, 1997 Prepared by: CDA Consulting Group P.O. Box 3311 Portland, OR 97208-3311 (503) 227-3487 THE PUBLIC INVOLVEMENT PROCESS Ashland citizens have worked to create a vibrant community. Because the flood affected every member of the community, there was substantial interest on the part of the public in ensuring that important community values were taken into consideration throughout the process of the Ashland Creek Flood Restoration Project, as well as in minimizing future damage. CDA Consulting Group and the other members of the Otak team have endeavored to create one of the most extensive public involvement processes in Ashland's history, with numerous opportunities for citizens to participate in Ashland Creek Flood Restoration Project efforts. The public involvement component of the project was aimed at reaching the broadest range of citizens possible. The team created a periodic project newsletter, hosted a series of public meetings, interviewed citizens, scheduled time for one-on-one discussions with consultants, designed and installed an interpretive display in Lithia Park, and maintained a project mailing address and electronic mail address for citizen comments. OVERVIEW OF THE PUBLIC INVOLVEMENT PROCESS Interviews To begin the process and to gain valuable insight, in early April more than 20 interviews were conducted by the project team with local citizens who had specific interest in or knowledge contributing to the Flood Restoration Project. These citizens included representatives of the Lithia Arts Guild, the city, and the Ashland Watershed Partnership; members of Ashland Parks and Recreation Department staff; Plaza business owners; and concerned citizens. Presentations CDA and Fishman Environmental Services (FES), members of the Otak team, gave a presentation on the project to the Ashland Watershed Partnership on April 22, 1997. Team members also attended the Chamber of Commerce forum on civic issues including flood restoration efforts on April 23, 1997. In addition, at every public meeting, the team gave a presentation of new progress on the project. Team members have also attended Park and Recreation Commission meetings and City Council meetings. Town Hall Meeting A town hall meeting was held on May 7, 1997 at the City Council Chambers. This meeting was open to the entire citizenry, and was advertised in the Daily Tidings. The meeting was used to introduce the project scope to the public and to gain preferences for evaluating 71 THE PUBLIC INVOLVEMENT PROCESS PAGE 1 CDA CONSULTING GROUP recommendations. As a result of this meeting the Otak Team proposed a change in the public involvement process to be more responsive to citizen interests. The use of Focus Meeting was identified as a way in which citizens could evaluate issues related to certain tasks or elements of the project. Focus Meetings The term "focus meeting" refers to the design of these meetings so that each meeting would focus in on one aspect of the entire complex project. Focus meetings were designed so that numerous opportunities for citizen input and dialogue would be provided, while ensuring that sufficient time was devoted to discussion of each element of the project. This series of meetings was scheduled for every other Thursday, beginning in June. The schedule was developed with input from city staff, and was specifically chosen to make the meeting dates easy to remember. June 12 Winburn Way Crossing Alternatives June 26 Flood Management Plan July 10 Stream Corridor Habitat July 24 Hydraulic Model/ Identify and Prioritize Problems and Alternatives August 7 Architectural and Design Elements of the Winburn Way Bridge August 18 Modeling Results In order to be responsive to community concerns, the meeting topics were flexible and subject to change. The team attempted to modify the agenda or approach of the meetings to meet citizen concerns. For example, the August 7 meeting topic was changed from hydraulic modeling results to design elements in order to respond to citizen interest in the appearance and aesthetics of the proposed Winburn Way bridge. The Community Center and Pioneer Hall were chosen as the primary locations of the focus meetings because both places seat up to 75 people, yet maintain a comfortable setting. The seating at the meetings was arranged to encourage discussion among citizens as well as the consultants. At the beginning of each meeting, the team made a presentation summarizing accomplishments since the previous meeting and identifying any action items initiated based on the previous meeting. Then, the objectives of the evening's meeting were outlined by the presenters, and illustrated by presentation boards. In addition, agendas and informational handouts were prepared for each meeting. More than half of the time allotted for each meeting was reserved for citizen discussion. This format was designed to allow the consultants an opportunity to present new concepts and information to the public, while ensuring enough time for public commentary and THE PUBLIC INVOLVEMENT PROCESS PAGE 2 CDA CONSULTING GROUP discussion of the project. An opportunity to comment was provided to anyone who wished to speak, with the facilitator, Clay Moorhead, progressing through the audience several times on each topic to ensure that everyone had an opportunity to comment. During each meeting, an announcement was made that the consultants would be available afterwards to speak personally with anyone on any aspect of the project. Notices of meetings also advertised this. The consultants specifically arranged their time in this way so that another type of interaction would be available to Ashland citizens. Copies of the meeting agendas for the July 24th and August 7th focus meetings appear at the end of this appendix. Other Communication A project mailing address at City Hall was established to make it easier to send comments to the city or the consultants. A central City Hall contact person and phone number was designated to encourage citizens to obtain information directly from City Hall. Phone numbers for each of the consultants were listed so that direct contact could be made by concerned citizens. A project E-mail address, cdagroup@transport.com, was publicized to provide an alternate means for citizens to send information, concerns, and questions to the consultants. An informational display describing restoration efforts was designed and installed in Lithia Park. The display included a focus meeting schedule and the project mailing address for comments. Notices The notice mailing list grew with each step of the process, with a final total of more than 200 mailed notices sent out to members of the public and interested parties. These notices were sent out at regular intervals to encourage involvement. Each of the notices included a meeting schedule, proposed topics and objectives, and phone numbers and addresses for more information or comments. The notices also advertised that the consultants were available one half hour prior to each meeting for individual discussion or to review any issue raised in previous meetings. Notice was mailed to: The City Council, Ashland Planning Commission, and Park Commission Individual members of the Ashland Watershed Partnership The Lithia Arts Guild Property owners along the creek Plaza Merchants The Chamber of Commerce Cable access television KMVU Fox 26 THE PUBLIC INVOLVEMENT PROCESS PAGE 3 CDA CONSULTING GROUP KDRV Channel 12 Southern Oregon Public Television KOBI Jefferson Public Radio The Ashland Daily Tidings Medford Mail Tribune The Ashland Garden Club The League of Women Voters The Friends of Ashland The Ashland Historic Commission The Rotary Club The Ashland Public Library Other interested persons signed up on the project mailing list Notice was placed in the Meeting and Government sections of both local newspapers, and display advertisements were also placed in both papers. Also, the consultants encouraged coverage in the local newspapers prior to each Focus Meeting by contacting the newspaper and providing information on the meeting topic. For example, the illustrations showing alternatives for the Winburn Way crossing from the Lithia Park display were digitally transmitted to the Ashland Daily Tidings, and were printed in the paper with an article describing the alternatives. Additional notice was provided through a series of newsletters that were prepared by the project team. The newsletters were mailed to all mailing list addresses and were also handed out at the focus meetings. Extra copies were placed in a bin in the interpretive display in Lithia Park. An example of the newsletter is also reproduced at the end of this appendix. SUMMARY OF THE FOCUS MEETINGS June 12: Winburn Way Crossing Alternatives At the first focus meeting, the team presented several alternative possibilities for improvement to the Winburn Way crossing. Others were suggested through public discussion. In total, seven alternatives were discussed and evaluated. The team prepared a matrix of all seven alternatives, including the "do nothing" alternative, and prepared perspective drawings of four of the alternatives. A copy of the matrix appears at the back of this appendix. Those attending the meeting favored the Con Span@ prefabricated bridge structure, because this type of bridge has most of the advantages of a site-designed bridge, particularly in the area of appearance, but costs significantly less. Discussion also occurred relating to the life span of different alternatives. The channel alignment of the creek at this location posed a design problem that would require special consideration. Questions arose regarding the budget to making improvements to the THE PUBLIC INVOLVEMENT PROCESS PAGE 4 CDA CONSULTLNG GROUP crossing. The consultants discussed rough cost estimates for alternatives. The timelines for environmental and other permits may impact the ability to construct any alternative this building season. Water quality concerns relating to the various designs were also discussed. Several comments were expressed that the creek is not "natural" from the reservoir through town, and that any configuration to change the capacity of the existing culvert may have affects in other locations. Truck access to the Calle was discussed. Concern was expressed that trucks should continue to be able to service the merchants in the plaza though access along the Calle. Parking issues were discussed. Desires were expressed to retain parking near the existing bathrooms if possible. Comments were received that parking is often in short supply. Participants at the meeting discussed whether it would be appropriate to pursue development of a new crossing yet this year. Comments were heard on both sides of this issue. A preference was expressed that parking areas should be reconstructed if possible. Parking could be designed to be located on the new bridge as one alternative. Parking areas could be built on "pavers" that allow a sod appearance to further enhance the area. The public restrooms were an important concern to those in attendance. The restrooms are the only facilities available within the Park/Plaza area that can be used by the general public. Without public restrooms the Plaza merchants will be burdened with continual requests to use private facilities. Comments were also received that support the need for a better recycling area that can be made cleaner and with more capacity. There was a concern expressed that the existing Plaza area is currently in the floodplain. Future flooding would continue to flood these buildings unless changes are made to the Winburn Way crossing. June 26: Flood Management Plan The purpose of this meeting was to discuss the elements of a flood management plan and how this might help the City reduce flood risk. Additionally, at the beginning of each meeting, a summary of issues presented at the previous Focus Meeting was presented. The meeting began with a presentation of alternative designs for the Winburn Way crossing. A matrix was distributed to the audience that provided generalized comparisons of the alternatives. Citizens attending the meeting identified a strong preference for a more formal flood management plan than the one the City currently has in place. Once adopted, the new flood management plan would guide the general management and maintenance of the flood hazard area. The plan could include provisions for an emergency response program that would be set in motion in the event of an actual flood. THE PUBLIC INVOLVEMENT PROCESS PAGE 5 CDA CoNSULTING GRouP Debris was discussed as a significant contributor to flood risks. Most of the bridges that gave way in Lithia Park broke up and went down stream. Debris material deposited into "jams" which directed the flood flow into the banks, resulting in great loss of bank material in certain locations. The Calle cantilevered deck and park picnic tables also contributed to flood debris problems. A tremendous amount of sediment accumulated in the channel. The swimming reservoir in Lithia Park was completely filled with sand. The citizen participants at the meeting evaluated whether a Flood Management Plan would create benefits if future flooding occurs. Discussion also occurred relating to proposed wall in the park as a flood management project. Significant discussion occurred relating to the benefits of a flood management plan. The plan should minimize future flood impact. Flood management would reduce flood damage expenses. A plan would establish expectations for the management of the floodplain. The consultants facilitated a discussion to identify problems and issues were evaluated by stream reach. The participants provided significant information relating to the impacts and problems that occurred during and as a result of the flood. July 10: Stream Corridor Habitat This meeting was led by Fishman Environmental Services. Discussion at the meeting focused on existing stream conditions in the project area and measures for possible improvements to habitat. Topics discussed included habitat issues, existing data, project tasks, community visions and goals for stream corridor habitat, channel, bank and slope rehabilitation concepts, and other topics identified by meeting participants. Paul Fishman indicated that they were collecting detailed information on what they see as they walk the entire length of the creek. The goal is to characterize the stream and to solve problems. A number of problem areas were identified. Fish habitat in the creek was discussed. Pools are infrequent and most were filled with sand after the flood. The consultants indicated that they were communicating with the Park Commission and staff regarding the removal of certain debris in the floodway. The primary focus for flood related habitat issues is for fish although the consultants took note of birds as well. Numerous other barriers were noted relating to fish passage. The consultants identified that they would record data on maps that can be evaluated in future meetings. Participants also requested an update of the hydraulic modeling efforts. Input is still being entered at this time, and the model will not produce final results until a later date. THE PUBLIC INVOLVEMENT PROCESS PAGE 6 CDA CONSULTING GROUP Discussion occurred regarding developed improvements to the stream. Many commented that the stream is "urban". The value of habitat was also discussed in context of the cost of improvement. July 24: Hydraulic Model/ Identify and Prioritize Problems and Alternatives During this meeting, the hydraulic model was described and discussed in technical detail. Engineers from Otak used charts and tables to illustrate the extent of the data required to create the model. Larry Magura indicated that the model would identify the 100 year flood design. The model can be used to evaluate changes to the Winburn Way crossing. Discussion about the Winburn Way bridge design came up. Participants requested that a special meeting be held to evaluate the aesthetic and architectural features of the bridge. Agreement was reached that a special meeting can be scheduled. Larry Magura identified that recommendations will be presented based upon the modeling results. A concern was presented regarding the ability of the model to calculate debris loading. The Otak consultants identified that the model is the state of the art hydraulic model and will create a detailed result. August 7: Architectural and Design Elements of the Winburn Way Bridge This was a charrette-style meeting, where participants broke into two groups to come up with ideas for the appearance of the bridge. Brian McCarthy assisted in the development and presentation. Each of the two groups reported back to the whole audience relating to their issues and preferences. The outcome of the meeting was a plan for the bridge that retained the architectural appearance of the Memorial Bridge in Lithia Park. A simple appearance was preferred with ornamentation for railing. Lights were identified as an important feature. Costs of lighting was also discussed. Preference was identified for a concrete structure that was tinted to an "Ashland buff' color. This color would match other concrete features in the City. The bridge should be as high as possible without affecting the access to the Calle for delivery trucks. The alignment of the bridge was also discussed. Because the bridge location is impacted by the curve of the creek and road alignment of Winburn Way, the bridge alignment took careful analysis to keep the width to a minimum. The bridge is proposed to be 72 feet long. August 18: Modeling Results Otak presented the results of the hydraulic model to show the projected impact of the 100- year storm event under two scenarios: one with existing conditions in the stream corridor and the second with specific flood reduction improvements, such as the replacement of the THE PUBLIC INVOLVEMENT PROCESS PAGE 7 CDA CONSULTING GROUP Winburn Way culvert and improvements to Calle Guanajuato. The most notable improvement in flood reduction occurred with the replacement of the 141-foot long culvert at Winburn Way. Discussion included emphasis that, while the HEC-RAS model is a state- of-the-art one-dimensional computer program, the results it generates should only be used as a guide to decision making. In the long run, it is still important to have qualified professional engineers and hydrologists interpret the model results and draw conclusions and recommendations based on their qualifications and experience. One surprising result from the modeling work that was discussed at some length was the fact that the model showed that there is very little impact downstream from making channel capacity improvements upstream because the creek hydraulic gradient is so steep. THE PUBLIC INVOLVEMENT PROCESS PAGE 8 CDA CONSULTING GROUP ASHLAND CREEK RESTORATION PROJECT Ashland Pioneer Hall July 24, 1997 FOCUS MEETING AGENDA TOPIC: Development of Computer Hydraulic Model for Ashland Creek The consultants will hold special informational meetings for those people who would like to "catch up" with some of the issues that have occurred to date. Informational meetings will be held one half hour prior to the beginning of each Focus Meeting (at 6:30 p.m.). 7:00 p.m_ Focus Meeting Begins 1. Introduction 2. Follow-up from last meeting (July 10, 1997) Stream Corridor Habitat and Related Topics 3. Project Status Report (ieotechnical Investigation (Squire Associates) Field work by hydraulic modeling team (Otak) Field work by environmental team (Fishman) New phase of work to start soon -tipper Lithia Park Reconnaissance Preliminary schedule for Winbum Way bridge replacement 4. Overview of purpose of hydraulic modeling work: to test impact of proposed improvements to Ashland Creek channel. 5. Modeling process flow chart 6. Status of model development 7. Wrap up: Question and Answer Session 3. Adjourn Comments: If you have comments that you would like to express in writing, please use this agenda and write your comments on the front or back. You may leave your written comments with any of the consultants or City staff. Thank you for participating. ASHLAND CREEK RESTORATION PROJECT SPECIAL PUBLIC MEETING Hunter Park Senior Program Building TOPIC: Winburn Way Bridge Architectural Features and Bridge Design AGENDA August 7, 1997 7:00 p.m Meeting Begins 1. Introduction of meeting topic (Clay Moorhead) 2. Winburn Way Crossing Bridge Design (Larry Magura) 3. Presentation relating to aesthetic treatments and designs (Brian McCarthy) 4. Break Out Session. The audience will break out into small groups to discuss aesthetic (appearance) related opportunities and designs for the Winbum Way Crossing. MATERIALS TO BE PROVIDED 5. Group Reports. Each group will be asked to give a brief report on the important issues discussed by the group in the Break Out Session 6. Open Discussion, Wrap Up, and Question and Answer Session 7. Adjourn at 9:00 p.m. Comments: If you have comments that you would like to express in writing, please use this agenda and write your comments on the front or back. You may leave your written comments with any of the consultants or City staff. Thank you for participating. A- Periodic lVewsletter for Ashland Creek the Ashland Creek Restoration Update Restoration Volume III August 21,1997 ProT 11111111111M I I I J. ~,~,•,r, WINBliRN WAY BRIDGE SCHEIMA7IC DESIGN ASHLAND. OREGON W1nbL11"n Way Crossing Bridge Replacement possible to construct the bridge structure this year. The ~I.ternative Selected approximate grade of the finished bridge will be the same as the existing Winburn Way grade. The Otak consulting team has been working with the The decision was made to use a Con Span pre-cast arch Ashland community for the past several months to bridge/culvert system- In addition to cost savings because develop flood damage reduction strategies and to the Con Span is prefabricated, this structure can be identify improvements to reduce the risk of flooding assembled in a short time period to further reduce costs and this next year. During the New Year's Day flood, in-stream impacts. significant damage occurred primarily because of the inadequate capacity of the Vmburn Way culvert A hydraulic computer model called HEC-RAS, developed which magnified the flood's effects. The existing 141- by the Army Corps of Engineers Hydrologic Engineering foot concrete culvert is now scheduled Center in Davis, California, has been prepared and «'•'•'an to be replaced with a 72-foot wide calibrated using newly collected topographic data. The Orr bridge structure that will have a span of model was used to examine various improvement scenarios 32 feet. A prefabricated bridge for the Creek and to evaluate different alignments and span ' structure has been selected to replace widths for the Con Span bridge, which is being designed to ' the culvert at Winburn Way. It may be convey the 100-year design storm event look like a balcony, for sitting or viewing. Participants Special Meeting Held were also supportive of the concept that the proposed flood wail in Lithia Park be designed to complement the To Gather Citizen appearance of the bridge design. Input on Bridge Design Because the bridge replacement project is only one of the many solutions that will be recommended, the temporary strengthening of the Creek banks will be On August 7, 1997 a special public meeting was held necessary until permanent improvements can be built. in Ashland to evaluate the architectural and design The use of rip rap and very large river rock (boulder) elements of the Con Span bridge which will replace along the west stream bank were discussed as possible solutions. Participants emphasized their desire, that rip rap if used as a temporary solution, be replace with :.z 4 permanent improvements at the earliest possible date. k J, ~Y. Tie New Years Da Storm Rated As A Big One .N 1 Of course we all know that the New Years Day flood was a devastating event, but how big was it? According j ; : • to results of a detailed hydraulic analysis performed by cav { S}Q,►., Otak, the New Years Day Flood has been rated as a 50 to 100 year return period flood event. the existing Winburn Way Culvert. Approximately 20 If this flood was a 50 to 100 year storm event, then why people participated together with the Otak consulting have we seen five devastating flood events over the last 50 years? Larry Magura explained, "It is like having 99 team and city staff. Brian McCarthy, a landscape white marbles and one black marble in a bag. You architect retained by the Ashland Parks Commission, reach in and have one chance in one hundred that you assisted the group by presenting a possible design for will pull out the black marble. But every year you still the bridge. The participants then broke into groups have that same chance of pulling a black marble out of and began to formulate their own bridge designs. the bag." It just so happens that five times in the last There was an overwhelming agreement that the bridge fifty years Ashland has experienced unusually large flood events on Ashland Creek, and it is just as likely structure should have features similar to the Atkinson that the City could have another large flood event next Memorial Bridge in Lithia Park. A suggestion to year. include a cantilevered section in the middle part of the bridge also receive significant support. The cantilevered idea, presented by Marilyn Briggs, would According to Otak's preliminary engineering analysis of flooding conditions, problems begin to occur along Other features of the proposed bridge included the use Ashland Creek when flows in the creek reach 850 cubic of lamps, railing, and color tinting the concrete to give- feet per second, (cfs) hydraulic capacity of the existing it a more aged look Participants at the August 7th Windburn Way culvert. This is a discharge equivalent to meeting suggested cutting costs by not including light about a two -year flood event. standards on the bridge. Many others however favored the classic look of lights on the bridge. Tie Biggest Problem Is - Identi ied Budd e .I~Tas Other Benefits f The Winbum Way Crossing replacement project will The most significant constriction in Ashland Creek also provide better riparian habitat than the pre-disaster affecting flooding in the City is the Winburn Way culvert. Since the Con SpanC replacement structure is Crossing. Hydraulic data from the HEC-RAS model a bridge, Ashland Creek can be restored to an open confirms that flood damage can occur when flooding stream bottom where the culvert now is. The new span exceeds the 10 year will cross over storm event. - - ~I the Creek, r .ascr.+e9 + . rw..- ar ties allowingwater- Even though " ~,s historically there have Z to flow down the natural creek been consistent bottom, rather periods of 10 to 15 than confining it years between serious ` in a concrete- flood events in+ 46f,. c` bottomed Ashland, it is also culvert, which is possible that the City v _ _ not "fish could see another ~ F friendly." The devastating flood this existing culvert next year. W11N3URN WAY BRIDGE 4EW i1[' pflSIS~ ASHLAND. ORFAON is 141 feet long, with a concrete In an effort to reduce bottom. The proposed new crossing will be 72 feet long the risk of flooding, the City has initiated plans to and will have a natural bottom. Conversion of this reconstruct the Winburn Way Culvert. This narrow section of Ashland Creek to a natural stream channel culvert, which extends for a distance of 141 feet, will be will significantly improve the aquatic habitat in replaced with a prefabricated concrete bridge structure that Ashland Creek. Ashland's citizens have expressed a will be designed to convey a 100 year flood event The strong interest in improving the riparian habitat along new bridge structure will be only 72 feet in width with an the creek. Creating a project with positive ef'ects on open stream bottom. the environment will help to satisfy this citizen foal. Public Focus Meeting Public Focus Meetings on the Ashland Creek Restoration Project have continued throughout the summer. The meeting schedule was modified to add the August 7th meeting, focusing on the Winburn Way Bridge Replacement. The last scheduled meeting in the series was scheduled for :l August 18th at Pioneer Hall and discussed results of the hydraulic modeling effort on Ashland Creek. Meanwhile, up in Lithia Park.... analyzed, and will be presented on annotated maps of the creek corridor. Who were those people wearing hip-waders walking around in Ashland Creek with cameras, One of the objectives of this task for the Parks clipboards, measuring tapes, and snorkeling Commission is to develop recommendations for gear? Scientists on the Otak consultant team rebuilding or abandoning trail segments and have conducted a thorough assessment of the bridges lost in Lithia Park during the flood. Ashland Creek corridor from Hersey Street Consultant team members met with the Park upstream to the swimming reservoir. The Commission in early July and went for a "stream assessment documented stream geomorphology, walk" to look at the flood damaged areas and fish and wildlife habitat, and identified areas discuss options. A series of public Park with existing or potential problems, such as bank Commission meetings has also been initiated to and slope instability. This information is being involve the community in this process. The next meeting will be in early September. For more information: Written comments may be addressed to: Ashland Creek Flood Restoration Project Ashland City Hall 20 East Main Street Ashland, OR 97520 If you want to be added to the project notice list, call Greg Scoles, Assistant City Administrator at (541) 488-6002. You may e-mail the consultants at cdagroup@transport.com or contact them directly at (503) 227-3487. vUi y ti y =J U U U rA ~ U U_ ~ O L .L y ~ L y C3 y N U _y y - - > .0.. O ~ OU O ~ U U y - C y c1 U L_D a. <n cC O c3 ~ O ~ :c n y v U C 'as tj y II. c: T 1~r ►1 O O 3 y ~ O ~ , ~ C3 U ~ V J ca.. R > T u O T U Q ~ ~ ~ '"'3 _ w ~ ~ U U li -2 O L ~ ^f.~. 'Q N VI U y U G bA y y y y C It) O G Q O w w. '~''y p r y T c~ C c~ rn C lF--~, U O C~ y O O r1. v~ U N^_ V1 1 Q ay+ L \ ^ ^ Jl C .L L 73 z c aai o L 3 3 L o r- -ca Y--i z G O O N L GJ `+O•' c vi > ca 1) 0 C. cC 3 L U CC N 'O C) N y J V) i O U ° cu ° 3_ ~s 3 3 U rn 'Q C1 GN :C C. ` cC A i O ;6 ~ > ~ Yyfl. N Fr-r. U _ U a. y ca O 1 cs ^ O C3 Z U W :O O c3 L O y C y Ly - L U L L U `1 r s ti) U C ^ y > y U r L J CS V y ^ sa. 7) CL o 3 y N ^ V--. rL. rn ~n C y ^ 25 L.r y y 0 U U~ ~ C '7 ~ X c^1'y' y CZ cz -7 N ~y 'r1 f I( QJ - r` C"i C Q O 'O c>~' v ~ O APPENDIX TWO to Ashland Creek Flood Restoration Project Final Report November 3, 1997 Ashland Creek Hydrologic Investigation Flow Magnitude Determination October 29, 1997 Submitted to: City of Ashland Ashland, Oregon Submitted by: Otak, Inc. 17355 SW Boones Ferry Road Lake Oswego, OR 97035 (503) 635-3618 Table of Contents - APPENDIX TWO Ashland Creek Hydrologic Investigation Page Purpose 1 Background 1 Approach 5 Methods of Analysis 7 Index Flood Method (IFM) 7 USGS Regional Equations 10 HEC-1 Flood Hydrograph Package (snowmelt not considered) 11 HEC-1 Flood Hydrograph Package (with snowmelt option) 14 Analysis 14 Discussion of Results and Final Recommendations 17 Selected Methodology 18 APPENDIX - References TABLES Table 1 25-year Average Snow Course Measurements for Ashland Ranger District 4 Table 2 Matrix of Hydrologic Method Requirements 8 Table 3 Gaged Watersheds Used by Index Flood Method 8 Table 4 Estimated Runoff from Various Hydrologic Calculation Methods 15 Table 5 Flows Calculated by Index Flood Method - Ashland Creek 19 FIGURES Figure 1 Area Topographic Map 2 Figure 2 Stream Gages Selected for Index Flood Method 9 Figure 3 Mean Annual Flood vs. Drainage Area Index Flood Method 12 Figure 4 Ratio to Mean Annual Flood vs. Recurrence Interval - Index Flood Method 13 Figure 5 Flowrate vs. Recurrence Interval for Various Hydrologic Calculation Methods 16 Figure 6 Index Flood Method Flow Rate vs. Recurrence Interval 21 ASH=F-TOC Purpose The purpose of this study is to estimate the magnitudes of flood events for various return periods on Ashland Creek in the City of Ashland. To adequately estimate flooding potential, the hydrology of the Ashland Creek watershed must be investigated and estimates made of streamflows corresponding to storms of various return periods. As a result of this hydrologic analysis, design recommendations can be made to improve conveyance capacity of the creek channel where hydraulic analysis indicates that capacity deficiencies exist. Background Ashland Creek flows through downtown Ashland, Oregon and has experienced five damaging floods during the last 50 years. Excessive precipitation in the Ashland Creek watershed often results in stream flows in excess of natural channel conveyance capacity which damage property and infrastructure in and adjacent to the creek. The January 1, 1997 flood event resulted in considerable economic losses, prompting the City of Ashland to retain the Otak team to assess the flooding potential and recommend improvements to the existing conveyance capacity of Ashland Creek. Ashland Creek has a 25.1-square-mile watershed at its confluence with Bear Creek, a tributary of the Rogue River in Southern Oregon. Located south of the City of Ashland, Oregon, the watershed ranges in elevation from 1882 feet at Winburn Way in town to 7533 feet at the Mount Ashland ski area. The stream has an average gradient of nine percent (see Figure 1) and averages a three percent gradient within the City limits. The watershed is heavily forested with early to late successional Douglas fir and ponderosa pine. Timber harvesting activity occurred in the watershed during the period of 1959 -1969 and affected seven percent of the total watershed area (Bear Watershed Analysis, 1995). During this period, the total length of roads in the watershed increased to about 53 miles. A logging and road construction moratorium was imposed on the watershed in 1969. Restricted public access to roads in the watershed has provided a relatively undisturbed and pristine drainage area. Aggressive wildfire suppression has resulted in increased fuel levels in the watershed. In 1959, a large fire threatened the watershed but its progress was stopped below Reeder Reservoir (BWA, 1995). Clearly, a major fire would change the nature of the hydrology of the watershed, resulting in increased erosion, slope failures, runoff, and higher peak flow rates generated from areas that were burned. The City of Ashland obtains its municipal water supply from Reeder Reservoir, a 20-acre impoundment downstream of the junction of the East and West Forks of Ashland Creek. Reeder Reservoir was created by the construction of Hosler Dam Ashland Creek Hydrologic Investigation 1 otak P: \ PROJECT\7800\ 7844 \ FI.DREPOR\APPEYDB \ HYREPORT L aan i:l au5 , ,000Z=„ L deed nog pjsjS 'Puel4wW '1W 1PuBI4SV luelel 9de a BueiW I PerO .5'L S9Sf1 :eomoS ,•~,~,r~;~~: « i~`I I . .411 OI , Ui a nlr ,nrLtlV 1 4b 4b 10 S~ 1p 1 to / a e ~ .I I ~ Ll 8L r ♦ I li ,'r,, i e d 11~i I 1 1 I 4 - l p~ Z ♦ % J C nl 1 I- Il 40, Q 3 H S H 3 1 V M a N V I N s V J a b I 1 ,!v~listJ ?y I _ 1 I V N o r r. V N H - u' ? I 1 M cl 1 J YI 1 t' ~ rn { • li i c I r ♦r m J ♦e ~T~ C 1 I J. 1 I ~ 1 J i 1 1 ~1 fill ♦ r , J I 1 g314SHA,LVM UNV-111SV J 1 U 3 II S H :.I 1. V M (1 N V I H s V ♦ I 1= / I 1 rrrrrra- r - i J a. s 3 a o1 ~ 1 V n[ o[ i V ti It 41P I W r) rv 3 ~I i e r a 3 !1 I a (1 J o a ~~i x • ~M ems, ~ N/ , , it ` _ 1 I I' f ! ~ 1 l ~ .t' I I f I 1 i 1~ I i 1 ♦ r',- i 1 1~ i 1 1 ~ 1♦ 1 ~ 11 I i , I i 1 1 41 f G J I'r ~ I f' 1 o r ti 1 1 r i I 11 , r I : 1 I ] I I y % r , ♦ ar a I I 1 J.. S e I { k. l I'.. ~ ♦ lam, / t - f,. I . .-.1 " I J _r e I I 1 i . a I ' . I 7 r Nof: c.t ,..p~og • fie:©3H 17r♦ 40 I n _ 4-- ~I . 1 V~II--ISV . 1 QM • • +•.'rr.i t ti' ~ 1.'(tl.: . . in 1928, which has an uncontrolled spillway that has minimal routing effects on flood flows from the upper Ashland Creek basin. Sediment deposition can be significant in the reservoir and has been well documented by Brazier (1975). During the December 1974 flood, the City shut down its water supply due to high suspended sediment concentrations in the reservoir. Typical non-storm releases from Reeder Reservoir contain little suspended sediment, but the 2.95 miles of Ashland Creek channel above Ashland are subject to massive sediment loads as a result of debris flows and local slope failures. Large woody debris is transported to the stream channel as a result of slope failures, and during high flows. This debris is mobilized and moved downstream where it causes channel blockages and temporary debris dams which reduce the conveyance capacity of the creek and increase the risk of damaging flood surges when the debris dams eventually break. Ashland Creek watershed soils consist of Tallowbox gravelly sandy loams, which correspond to SCS hydrologic group C (Soil Conservation Service, 1994). The underlying geologic formation is the Mount Ashland Batholith, which includes granitic rock structures that are readily decomposed and contribute to the typical rounded stream cobbles and coarse sand seen in Ashland Creek. The weathering of granite rocks commonly produces three distinct zones which are easily distinguished by their physical properties (Wilson, 1975). These zones are soil, decomposed granite, and disintegrated granitics. The soil zone is generally composed of silty sand to sandy silt, and ranges from a few inches to about one foot in thickness. The decomposed zone, produced by chemical weathering, is weaker than the disintegrated zone, and there is evidence that the types of slope failures common to the watershed originate in the decomposed zone. Field observation and analysis by Wilson (1975) indicate that these failures are a result of liquefaction of the granitic non-cohesive weathered material. The disintegrated zone, produced by physical weathering, is commonly distinguished by the appearance of fresh rock. Slab failures along weak joints and erosion along small gullies are the most typical failure modes for this formation. The characteristics of these geologic formations explain the kind of slope failures that contribute sediment to the stream channel in Ashland Creek and the expected gradation of particles that are transported during flood events in the watershed. The climatic regime of the Ashland Creek watershed is heavily influenced by orographic effects and its location in the eastern Siskiyou Mountains (Latitude 42E08' and Longitude 122E43'). This area of Southwestern Oregon has the lowest annual precipitation and the highest annual summer temperatures for the west side of the Cascade Mountains. At Ashland (elevation approx. 1,800), the average annual rainfall is 18.68 inches. At the 3,500-foot level, about 30 inches of rainfall occurs on average, and at the crest of Mt. Ashland (elevation 7,533 feet), 60 inches of precipitation occurs. Wintertime snow course records which record snow Ashland Creek Hydrologic Investigation 3 otak P: \ PROJECM 7800 \ 7844 \ FCDREPOR IAPPENDB I HYREPORT depth, water content, and density at several locations in the vicinity of the Ashland Creek watershed on a monthly basis are available from the Ashland Ranger District. Snow is unusual in the City of Ashland, but the higher elevations in the watershed have annual snowpacks that are a significant part of the hydrology of Ashland Creek. Table 1 presents 25-year average measurements for three snow course sites in or near the Ashland Creek watershed. Table 1. 25-year Average Snow Course Measurements for Ashland Ranger District Course Average Snow Average Water Density Depth Content Ski Bowl Road (6,000') 55.6" 23.5" 41.7 Switchback (6,500')* 80" 32.8" 40.7 Caliban II (6 500')* 77" 32.7" 41.9 * Snow course located in Ashland Creek Watershed Temperatures in the watershed vary significantly due to elevation, with summertime temperatures at Ashland being 15-25EF higher than mid- and high- elevation areas in the drainage basin (BWA, 1995). Wintertime temperatures vary with elevation but are typically 15E-20EF warmer at Ashland than at mid- to high-elevations in the watershed. During winter and spring, rain-on-snow storm events at mid-elevations can occur which contribute to high runoff and surface erosion. These mid-elevation areas are part of a transient snow zone generally occurring in the 3,500'-5,000' elevation band in the watershed. This elevation band comprises 42% and 51% of the Ashland Creek East and West Fork drainage areas, respectively. For this reason, rain-on-snow storm events in the watershed are significant to the hydrology of Ashland Creek. The history of damaging floods on Ashland Creek is well documented over the last 140 years, although actual streamflow records are limited throughout that entire period. Contemporary newspaper accounts provide much of the historic record about major flood events in the eastern Siskiyou Mountains (USFS, BWA). Winter storms have historically brought the devastating floods to the stream courses of southwestern Oregon. The most severe floods on Ashland Creek occurred in 1853, 1861, 1890, 1927, 1948, 1955, 1964, 1974, and 1997. Peak flows were measured by USGS stream gages on the East and West fork of Ashland Creek during 1924-1932, 1954-1962, and 1974-1981. High flows destroyed the gages on both streams on January 15, 1974, but peak flows for each stream were estimated by the slope area method, using high water marks to estimate the flood water surface elevations. Peak flows of 5,630 cfs (t25%) and 4780 cfs (t15%) were Ashland Creek Hydrologic Investigation 4 otak P: \ PROJEM 7800\7844 \FLD REPOR\APPEN DB \ HYREPORT calculated for the east and west forks, respectively. These extreme flows are a result of debris dams breaking and sending massive flood waves down Ashland Creek. The January 1974 flood was a localized flood event that deposited 130,000 cubic yards of sediment into Reeder Reservoir. Typical yearly sediment yields to Reeder Reservoir are on the order of 2,000 cubic yards per year (Wilson, 1975). Approach fwthe various return period Since it is important to establish reliable estimates as made of the available streamflows in Ashland Creek, careful consideration methods and data for simulating streamflow in a mountainous, forested watershed like Ashland Creek. A practical approach to estimate the return period of various flow in Ashland Creek is based on the availability of a long period of record for Ashland Creek which would allow statistical analysis with reliable results. The period of record for two gages which were placed on the east an d west forks of Ashland Creek is limited flow data is not non-consecutive sufficient to producer periods spanning 60 years. Annual peak accurate estimates of expected peak flows in the Ashland Creek Watershed. Agaged flow shland Creek. records, alternative Considering the limited duration of actual methods were required to estimate flows in the A variety of well-established hydrologic simulation software isavailable o Engirt ere U.S. Environmental Protection Agency (EPA) and U.S. Army CrPs (COE). These models require detailed description these distributed parameter and physical properties. The limitations of some of models are the large amounts of data required to calibrate and validate the model, and the time needed to build such k of F sufficient land Creek, this type of model was not selected because of the ac calibration data. These models do not explicitly account for debris loading in streams or for landslides that carry debris to the stream. Debris loading design requires observation of the watershed, knowledge of past storm chnealndtudge expected nt to make allowances for debris being conveyed ihe creek _ that the 100-year flood estimate, when used aisctures again t the effects of debris adequate 100-year protection of hydraulic s ri loading on Ashland Creek. Some of these models are capable of modeling sediment transport inclu dgent bedload and suspended load. Sediment do little ato help define the expected flood stream like Ashland Creek would heights since flood heights are dominated by local backwater effects and channel geometry. Other methods are readily available which provide adequate estimates of streamflow and do not have the complex data requirements of distributed Ashland Creek Hydrologic Investigation ot5 P: \ PROJEM 7800 \ 7844 \ FLDflEPOR\APPENDB \ HYREPOV parameter hydrologic models. Three commonly used methods for estimating streamflow on ungaged watersheds are the USGS regional equations, the Index Flood Method, and the COE HEC-1 model. These methods require varied input parameters, but all are capable of providing flow estimates that cover the range of anticipated flows. These methods were selected for use in the Ashland Creek hydrologic study. The results of these methods were compared and peak streamflow rates estimated for the 2-, 5-, 10-, 25-, 50-, and 100-year recurrence interval flows. The concept of recurrence interval is used to describe the average frequency of a particular flood event. For example, a 10-year flood event is a flood event with a peak flow magnitude that is equaled or exceeded one time every 10 years. The probability that a particular flood will occur in any given year is the reciprocal of the recurrence interval (1/10 or 0.1 for the 10-year flood event). For most natural streams, the proportional increase of flood magnitudes decreases with increasing return period. As explained in the City of Ashland Flood Insurance Study (FEMA, 1980): "Although the recurrence interval represents the long term average period between floods of a specific magnitude, rare floods could occur at short intervals or even within the same year. The risk of experiencing a rare flood increases when periods greater than 1 year are considered. For example, the risk of having a flood which equals or exceeds the 100-year flood (1 percent chance of annual occurrence) in any 50-year period is approximately 40 percent (4 in 10), and, for any 90-year period, the risk increases to approximately 60 percent (6 in 10)." Recurrence intervals are assigned by engineers and planners as a means to estimate flooding risk and determine a basis for design of flood protection and flow conveyance structures. The role of sediment transport in the flood hydrology of Ashland Creek was initially considered, but ultimately not factored into the conclusions of this study. It is recognized that large amounts of sand and silt are transported during large peak flow events, and the effects of such storms on sediment deposition in Reeder Reservoir are well documented. Based on discussion with city maintenance staff, the Winburn Way culvert became plugged with decomposed granitic sediment during the January 1, 1997 flood event. This indicates that significant volumes of sandy sediment is transported through the creek system by floods of this nature. Deposition of sediment in the Winburn Way culvert was influenced by a channel blockage at a wooden deck structure that was built partially over the creek channel downstream of Winburn Way. Sediment transport, therefore, is only significant if bed elevations change in the channel in such a way as to reduce the hydraulic capacity of the channel. Personal communication with Dr. Tatsuaki Ashland Creek Hydrologic Investigation 6 otak P:\PROJECC\7800\7844\ FLDREPORIAPPENDB\ HYREPORT Nakato of the Iowa Institute of Hydraulic Research at the University of Iowa verified that the effects of suspended and bed load sediment in flood flows do not require any increase in the water surface elevations computed by a "clear water" hydraulic model such as HEC-2 or HEC-RAS. At high flows, the bed friction factor for a given reach becomes lower because the channel bed becomes smoother. This phenomena reinforces the thought that, although much sediment is carried by Ashland Creek during high flows, it is not reasonable to increase flood elevations calculated by a hydraulic model to account for sediment transport unless it can be shown that the stream bed elevations change significantly during these events. Reports on the January 1997 flood by Ashland city staff indicate that during peak flows in the downtown area, boulders were transported as bed load and made loud noise from impacts with each other and the armored channel bed. This mechanism can only be accounted for in a hydraulic model by selecting appropriate channel flow resistance (roughness values). No other adjustments to the Ashland Creek hydrology need to be made to account for sediment transport. Confirming observations of the creek channel following the 1997 flood event by Otak staff verified that deposition of sediment in Ashland Creek does not appear to contribute to increased flood heights and therefore need not be considered in the development of basin hydrology. Methods of Analysis Calculation of the peak flow rate for various storm events was achieved by analyzing the Ashland Creek basin using three separate methods: USGS regional equations, the HEC-1 flood hydrograph model, and the Index Flood Method. Table 2 is a matrix showing the required input parameters and the expected reliability for each of the proposed methods. The following sections describe the procedures followed for each method and the results achieved. Index Flood Method (IFM) The Index Flood Method uses stream flow data from other drainage basins with hydrologic characteristics similar to the Ashland Creek basin to estimate flows. This method uses statistical data from each gage in other basins and incorporates all the data into graphical summaries. Peak annual stream flow data for gaged watersheds in the vicinity of Ashland Creek were obtained from the USGS surface water data web site (http://water.usgs.gov\swr\OR\). Figure 2 shows location of selected gages. Table 3 presents information about these gages. Ashland Creek Hydrologic Investigation 7 otak P:\PROJECC\7800\7844\FUREPORUPPEYDB I HYREPORT Table 2. Matrix of Hydrologic Method Requirements Index Flood USGS Regional Eqs. Inputs Method HEC-1 Method Area ✓ ✓ ✓ Land use NA ✓ ✓ Precipitation Intensity ✓ ✓ ✓ Precipitation Time Series NA NA ✓ Watershed Characteristics ✓ ✓ ✓ Statistical ✓ ✓ NA Empirical ✓ ✓ NA Deterministic NA ✓ ✓ Channel Routing NA NA ✓ Outputs Index Flood USGS Regional Eqs. HEC-1 Method Method Hydrograph NA NA ✓ Peak Q ✓ ✓ Relative Time of Calculation Lon Short Lon Table 3. Gaged Watersheds Used by Index Flood Method Gage Location Gage Drainage Elevation Period of Number Area (MSL) Record Rogue River Near Prospect 14328000 312 2620' 1908-1994 Elk Creek 14337800 78.8 1813' 1973-1994 West Branch Elk Creek 14337870 14.2 1773' 1973-1989 Grave Creek 14371500 22.1 2354' 1939-1989 Middle Fork Applegate 14361590 50.7 2002' 1980-1987 Elliot Creek 14361600 51.8 2024' 1978-1987 Carberry Creek 14361700 68.9 1990' 1978-1987 East Fork Illinois River 14372500 42.3 1780' 1941-1991 Sucker Creek 14375100 83.9 1714' 1966-1991 Illinois River at Kerb 14377100 364 1232' 1926-1991 Ashland Creek Hydrologic Investigation S otak P: k PROJEGTk 780017844\MDREPORUPPENDB% HYREPORT } Study Area LEGEND I Stream Gage Locations I Major Roadways City Boundary i County Boundary L I i j I I ~ I t Suiherlin i t L C 0 S Roseburg I 00UGt_AS r 0 Elk Creek f r°r^ `D14337800 Rogue River t . _ 14328000 ..r ..I,I~. r.•-..~...^-t~ ~ .L } r1 -3 Y~.. r• `'-tit J,- X14337870 Prospect _ - rte- L7 West Branch tf Grave Creek Elk Creek -D 14371500 CURRY% t Cants Pass JOSEPHINE - Medford 7 t Illinois Iver I t..t t at Kerb i 'D143771 0 Sucker Creek i '714375100 C" ASHLAND + f i Carberry Creek East Fork '14372500'4361700 Illinois River P._-14361590 Middle Fork Applegate River 1 `14361600 Elliot Creek Figure 2. , Stream Gages Selected 1" = 15 miles for Index Flood Method Oct. 27, 1997 15 miles 0 15 miles h:\project\9100\9199\gis The Index Flood Method requires that peak flow flood-frequency curves be developed and fitted for each gage location using the Log-Pearson Type III distribution with appropriate skew factors based on gage location. To accomplish this, annual peak flow rates from each gage were obtained from the USGS and fitted using standard statistical methods. The use of Computer-Aided Hydrology and Hydraulics (CAHH, 1994) engineering software simplified this task. From the Log-Pearson curve, the mean annual flood was determined. The mean annual flood is defined as the flood event with a recurrence interval of 2.33 years. Mean annual flood values are plotted against drainage area for each gage, as shown in Figure 3. The 2-, 5-, 10-, 25-, 50-, and 100-year recurrence interval peak streamflows for each gage are also selected from the Log-Pearson curve, divided by the mean annual flood, and plotted on Figure 4. The Index Flood Method is discussed in more detail by Viessman et. al. (1977). By using Figures 3 and 4, it is possible to estimate the flows in Ashland Creek at Winburn Way based on the drainage area at this point (24.1 square miles). Using Figure 3 and 24.1 square miles on the x-axis, the intersection with the fitted line (based on a logarithmic regression) from the other gaged basins corresponds to the mean annual flood for a 24.1-square-mile area, which is 1,080 cfs. Referring to Figure 4, the Grave Creek 100-year recurrence interval ratio is 3.05. To calculate the 100-year flood on Ashland Creek at Winburn Way, based only on the Grave Creek ratio, multiply 1,080 cfs by 3.05. This gives a value of 3,300 cfs. The data from each of the stream gages was analyzed and hydrologic characteristics and period of record for each of the ten gage areas were compared to select the most representative gages. West Branch Elk Creek, Grave Creek, and East Fork Illinois River were ultimately selected for use in computing the expected peak flows in Ashland Creek by the Index Flood Method. These gages were considered to be the most hydrologically similar to Ashland Creek, had adequate periods of record, and were closely grouped throughout the range of recurrence intervals. For final calculations, a log-Pearson Type III regression line was fitted through the three selected gage data which resulted in composite ratios for all recurrence intervals. (The log-Pearson Type III distribution is a common hydrologic distribution for determining peak flow.) The composite ratio for the 100-year return period is 2.87. Multiplying 1,080 cfs, by 2.87 results in a 100-year flow of 3,100 cfs. In this manner, the 2-, 5-, 10-, 25-, and 100-year flood estimates were made. USGS Regional Equations The USGS regional equations provide a fast and reasonable estimate of stream flows with various recurrence intervals. The development and use of regional flow equations are described in "Magnitude and Frequency of Floods in Western Oregon" (Harris et. al., 1979), which is included in the Oregon Department of Transportation Hydraulics Manual (January 1990). The Harris report is based Ashland Creek Hydrologic Investigation 10 otak P:\PROJECC\7800\7844\FLDREPOR\APPENDB\HYREPORT Figure 3. Mean Annual Flood vs. Drainage Area 100000 Index Flood Method 10000 0 o U- cz A 1080 - - - - - ~ 1000 ' I i i i i 100 24.1 10 100 1000 Drainage Area (square miles) ASHLAND CREEK FLOOD RESTORATION PROJECT HYDROLOGY REPORT Incorporated w• Figure 4. Ratio to Mean Annual Flood vs. 5 Recurrence Interval - Index Flood Method Stream Gages ---E3- Rogue River near Prospect Elk Creek W. Br. Elk Creek 4 Grave Craek ~m -0- M.F.applegale Elliot Creek O Carberry Creek E.F. Illinois River Sucker Creak Grave Creek o - - - - - `?E.F. Illinois River cz 3 - -Q-- Illinois River at Kacby - - - - - 3' - . Br. Elk Creek C ~ .ms O 2 CU - / 0 2 5 10 25 50 100 Recurrence Interval (years) ASHLAND CREEK FLOOD RESTORATION PROJECT HYDROLOGY REPORT Incorporated a on all unregulated streams (or regulated streams prior to their becoming regulated) where gaging stations have been operated for at least ten years. For the High Cascades region, which contains Ashland Creek, 28 Oregon stations were used to develop the regression equations. Multiple regression analysis was used to correlate flood discharges with selected basin characteristics and to develop appropriate regional relation equations. Only the most sensitive characteristics were retained as parameters for use in the equations. To estimate the 100-year flood on Ashland Creek, the following equation was used: Qo.01(100) = 22.6A°-81(ST+1)-1.17(101-F)0.03I1.57 (72% standard error) where Qo.01(100)=100-year flood, A=drainage area, ST= area of lakes and ponds (percent), F=forest cover (percent), and I=24 hour rainfall depth (inches) based on the Oregon isopluvial map (NOAA, 1973). The equations for other return periods are identical except in the selection of the coefficients. For Ashland Creek, A=24.1, ST=0.14%, F=97%, and I=3.0" which gives 1,493 cfs as the 100-year flood estimate by the USGS regional equations. Standard error is a statistical measure of the variability and reliablility of the results of the regional runoff equation. The standard error for the 100-year recurrence interval equation is 72% which means that the standard deviation of the distribution has a magnitude of 72% of the expected value. This magnitude of error is not acceptable for the accuracy required for the flow estimate in Ashland Creek. HEC-1 Flood Hydrograph Package (snowmelt not considered) The U.S. Army Corps of Engineers (COE) Hydrologic Engineering Center at Davis, California developed the HEC-1 model to simulate the surface runoff response of a river basin by computing runoff, routing flows through stream channels, and computing hydrographs at desired locations in the river basin (HEC-1, 1990). When snowmelt is not considered, the input file for HEC-1 describes the precipitation depth for a particular return period storm and time distribution, times of concentration, basin drainage area and land use properties of drainage subbasins, stream channel dimensions, stream channel roughness, reach lengths, and the arrangement and connectivity of subbasins in the stream network. To study Ashland Creek by the HEC-1 method, the watershed was divided into nine subbasins, and the stream connectivity and channel parameters were defined. Given this information for the Ashland Creek watershed, HEC-1 peak flows were generated for Ashland Creek. The HEC-1 methodology is widely accepted for use in estimating peak flows from undeveloped, ungaged watersheds. Ashland Creek Hydrologic Investigation 13 otak P!\PROJECr\78M\7844\FLDREPOR\APPEYDB\HYREPORT This methodology was specifically developed for use on undeveloped, agricultural areas and not the mountainous, forested terrain of the Ashland Creek watershed. Another limitation of this model for application to the Ashland Creek watershed is that the simple rainfall runoff relationship described above is not representative of the rain-on-snow storm events that historically produce floods like Ashland experienced on January 1, 1997. The complete HEC-1 input file (with no snowmelt option) is included in the Appendix to this report. HEC-1 Flood Hydrograph Package (with snowmelt option) HEC-1 has the ability to model snowmelt which makes the application of HEC-1 more representative of damaging wintertime storm events in the Ashland Creek watershed. When considering snowmelt, HEC-1 requires the water equivalent depth of snow, the temperature lapse rate, melting coefficients. The watershed must also be partitioned into subbasin elevation zones which have similar snowmelt parameters. Runoff curve numbers are not used for the snowmelt routine. For the snowmelt simulation, the Ashland Creek Watershed was divided into four incremental elevation zones and the Clark Unit Hydrograph method was used to route the snowmelt and runoff to Winburn way. Selection of appropriate input parameters is critical to achieve acceptable results. For the snowmelt simulation, this includes estimation of a daily time series temperature distribution for the Ashland Creek watershed, annual precipitation depths in each of the elevation zones, estimation of the Clark storage parameter which influences the shape and magnitude of the runoff hydrograph, and snow depth in each subbasin. Snow course records for the last 25 years were obtained from the City of Ashland and the Forest Service for four stations in and around the Ashland Creek watershed. Snowpack depths for each HEC-1 snow basin were estimated from the 25-year average snowpack at each snow course. Average snowpack data was used due to the conservative nature of the HEC-1 model and the inherent uncertainty in the selection of model parameters. Temperature for the watershed lapse rate and annual precipitation information was obtained from the office of the Oregon State Climatologist located at Oregon State University. The complete HEC-1 input file (with snowmelt) is included in the Appendix to this report. Analysis Using the four methods, the 2-, 5-, 10-, 25-, 50-, and 100-year peak streamflows for Ashland Creek were estimated. The results obtained are presented in Table 4. For purposes of comparison, the comparable return period discharges used in the 1978 FEMA Flood Insurance Study for Ashland Creek are also included in the table. Figure 5 is a flowrate vs. recurrence interval plot of these results. Each set of data is log-fitted to allow interpolation. Ashland Creek Hydrologic Investigation 14 otak P\PROJECi'\7800\7844\PLDREPOR\APPEHDB\HYREPORT Table 4. Estimated Runoff from Various Hydrologic Calculation Methods. Index USGS HEC-1 HEC-1 Recurrence Flood Regional Method Method FEMA Interval Method Equations without with (cfs) (years) (cfs) (cfs) snowmelt snowmelt (cfs) (cfs) 2 950 300 20 2200 240 5 1500 550 150 2350 530 10 1850 750 850 2500 827 25 2450 1000 1700 2700 1246 50 2700 1250 2600 2900 1723 100 3100 1500 3500 3000 2259 Mean annual 1080 NA NA NA NA flood Ashland Creek Hydrologic Investigation 15 otak P: \PROJECT\ 78M \7844 \FLDREPOR\APPENDB \ HYREPORT Figure 5. Flowrate vs. Recurrence Interval for I 4000 Various Hydrologic Calculation Methods I Methods • Q Index Flood Method USGS Regional Equations ® HEC-1 - No Snowmalt 3000 HEC-1 - With Snowmalt FEMA 0 U) 2000 r p ~F I °F ~t S .✓`f ser 1000 R 0 • 2 5 10 25 50 100 Recurrence Interval (years) ASHLAND CREEK FLOOD RESTORATION PROJECT HYDROLOGY REPORT Incorporated Discussion of Results and Final Recommendations The five methods used in this report to estimate peak flows in Ashland Creek each produce different results, which makes the selection of an appropriate peak flow discharge challenging. Evaluating the limitations of each computational method is one way to compare one set of results against another. Comparing the uncertainty of the results as a measure of each method's reliability is another way to evaluate the results. By observing the limitations and uncertainty associated with each method, selection of the 2-, 5-, 10-, 25-, 50-, and 100-year peak flows in Ashland Creek can be made. The Index Flood Method produced ten different sets of flows based on the various gages discussed in the Method of Analysis section of this report. For some engineering applications, it is reasonable to select the highest set of flows as the results of this method. This conservative approach is most appropriate when the sets of flows are based on all the gages that are closely grouped together. As seen in Figure 3, the flow curves based on all the gages in the sample are not closely grouped. A comparison of hydrologic characteristics, period of record, and the results of each of the ten gages was made. West Branch Elk Creek, Grave Creek, and East Fork Illinois River were selected to calculate the Index Flood Method flows for Ashland Creek. These three gages are the most hydrologically similar to Ashland Creek and the results of these three gages are closely grouped. A logarithmic regression was applied to these three curves resulting in the calculated 2-, 5-, 10-, 25-, 50-, and 100-year flows for Index Flood Method as shown in Table 4. The limitations of this method is the uncertainty in the hydrologic similarity and the period of record for the selected gages. By carefully comparing land use, elevation, topography, and proximity of the gages to Ashland Creek, the best estimates of streamflow are made. Two of the three selected gages have 50-year-long periods of record and the other has a 16-year period of record. These periods are sufficient to give estimates of various return period flow rates. The Index Flood Method includes the effects of snowmelt because all the gages used in this method measure flow from watersheds that are influenced by snowmelt runoff. The Index Flood Method provides a strong estimate of the hydrologic behavior of Ashland Creek. The USGS regional equations produced the lowest flow estimates among the five methods used. As discussed earlier, these equations were based on a multiple regression of 28 gages in the high cascade region of the state of Oregon. Because the high cascade region runs the entire length of the state, it is clear that some of the gages used in developing these equations represent streams and watersheds that are not comparable to Ashland Creek. As a result, the equations give a standard error measure for each return period which varies from 50 to 72 percent. Standard error is discussed on page 11. Ashland Creek Hydrologic Investigation 17 otak P:\PROJECM 7800\7844 \ KDREPORWPENDB \ HYREPORT The FEMA study results were based on a multiple regression of several gages in the Ashland Creek area. The FEMA study did not disclose what gages or multiple regression techniques were used, but the methodology produced results that are more reliable than the USGS regional equations because they are based on more localized conditions. A simple logarithmic regression was used to determine the FEMA flow rates for the return periods not published in the report. Since the techniques used to determine the FEMA flows were unpublished the FEMA results were considered unreliable for the design purposes of this study. Nearly 20 years has passed since the FEMA hydrologic study was conducted for Ashland Creek. During this time additional flow records have been recorded which the FEMA hydrology can not incorporate. The HEC-1 analysis without snowmelt shows the limitations of the HEC-1 model because the high frequency events (the 2- and 5-year flows) are obviously underestimated. The SCS infiltration and kinematic routing elements of the program reduce the peak flow to a minimal level. In fact, the 2-year return period event did not exceed 20 cfs, since HEC-1 was developed for agricultural areas and not mountainous forested areas. Although the lower frequency events (the 25-, 50-, and 100-year events) appeared to be modeled reasonably, as compared to the other methods, the HEC-1 methodology does not accurately represent the Ashland Creek hydrologic response for the range of precipitation intensities required for this study. The HEC-1 analysis with snowmelt incorporates a totally different precipitation excess and routing calculation than the no-snowmelt model. There are significant uncertainties associated with the snowmelt coefficients, snowpack and precipitation estimates, temperature and wind speed estimates, as well as the choice of Clark unit hydrograph parameters. These parameters were estimated with the best data and references available, but without extensive additional study, the snowmelt simulation has limited value. Still, the higher frequency events appear to be overestimated while the lower frequency events appear reasonable. For the snowmelt simulation, there appears to be a flow rate that is a result of snowmelt which is independent of precipitation. With increasing precipitation, runoff increases but the runoff appears to be dominated by snowmelt independent of precipitation, which does not follow observed hydrologic conditions in Ashland Creek. Selected Methodology The Index Flood Method was selected as the method that best represents the observed flood behavior of Ashland Creek. Table 5 shows the flows calculated by the Index Flood Method for Ashland Creek for various return periods. Ashland Creek Hydrologic Investigation 18 otak P: \ PROJECM 7800 \ 7844 \ FLDREPOR\APPE`iDB\HYREPORT Table 5. Index Recurrence Flood Interval Method (years) (cfs) 2 950 5 1500 10 1850 25 2450 50 2700 100 3100 Figure 6 is a log-fitted curve of this data Flow rates for recurrence intervals not calculated by the Index Flood Method may be estimated from this figure. The recommendation of the Index Flood Method is based on the following facts: • The Index Flood Method uses real data from nearby watersheds. • The nearby watersheds used in the Index Flood Method are hydrologically similar to Ashland Creek and include transitional zone elevation bands that experience rain-on-snow storm events. The greater uncertainties of the other considered methods lead to this recommendation. The USGS regional equations are a highly simplified approach which was developed with data from some gages that do not closely represent the Ashland Creek watershed. Although the statistical uncertainly is known for each return period, other information that has been developed for the watershed provides better estimates than the USGS regional equations. The FEMA streamflows, although accepted and used for the last 20 years, are not based on as wide a sample of gages as the Index Flood Method which includes more recent hydrologic data. The HEC-1 simulations involve limitations that are not acceptable when estimating flows for a wide range of return periods accurately. The limitations of using the HEC-1 model in mountainous forested areas are sufficient to not consider this method. The Index Flood Method evaluated ten stations in the Ashland Creek vicinity and showed the variation in results among these gages. Compared to the other four methods studied, the Index Flood Method produces the highest results, as can be seen in Table 4. The three selected gages were fitted with a regression equation and are near the middle of the range of variation for the ten gages and are clearly similar hydrologically to Ashland Creek. As Ashland Creek Hydrologic Investigation 19 otak P:\PROJECM7800\7844\PLDREPOR\APPEYDB\HYREPORT shown in Table 3, the elevations of these gages range from 1,773 feet to 2,354 feet and have drainage areas which include transitional zone elevation bands which experience rain-on-snow storm events. Ashland Creek also has significant portions of transitional zone drainage area, and the City of Ashland sits at about 1,800 feet. Additionally, the drainage areas of the three selected gages are relatively close to the 24.1-square-mile drainage area of Ashland Creek. This similarity is important because channel routing effects and non-homogeneous watershed characteristics have an increased effect on the hydrologic response of drainage basins as drainage area increases. The Index Flood Method produces a strong estimate of the hydrology of Ashland Creek because it is based on real data with a substantial period of record. At the same time, however, it is important that the City and property owners affected by the flood of January 1, 1997 understand that, despite the large amount of damage incurred, the return period for such a flood event may be more frequent than expected. The flows determined by the Index Flood Method for Ashland Creek are the result of a rigorus hydrologic study of the Ashland Creek watershed and may be used as as the basis of design of hydraulic structures in and near Ashland Creek. Ashland Creek Hydrologic Investigation 20 otak P:\PROJECf\780017844\FLDREPOR\APPF-NDB\HYREPORT N I Figure 6. Index Flood Method I 4000 Flow Rate vs. Recurrence Interval I I N 3000 I 13 U) I " C 2000 N o H Method ® Index Flood Method N 1000 N I I 0 2 5 10 25 50 100 I Recurrence Interval (years) I ASHLAND CREEK FLOOD RESTORATION PROJECT HYDROLOGY REPORT I Incorporated APPENDIX References: 1995 Bear Watershed Analysis (BWA, 1995), Ashland Ranger District, Rogue River National Forest, (various contributors). Wilson, Sandra A., Slope Stability and Mass Wasting in the Ashland Creek Watershed, U.S. Forest Service, Rouge River National Forest, March 1975. HEC-1 Flood Hydrograph Package User Manual, U.S. Army Corps of Engineers Hydrologic Engineering Center, Davis, CA, September 1990. Flood Insurance Study. City of Ashland, Oregon, Jackson County, Federal Emergency Management Agency (FEMA), Federal Insurance Administration, Community Number 410090, December 1, 1980. Viessman, W. Jr., Introduction to Hydrology, Second Edition, 1977, Harper and Row Publishers. Akan, A.O., Computer-Aided Hydraulics and Hydrology (CAHH) Users Manual, December, 1994. Harris, D.D., Larry L. Hubbard, Lawrence E. Hubbard, Magnitude and Frequency of Floods in Western Oregon, U.S. Geological Survey, Open File Report 79-553. Snow Course Records (1966-1997), Ashland Ranger District, USFS, USDA USGS stream gage records accessible via Internet. (http://water.usgs.gov \ swr \ OR) Soil Survey of Jackson County Area (SCS, 1994), Oregon, 1994, US Department of the Interior, Soil Conservation Service. Precipitation-Frequency Atlas of the Western United States, Volume X-Oregon, U.S. Department of Commerce, National Oceanic and Atmospheric Administration (NOAA), National Weather Service, Silver Spring, MD, 1973 APPENDIX THREE to Ashland Creek Flood Restoration Project Final Report November 3, 1997 Ashland Creek Hydraulic Investigation Stream Channel Improvements October 29, 1997 Submitted to: City of Ashland Ashland, Oregon Submitted by: Otak, Inc. 17355 SW Boones Ferry Road Lake Oswego, OR 97035 (503) 635-3618 Table of Contents - APPENDIX THREE Ashland Creek Hydraulic Investigation - Stream Channel Improvements Page Purpose 1 Background 1 Hydraulic Modeling Procedure 2 January 1997 Flood Event 3 Existing Ashland Creek 4 New Winburn Way Culvert Replacement Structure 12 Ashland Creek Restoration Priorities 15 Potential Ashland Creek Improvements 17 Summary 21 APPENDICES Appendix A HEC-RAS Background Information Appendix B Ashland Creek HEC-RAS Information Appendix C Ashland Creek Hydraulic Information Appendix D HEC-RAS Output Tables Appendix E Existing and Proposed HEC-RAS Input Files TABLES Table 1 Existing Culvert/Bridge Parameters 5 Table 2 Calle Guanajuato 100-Year Water Surface Elevations, Existing Conditions 9 Table 3 Priority Matrix for Culverts/Bridges and Reaches 16 Table B-1 Ashland Creek Hydrology App. B Table C-1 Building and Existing 100-Year Water Surface Elevations App. C A3 W.AMD.TOC Table D-1 HEC-RAS Output, Winburn Way Culvert Replacement Structure Only w/ Floodwall App. D Table D-2 HEC-RAS Output, Winburn Way Culvert Replacement Structure Only w/o Floodwall App. D Table D-3 HEC-RAS Output, Calle Guanajuato Reach App. D Table D-4 HEC-RAS Output, Lithia Way Culvert and Bluebird Park Reach App. D Table D-5 HEC-RAS Output, Water Street Culvert App. D Table D-6 HEC-RAS Output, Hersey Street Bridge App. D Table D-7 HEC-RAS Output, All Improvements App. D Figures Figure 1 Project Area Map 24 Figure 2 Location of Buildings and Culverts/Bridges 25 Figure 3 Location of Cross-Sections 26 Figure 4 Ashland Creek Water Surface Profile, Flood Event 27 Figure 5 Ashland Creek 100-Year Water Surface Profile, Existing vs. no Hydraulic Structures Conditions 28 Figure 6 Ashland Creek 100-Year Flood Boundary, Existing Conditions 29 Figure 7 Winburn Way only 100-Year Water Surface Profile w/ Floodwall, Existing vs. New Conditions 30 Figure 8 Ashland Creek 100-Year Flood Boundary, Winburn Way Improvements Only 31 Figure 9 Ashland Creek 25-Year Flood Boundary, Winburn Way Improvements Only Figure 10 Winburn Way only 100-Year Water Surface Profile, w/o Floodwall, Existing vs. Proposed Conditions 32 Figure 11 Calle Guanajuato 100-Year Water Surface Profile, Existing vs. Proposed 33 Figure 12 Ashland Creek 100-Year Flood Boundary, All Improvements 34 Figure 13 Bluebird Park Reach 100-Year Water Surface Profile, Existing vs. Proposed Conditions 35 Figure 14 Water Street Culvert 100-Year Water Surface Profile, Existing vs. Proposed Conditions 36 Figure 15 Hersey Street Bridge 100-Year Water Surface Profile, Existing vs. Proposed Conditions 37 Figure 16 All Improvements 100-Year Water Surface Profile, Existing vs. Proposed Conditions 38 Figure 17 Ashland Creek 100-Year Flood Boundary, All Improvements Back of Report ASHLAND.TOC Ashland Creek Hydraulic Investigation Purpose The purposes of this study are to estimate Ashland Creek water surface elevations and typical hydraulic capacities for the creek and structures, and to evaluate potential improvements to hydraulic structures in Ashland Creek. The outcome of this study is a prioritized list of recommended design improvements for reducing potential flood impact. This is accomplished by increasing conveyance capacities in selected reaches and designated hydraulic structures. The hydrology used for this hydraulic evaluation is based on a companion document titled "Ashland Creek Hydrologic Investigation." Background The City of Ashland retained Otak, Inc., to evaluate existing and potential hydraulic conditions (e.g., conveyance capacities, flooding extent, and water surface elevations) on Ashland Creek. Ashland Creek flows north through Ashland, Oregon from its headwaters in the Siskiyou Mountains to its confluence with Bear Creek. This report describes the detailed hydraulic evaluation of a 4,200-foot reach of Ashland Creek (Figure 1), from downstream of Hersey Street to upstream of the Butler band shell in Lithia Park. The latest flood event in Ashland Creek occurred from late December 1996 to early January 1997, resulting in major flooding along the creek. Presently located within this reach are six pedestrian bridges, seven culverts/ bridges, one paved drive over the creek, and several obstructions in or adjacent to Ashland Creek (cantilevered deck, adjacent nearby buildings, concrete dams). Figure 2 shows the general locations of these hydraulic structures and buildings. The culverts/bridges range in size from the Water Street twin culverts, with a combined open area of approximately 50 square feet, to the Southern Pacific Railroad (SPRR) culvert, with an open area of approximately 220 square feet. The scope of the hydraulic study is to analyze the existing hydraulic conditions of the reach, evaluate the proposed hydraulic improvements of the Winburn Way culvert replacement structure, and to prioritize and investigate other scenarios for potential flood impact reduction. The organization of the remainder of this report is as follows: • Description of procedure used in evaluating the hydraulic regime of Ashland Creek. • Evaluation of the January 1997 Flood Event. • Investigation of existing Ashland Creek hydraulic conditions. Ashland Creek Hydraulic Investigation 1 Otak P!\PROJECT\7800\7844\FLDREPOR\APPENDC\ASHLAND3.WPD 10.29.97 • Hydraulic evaluation of the proposed Winburn Way culvert replacement structure. • Prioritization of existing Ashland Creek hydraulic structures for potential future improvement/replacement. • Hydraulic evaluation of potential future improvements to selected portions of Ashland Creek. • Summary Hydraulic Modeling Procedure One of the first steps in the Ashland Creek modeling effort was a field investigation of the study reach by Lawrence Magura, PE (Project Manager) and Ben Higgins, PE (Project Engineer) of Otak on May 16, 1997. The entire 4,200-foot reach was walked to obtain an overview of the site. Discussions were held regarding location of cross sections to be surveyed, channel roughness coefficients to be used in the hydraulic model, high-water marks, and modeling techniques. On the same day, Larry Magura and Ben Higgins met with Stewart Osmus, PLS, of Marquess and Associates from Medford, Oregon, who provided topographic surveying services for the model development.. The entire reach was walked again and the locations of cross sections and specific features (e.g., high-water marks, culverts/bridges, adjacent structures) were marked for future field survey. The topographic survey for the studied reach was substantially completed by the end of June 1997. The quantity of survey data for the hydraulic modeling portion of the Ashland Creek Restoration Project included approximately 90 cross sections, culvert/bridge details (i.e., culvertibridge and road geometry), about a dozen high-water marks, and the finished floor elevations and geometries of adjacent buildings. All of the information was surveyed electronically using a common horizontal and vertical datum. The resultant electronic survey data was transmitted to Otak by the Internet and on a diskette by mail. The data included an AutoCAD drawing (with locations, point numbers, elevations, and a short description), cross section figures, and an ASCII file. The ASCII file is a data list showing the point number, associated Cartesian coordinates, elevation, and a short identifying description. The above information was used by the Otak staff to transfer survey data into geometric data usable for the hydraulic modeling effort. Hydraulic modeling of the 4,200-foot reach of Ashland Creek in the downtown area, under both existing and proposed (with improvements) conditions, was accomplished using the US Army Corps of Engineers HEC-RAS (Hydrologic Engineering Center - River Analysis System) computer software modeling program, Version 2.0, dated April 1997. The location of the cross sections used in the model are shown in Figure 3. Ashland Creek Hydraulic Investigation 2 Otak P:\PROJECT\7800\7844\FLDREPOR\APPENDC\ASHLAND3.WPD 10.29.97 Another visit to the site by Otak staff was made on July 10, 1997 for field verification, field measurements, and familiarization. Otak staff participating in this site visit included Lawrence Magura, Ben Higgins, Brady Fuller, and Stephan Blanton. Work on the hydraulic modeling portion of the Ashland Creek Flood Restoration Project continued through the months of July, August, and September. The hydraulic modeling work was coordinated with and supported the work of the Winburn Way design team to evaluate impacts of the proposed Winburn Way culvert replacement structure. Work also included concerns with prioritizing existing hydraulic structures and evaluating potential hydraulic improvement to Ashland Creek for the reduction of flood impacts. A brief description of the HEC-RAS model is given in Appendix A to this report. The underlying hydraulic input parameters used in the HEC-RAS Ashland Creek hydraulic model are described in Appendix B. January 1997 Flood Event The December-January flood on Ashland Creek is described below. It is based on eyewitness accounts and anecdotal information received from a number of people, including city staff members, Ashland Watershed Partnership members, citizens, and affected business owners. While the information obtained tended to fit into a wide range of precision and detail, some common trends did emerge. The scenario is as follows: The Ashland area experienced intermittent, but occasionally heavy, precipitation in the form of rain at lower levels and snow at higher elevations since before Christmas 1996. On the morning of December 31st, the city received a warning from the National Weather Service that heavy rain and a sharp rise in the freezing level was on the way. An emergency meeting of key city staff members was held, and a series of emergency measures were activated, which included the distribution of sandbags. At that time, Ashland Creek was running high, but still within its banks. Localized bank failures were reported in several locations along the creek, and some of the pedestrian bridges in Lithia Park began to be undermined. Generally flow was confined to the creek channel and immediate overbank areas. By late afternoon, some water began running down Winburn Way past the Pioneer Hall and Hillah Temple. A couple of large trees toppled into the creek and were washed downstream until they became entangled in the cantilevered deck in the Calle Guanajuato. By nightfall, other debris had become entrapped and a growing backwater condition was created, which allowed suspended sediment to be deposited in an upstream direction towards the Winburn Way culvert, which was flowing at capacity with some flow bypassing down the west side of the creek channel. Before dawn, the culvert plugged up almost completely, and flow in the creek continued to Ashland Creek Hydraulic Investigation 3 Otak P: \PROJECT\ 7800 \ 7844 \ FLDREPOR\ APPENDC \ASHLAND3. WPD 10.29.97 increase. Significant flow started coming through the Plaza area, past several businesses and city buildings. The majority of this bypassing flow re-entered the creek channel at Bluebird Park, where a deteriorated retaining wall on Water Street gradually collapsed. Some flow continued down Water Street for several blocks. By dawn on New Year's Day, there was substantial flow in the Plaza, Calle Guanajuato, and the creek. Ironically, because of the high amount of split now going through the Plaza, when the flood peaked sometime on New Year's Day, there was considerable channel capacity available in Ashland Creek through the Calle area because so much water had left the channel upstream of the Winburn Way culvert. Significant flow continued through the Plaza area until late in the day on January 2nd, when a bypass channel was completed and the headwall of the culvert was removed where the "Arizona Crossing" was later constructed, and flow gradually returned to the creek channel. The Arizona Crossing and much of the existing culverts were demolished in October 1997, and a 32-foot- wide Con-Span® Bridge was constructed in their place. Approximately a dozen high-water marks were surveyed by the Otak team, and the hydraulic model was calibrated against these marks, taking into account the abnormal conditions caused by the blockage of the Winburn Way culvert. The high- water marks are approximate due to their being influenced by localized variations in geometry and roughness, or by blockage that may not be reflected in the hydraulic model. Since the high-water marks are approximate and the calculation of water surface elevations is also not an exact science, the high-water marks are used in an averaging technique to minimize the amount of error in estimating the peak flow for the January 1997 flood event. Ashland Creek was modeled with the Winburn Way culvert plugged and with all of the other hydraulic structures as they presently exist. The model was run for various flows. The resulting water surface elevations for the different flows were compared to the high-water marks. For each of the flows, the difference between the high-water mark and water surface elevation was summed, and the flow with the summation closest to zero was determined to be the peak flow. The approximate peak flow for the January 1997 flood event was determined to be 2,400 cfs. Figure 4 shows the location of the high-water marks and the water surface profile for a peak flow of 2,400 cfs. Half of the high-water marks are below and half are above the calculated water surface elevation using a flow of 2,400 cfs. A flow of this magnitude correlates to a return period of just below a 25-year flood event based on the Ashland Creek Hydrologic Investigation (Appendix B, Table B-1). Ashland Creek Hydraulic Investigation 4 Otak P:\PROJECT\7800\7844\FLDREPOR\APPENDC\ASHLAND3.WPD 10.29.97 Existing Ashland Creek The reach of Ashland Creek studied for this project has an average gradient of three percent. The three percent slope is a unique feature of Ashland Creek, in that this is a relatively steep slope for a stream through an urban area. Creeks with steep slopes such as the studied portion of Ashland Creek have hydraulic characteristics that, compared to less steep creeks, have relatively shorter backwater curves and water surface elevations that are less responsive to roughness factors. Bed material typically consists of stream cobbles and coarse sand. Channel side slopes generally vary between 1:1 to 2:1 and consist of boulders, grouted areas, and/or vegetation. Channel bottom widths generally range between 10 to 30 feet wide, with a top width between channel banks of 20 to 50 feet. The channel depth (creek invert to top of bank) ranges between 5 and 11 feet, with an average depth of approximately 7 feet. Existing conditions for the purposes of this report are considered to be with the Winburn Way crossing as it was prior to the January 1997 flood event. The Winburn Way crossing presently under construction (Con-Span® Bridge Replacement, October 1997) is discussed in a separate section of this report. Table 1 lists culvert/bridge modeling input parameters for each existing culvert/ bridge, which are shown in an upstream-to-downstream order. Table 1: Existing Culvert/Bridge Parameters Road Crossing Length, Max Low Min Top Station, ft Type & Size f t Chord, o f Road, Elev Elev Winburn Way 99+80 21'x 6' Arch 130 1888.4 1890.2 Culvert* Main Street Bridge 93+60 28'x 9' Arch 75 1874.9 1883 Lithia Way Culvert 90+90 18'x 9' Arch 40 1868.8 1873 Water Street 87+50 Twin 8'x 5' 40 1856.1 1861 Culverts** Van Ness Ave Culvert 81+40 20'x 7.5' Arch 45 1843.1 1845.7 SP Railroad Culvert 80+70 18'x 15.5' Arch 35 1849.9 1857.2 Hersey Street Bridge 75+25 12' x 6.5' Arch 60 1825.8 1827.7 * Outlet portion of Winburn Way is a 13 ft x 7 ft box culvert, 50 feet in length. Extreme skew to the channel axis of flow of 45 ° Ashland Creek Hydraulic Investigation Otak P:\PROJECT\7800\7844\FLDREPOR\APPENDC\ASHLAND3.WPD 10.29.97 Figure 5 shows a profile of the existing water surface elevation compared to the water surface elevation with no hydraulic structures (i.e., bridges or culverts), encroachments, or adjacent buildings. This profile is representative of the "no structures condition." The no structures condition profile was calculated with the HEC-RAS model by removing all hydraulic structures from the model and drawing in the probable water surface elevation in locations where the creek channel has been constricted due to buildup from the urban environment (i.e., narrowing of the creek for hydraulic structures or adjacent buildings). The no structures condition profile is included in this report to illustrate the impact of hydraulic structures and encroachments on the Ashland Creek water surface profile. The overall lateral extent of flooding due to the 100-year design storm event of 3,100 cfs, for existing channel conditions, is indicated in Figure 6. A description of the lateral extent and impacts of flooding is described in the following detailed discussion of individual reaches and hydraulic structures. Each of the existing culverts/bridges and reaches between culverts/bridges was also evaluated using the 100-year design storm event determined by the Otak team. Lower flows were also evaluated to determine typical channel capacity prior to overtopping the bank and also to estimate culvert capacity, just prior to overtopping. For each culvert, a short description of the backwater effects caused by the structures were prepared. Also described is the relationship between surveyed first finished floor elevations and the adjacent 100-year water surface elevation. The existing culverts/bridges and reaches are described in an upstream-to- downstream order. For this narrative, looking downstream is considered to be north and upstream is to the south. The left bank (looking downstream) is considered to be west and the right bank is to the east. Lithia Park Reach This reach is 1,730 feet in length from Butler band shell (upstream limit of the project) to just downstream of the existing Winburn Way culvert. This reach consists of the Winburn Way culvert, four pedestrian bridges (one of which was destroyed in the January 1997 flood event), and two masonry rubble check dams protecting two water mains. Channel capacities in this reach range from 1,200 to more than 2,000 cfs. The largest channel capacity is in the area between the Atkinson Memorial Bridge and the masonry rubble check dams. The existing Winburn Way culvert has a hydraulic capacity of 850 cfs prior to overtopping. At a 100-year design flow of 3,100 cfs, the flow above Winburn Way becomes split, with approximately 700 cfs flowing through the Plaza and 2,400 cfs through Ashland Creek and adjacent overbank areas. The split is due to the amount of flow in the right overbank area and its general topography. The buildings between the Plaza and Calle Guanajuato split the flow, with some flow going down the Plaza and the rest along the Ashland Creek. Winburn Way causes a negligible Ashland Creek Hydraulic Investigation 6 Otak P:\PROJECT\7800\7844\FLDREPOR\APPENDC\ASALAND3.WPD 10.29.97 backwater effect for the 100-year flood event due to the amount of overbank flooding that begins to occur at relatively low flow rates. The 100-year flood at the upstream face of the culvert (cross section 99+90) reaches an elevation of 1892.4 feet. Flooding impacts of the other structures in this reach, as compared to no structure conditions, include: • Atkinson Memorial Bridge at cross section 105+70 has a maximum increase of two feet and a backwater effect that extends upstream 85 feet. • Masonry rubble check dams at cross sections 109+45 and 100+10 cause a combined maximum water surface elevation increase of 2.5 feet and a 140-foot- long backwater effect. • Pedestrian bridge at cross section 111+18 (adjacent to Lithia Park storage building) causes a maximum increase in 100-year water surface elevations of 1.2 feet and a backwater effect of 50 feet. • Pedestrian bridge at cross section 115+10 (upstream of Butler band shell) has a maximum water surface elevation increase of 2.5 feet and a backwater effect of 120 feet. The lateral extent of flooding in this reach ranges between 100 feet at the southern end and 300 feet at the northern end of the reach. There are two locations where flood impacts are due more to overbank flooding from upstream areas than to overbank flooding in the creek area adjacent to the location. These locations are downstream of the northern masonry rubble check dam (cross section 109+45) in the left overbank area and downstream of the Atkinson Memorial Bridge (cross section 105+70) on the left and right overbank areas. Three first finished floor elevations were surveyed in this reach. The Hillah Temple, Pioneer Hall, and the Lithia Park storage building have finished floor elevations of 1893.5, 1899.4, and 1928.9 feet, respectively. Just adjacent to Hillah Temple, the 100-year water surface elevation (cross section 100+35) is at an elevation of 1893.6, which is 0.1 feet above the first finished floor elevation of the building. At Pioneer Hall, the adjacent 100-year water surface elevation (cross section 102+90) of 1899.6 feet is 0.2 feet above the first finished floor elevation. At the storage building located adjacent to a pedestrian bridge (cross section 111+25), the 100-year water surface elevation at 1930.1 is 1.2 feet higher than the first finished floor elevation. Calle Guanajuato Reach The Calle Guanajuato reach is 535 feet long and runs from just downstream of the Winburn Way culvert to the downstream face of Main Street. Hydraulic impacts are from the Main Street Bridge, a pedestrian bridge, cantilevered deck encroachment, and the right bank retaining wall. Main Street Bridge has a capacity of approximately 3,000 cfs prior to any significant overtopping. The bridge has a relative large capacity, in part due to the amount of available head (i.e., the distance Ashland Creek Hydraulic Investigation 7 Otak P:\PROJECT\7800\7844\FLDREPOR\APPENDC\ASHLAND3.WPD 10.29.97 between the maximum crown of the bridge and the minimum overtopping elevation is substantial). The high amount of head causes a relatively high backwater effect, which impacts upstream buildings. Buildings impacted by flooding include the solid block of buildings that line the east side of the Calle. Ten of these buildings have surveyed first finished floor elevations facing the Calle Guanajuato ranging between 1890.3 at Lithia Stationer's (southern end) to 1873.5 at Munchies (northern end). For the existing conditions 100-year design storm event, the flow of Ashland Creek through the Calle Guanajuato reach was analyzed using a flow of 2,400 cfs, due to the upstream flow split. The upstream split is located just upstream of Winburn Way, where approximately 700 cfs flows through the Plaza area on the right overbank and 2,400 cfs continues down Ashland Creek. The majority of the 700 cfs flowing through the Plaza rejoins Ashland Creek just downstream of Main Street at Bluebird Park. With the 100-year design storm event, the backwater effect from the Main Street Bridge extends to a length of 380 feet upstream of the bridge. The maximum backwater increase is five feet at the upstream face of the Main Street Bridge (cross section 94+00), as compared to no hydraulic structure conditions. The Calle Guanajuato Pedestrian Bridge and cantilevered deck located upstream of Main Street cause minor backwater effects. The major impact of the cantilevered deck is its ability to capture and detain debris, such that the blockage due to debris may contribute significantly to the flooding impact. Typical channel capacities within the Calle Guanajuato reach are approximately 1,700 cfs, with the right bank being overtopped at flows ranging between 1,800 cfs and 3,000 cfs (average of 2,400 cfs). Although some right bank elevations adjacent to buildings are high enough to prevent overtopping for a specific flow at that location, they are compromised by relatively lower bank elevations upstream where overtopping occurs. The lateral extent of flooding in the Calle Guanajuato reach is typically 80 feet and is confined by the buildings on the right bank and the steep topography on the left bank. Table 2 on the next page presents surveyed first finished floor elevations compared to adjacent water surface elevations from the 100-year design storm of 2,400 cfs through this reach. Also shown are the right bank elevations for the associated cross sections. As previously mentioned, a bank elevation higher than the water surface elevation will not necessarily protect the associated first finished floor from being flooded if overbank flooding occurs upstream. For example, if Winburn Way is overtopped, there will be water flowing in the Calle Guanajuato regardless of the elevation of the right bank in the Calle reach. Ashland Creek Hydraulic Investigation g Ctak P: \PROJECT\ 7800 \7844 \FLDREPOR\APPENDC\ASHLAND3.WPD 10.29.97 Table 2: Calle Guanajuato 100-Year Water Surface Elevations, Existing Conditions Adjacent Right Bank Finished Water Potential Cross Elevation Floor Surface Flood Name Section Elevation Elevation Depth, feet Lithia Stationers 98+60 1888.8 1890.3 1891.4 +1.1 Pilaf Restaurant 98+20 1887.9 1888.2 1886.8 1.4* Masonic Temple 98+20 1887.9 1887.4 1886.8 0.6* American Trails 97+40 1884.8 1879.0 1883.9 +4.9 Rare Earth 96+45 1882.9 1876.2 1881.7 +5.5 Players Bar 96+45 1882.9 1875.4 1881.7 +6.3 Plaza Cafe 95+90 1878.8 1882.8 1881.3 1.5* The Blacksheep 95+65 1880.4 1880.9 1881.3 +0.4 Greenleaf 95+65 1880.4 1878.6 1881.3 +2.7 Restaurant Munchies 95+38 1880.7 1873.5 1880.6 +7.1 * Height of Freeboard (feet) above 100-year water surface elevation. Flood depths for the 100-year event are up to 7.1 feet deep on the Calle Guanajuato under existing conditions. Bluebird Park Reach The 255-foot reach of Ashland Creek between Lithia Way culvert and the downstream face of the Main Street Bridge is hydraulically impacted by the Lithia Way culvert, two pedestrian bridges, and buildings (two restaurants on the left bank, Thai Pepper to the south and Ashland Creek Bar & Grill to the north, and the 31 Water Street Building on the right bank) adjacent to the creek. The culvert under Lithia Way has a hydraulic capacity of 1,500 cfs prior to overtopping. Flow that overtops the culvert is conveyed through the right overbank area and onto Water Street. The combined effect of the various channel encroachments causes a backwater effect through the Bluebird Park reach. The increase in water surface elevation as compared to a no structure condition ranges between approximately three feet in the upper portion of Bluebird Park (downstream of Main Street) to approximately six feet just upstream of the Lithia Way culvert. The Lithia Way culvert hydraulically impacts the area between the culvert and the pedestrian bridge (cross section 91+72). Between this pedestrian bridge and the Main Street Bridge, the hydraulic impacts are due to the creek constriction from the adjacent buildings. Ashland Creek Hydraulic Investigation 9 Otak P:\PROJECT\7800\7844\FLDREPOR\APPENDC\ASHLAND3.WPD 10.29.97 In the vicinity of the first pedestrian bridge downstream of Main Street, which connects 31 Water Street and the Thai Pepper Restaurant, the 100-year water surface elevation is 1876.4 feet (cross section 92+30). This is significantly higher than the elevation of the patio to which the pedestrian bridge connects at approximately 1873 feet (adjacent to cross section 92+30) and substantially higher than the surveyed finished floor elevation of 1868.2 feet for the 31 Water Street Building (also adjacent to cross section 92+30). The total lateral extent of flooding in this reach is relatively narrow in lateral extent, averaging approximately 60 feet in width, due to the continuing topography and structures. This reach has a channel hydraulic capacity of between 1,000 and 1,600 cfs. The most seriously flood-prone building in this reach is the 31 Water Street Building. The first finished floor elevation of this building is at elevation 1868.2 feet, which is 0.2 feet below the 2- year flood event elevation of 1868.4 feet (950 cfs). Lithia Way Reach to Water Street From the culvert under Lithia Way to Water Street, the 100-year storm event creates both overbank flooding in the right overbank area upstream of the Lithia Way culvert due to the restriction caused by the Water Street culvert and the adjacent overbank topography and structures. The total lateral extent of flooding in this reach ranges between 140 to 180 feet in width. The typical hydraulic capacity of the creek in this reach is 1,500 cfs. Water Street Culvert The existing twin culvert at Water Street has a hydraulic capacity of 700 cfs prior to overtopping. The maximum backwater increase at the upstream face of Water Street as compared to no structure conditions is approximately four feet, which demonstrates that this structure represents a significant barrier to stream flow. The backwater effect from the Water Street twin culvert continues upstream for a distance of 120 feet, with a backwater elevation of 1864.8 feet at cross section 87+60. The backwater effect is high here due to the relative small opening of the culverts, skewness of Water Street with respect to the channel, and the restriction of the overbank areas due to the topography and adjacent buildings, including a new condominium building. The skewness of Water Street (45 degrees) to Ashland Creek causes the effective opening width of the culverts to be decreased to 71 percent of the actual opening. The flooding at this location impacts the new condominiums just upstream of Water Street on the left bank. The first finished floor elevation of the new condominiums (adjacent to cross section 87+60) is at 1864.3 feet. This is 0.5 feet lower than the predicted 100-year elevation of 1864.8 feet at that location. Overtopping flow in the left overbank area flows down Water Street and adjacent areas, including the front of Water Street Inn. Ashland Creek Hydraulic Investigation 10 Ctak P:\PROJECT\7800\7844\FLDREPOR\APPENDC\ASHLAND3.WPD 10.29.97 Water Street to Van Ness Avenue Between the Water Street and Van Ness Avenue culverts, the 100-year flood event causes flooding in both overbank areas with the most extensive flooding occurring in the left overbank area. Flooding in the left overbank area is due in part to the general topography of this specific reach and also from upstream overtopping of Water Street and the resultant flow down the portion of Water Street that parallels Ashland Creek. In the vicinity of Water Street Inn (cross section 86+75), the 100- year water surface elevation computed by the HEC-RAS model is at 1858.9 feet. This is two feet higher than the Water Street Inn first finished floor elevation of 1856.9 feet. Flooding of the front of the building facing Water Street will be due to floodwater leaving the channel upstream of Water Street Bridge and then flowing down Water Street. The "dragon's teeth" just upstream of Van Ness Avenue do not have a significant effect on flood flows due to their relative small blockage of flow as compared to the entire flow area. However the dragon's teeth have the capability of capturing and detaining debris such that they may cause a significant blockage of flow in Ashland Creek. The total lateral extent of flooding within this reach ranges between 140 to 240 feet in width. The average capacity of the creek is 1,500 cfs. Van Ness Avenue Culvert The Van Ness Avenue culvert has a capacity of 1,500 cfs prior to overtopping. The impact of the Van Ness Avenue culvert in combination with the Southern Pacific Railroad (SPRR) culvert causes a maximum backwater elevation increase of six feet at the upstream face of Van Ness Avenue, as compared to no-structure conditions. The backwater effect from the two combined culverts continues for a distance of 270 feet upstream of the SPRR culvert with a backwater elevation of 1849.7 feet at the upstream face of Van Ness (cross section 81+50). Overtopping of Van Ness Avenue occurs on both channel overbanks. Southern Pacific Railroad Culvert The Southern Pacific Railroad (SPRR) culvert is the largest culvert within the portion of Ashland Creek studied for this project and has a capacity greater than the 100-year design storm of 3,100 cfs. Although the SPRR culvert has the largest capacity, the constriction to the sides of the creek from the culvert causes a backwater effect which is further exacerbated by the Van Ness culvert. The SPRR has another large culvert through the railroad embankment for Water Street, located approximately 150 feet west of the SPRR culvert for Ashland Creek. The Water Street culvert provides a conduit for flow overtopping Van Ness Avenue to flow down Water Street and impact the left overbank area downstream of the Southern Pacific Railroad. Ashland Creek Hydraulic Investigation 11 Otak P:\PROJECT\7800\7844\FLDREPOR\APPENDC\ASBIAND3.WPD 10.29.97 Southern Pacific Railroad to Hersey Street Between the Southern Pacific Railroad and Hersey Street, the 100-year flow will cause extensive lateral inundation of the Ashland Christian Fellowship parking lot in the right overbank area. This flooding is due to the low topographic relief in the area. The left overbank area within this reach will also receive floodwaters, due to the upstream overtopping of Van Ness Street and the subsequent flow through a large Southern Pacific Railroad culvert over Water Street. The total lateral extent of flooding in this reach averages about 300 feet in width. The average hydraulic capacity of the creek in this reach is approximately 1,500 cfs. Hersey Street Bridge Hersey Street Bridge has a capacity of 500 cfs prior to overtopping. At a 100-year event design flow, the culvert causes a maximum backwater increase of four feet at the upstream face of the bridge, as compared to no-structure conditions. The backwater effect continues for a length of 120 feet upstream of the bridge with a backwater elevation of 1831.5 feet (cross section 76+75). The backwater is 0.5 feet lower than the surveyed finished floor elevation of 1832.0 feet for Ashland Christian Fellowship (adjacent cross section at 76+75). The church is located approximately 120 feet east of the right bank just upstream of the Hersey Street Bridge. Summary of Ashland Creek Existing Hydraulic Conditions • Appendix C presents a summary of the flooding impacts and channel capacities for the studied portion of Ashland Creek. • Typical hydraulic capacity for Ashland Creek under existing conditions is 1,500 cfs, which corresponds to a 5-year flood event as determined in the Ashland Creek Hydrologic Investigation (ref: Otak, 1997). • Flooding impacts from individual hydraulic structures and encroachments are generally localized due to the relatively steep gradient of Ashland Creek. Notable exceptions to this are the combined effects of the SPRR and Van Ness Avenue culverts and the combined effect of the Lithia Way culvert and the buildings adjacent to the creek at Bluebird Park. • Table C-1 in Appendix C shows surveyed first finished floor elevations, existing 100- year water surface elevations, and the associated flood depths. New Winburn Way Culvert Replacement Structure Post-flood evaluation of the January 1997 flood event has determined that the most significant impacts of the event was property damage from floodwater and the associated sediment and debris deposition in buildings between the Calle Guanajuato and the Plaza. Based on public meetings and discussions between Otak staff and City staff, the initial Ashland Creek restoration program efforts were focused on replacement of the Winburn Way culvert. Primary hydraulic issues for the culvert replacement structure were to decrease blockage potential and increase flow capacity. Otak was directed by the City of Ashland to design the culvert Ashland Creek Hydraulic Investigation 12 Otak P: \PROJECT\ 7800 \ 7844 \FLDREPOR\APPENDC \ASHLAND3.WPD 10.29.97 replacement. Construction plans for this project were submitted to the City in September 1997, and the project is currently under construction, with completion scheduled for late November 1997. The existing culvert will be replaced with a precast bridge structure and floodwall, with sufficient hydraulic capacity to convey the 100-year design storm event (3,100 cfs). The new bridge structure is a 32-foot-wide by 9-foot-high Con-Span® Bridge. The bridge will be 72 feet long, with a gradient of three percent, which matches the natural stream grade. Associated with the culvert replacement is upstream channel widening, a floodwall to prevent significant overflow from flooding into the lower Lithia Park and Plaza area, and the removal of the cantilevered deck downstream of Winburn Way. The height of the floodwall in lower Lithia Park will be 3.5 feet above existing grade. The channel modifications to Ashland Creek above the new Winburn Way Bridge will extend about 100 feet upstream of the upstream face of Winburn Way Bridge. Modifications to Ashland Creek are reflected in the HEC-RAS hydraulic model by modifications in the cross section geometry. Figure 7 shows the 100-year water surface profile with the new Con-Span® Bridge and other modifications compared to the existing water surface profile for the 100-year design storm event. Figure 8 shows a plan view indicating the lateral extent of 100-year flooding due to the new Con-Span® Bridge and associated Ashland Creek channel modifications. Figure 9 shows a plan view of the lateral extent of flooding due to the 25-year design storm event. This figure also includes the influences of the Con-Span® Bridge and associated Ashland Creek channel modifications. Table D-1 (Appendix D) shows the existing and new water surface elevations and other hydraulic parameters for the portion of the reach impacted by the new Con-Span® Bridge. The tables and figures do not reflect any other changes to Ashland Creek except for the modifications to Winburn Way and associated items (i.e., floodwall and creek improvements). The new bridge does not affect the creek north of Main Street or south of the Atkinson Memorial Bridge in Lithia Park. The new Winburn Way Bridge lowers the 100-year floodwater surface elevation upstream of the existing culvert and, along with the floodwall and widened creek geometry, greatly reduces the probability of flooding in the Plaza area. The larger hydraulic capacity of the new bridge will lower the water surface elevation at cross section 100+35 (adjacent to Hillah Temple) to an elevation of 1892.1, which is 1.4 feet lower than the surveyed first finished floor elevation of 1893.5 feet. Other benefits besides preventing flow from entering the Plaza area for the new culvert replacement structure and floodwall include: Overtopping of Winburn Way at Ashland Creek is protected up to the 100-year design storm event. Ashland Creek Hydraulic Investigation 13 Otak P:\PROJECT\7800\7844\FLDREPOR\APPENDC\ASHLAND3.WPD 10.29.97 • Lower probability of left overbank flooding into the portion of Winburn Way that is parallel to Ashland Creek upstream of the culvert replacement structure. • Lower probability of right overbank flooding into the lower Lithia Park area. Due to the floodwall's ability to contain the right overbank flow, most of the 100-year flow event is contained within the creek and left overbank area in the vicinity of the new bridge. As presently designed, a tie-in to high ground has not been included in the floodwall at the request of the Ashland Parks and Recreation Department. The wall ends at the existing pedestrian pathway near the lower duck pond in Lithia Park. Under 100-year flood conditions, approximately 50 to 100 cfs could flow through this gap at the end of the wall. Parks Department staff believe that they will be able to plug this gap with sandbags, thereby completing the line of protection in case of a 100-year flood event. At the present time, it is not known if FEMA (Federal Emergency Management Agency) will certify the floodwall and Winburn Way Con-Span® Bridge as providing 100-year protection for the Plaza. This is in part due to the gap (no solid tie-in to high ground). FEMA has in the past has been known to certify such structures if there is documented evidence of a flood-fighting plan for gap areas. The Winburn Way modifications will increase the amount of flow in the Calle Guanajuato reach of the creek during the 100-year event from 2,400 cfs to 3,100 cfs. The impact to this reach without other improvements will be an increase in water surface elevation ranging between one to two feet within the Calle Guanajuato reach. Improvements to Ashland Creek for potential reduction of this impact are discussed in later sections of this report. In summary, the Winburn Way culvert replacement structure and associated floodwall reduces water surface elevations upstream of Winburn Way and serves to prevent significant flow from entering the Plaza area. It also increases flow through the Calle Guanajuato reach, which increases 100-year water surface elevation above what is experienced currently. Without the floodwall, the Winburn Way Bridge has a flow capacity during the 100- year storm event of 2,300 cfs. It is estimated that approximately 300 cfs of the overbank flow will occur in the right overbank, with the possibility of flooding the Plaza area. Figure 10 shows the water surface profile without the floodwall, and Table D-2 shows the existing and proposed water surface elevation and other hydraulic parameters for these conditions. Ashland Creek Hydraulic Investigation 14 Otak P:\PROJECT\7800\7844\FLDREPOR\APPENDC\ASHLAND3.WPD 10.29.97 Ashland Creek Restoration Priorities The major culverts/bridges on Ashland Creek and stream channel reaches are listed in Table 3, on the next page, in upstream-to-downstream order. The table lists the known properties and areas impacted by flooding due to each existing culvert/bridge and creek reach. These properties are listed in the Table 3 matrix and differentiated into separate columns depending upon the type of structure (habitable or nonhabitable) and depth of flooding during the 100-year flood event. Each column has been assigned a relative priority, with higher values given to columns with higher potential economic loss from flooding. The score column indicates the total score for each culvertibridge and reach, with higher numbers representing a higher potential economic loss from flooding. For example, the properties and areas impacted by flooding from Van Ness culvert include Van Ness Avenue and Water Street (assigned weighting value of two for each location), the recycle center with an assigned value of three, and a house and garage (assigned value of three). The total relative score for Van Ness culvert was calculated to be ten (2x2+1x3+1x3 = 10). The far right column is the rank number and it ranks the various structures and reaches in terms of relative flood damage reduction. This prioritization table is included in the report to give a relative sense of flood economic impacts associated with from each culvert/bridge and reach. It is a deterministic prioritization of potential future improvements to Ashland Creek, with the ranking system based on relative economic benefits, in terms of flood loss reduction associated with improving the hydraulic capacity at each listed location. Culverts/bridges and stream channel reaches with high scores and with significant flood impacts to habitable structures were designated for further evaluation. Hersey Street Bridge was also chosen for further evaluation due to its limited hydraulic capacity. The proposed improvements to be evaluated are listed below by priority. These improvements do not include the Winburn Way culvert replacement culvert since this is currently under construction. * Main Street and Calle Guanajuato Reach - This area has the highest priority due to the impacts of flooding on the entire row of buildings between the Plaza and Calle Guanajuato. Also, this area will be negatively impacted by the Winburn Way culvert replacement structure, because more flow and associated higher water surface elevations will occur in this reach of the creek during the 100-year storm event once the culvert replacement project is complete. Lithia Way Culvert and Bluebird Park Reach - This area was chosen for potential future improvements due to backwater effects from the culvert and adjacent buildings impacting the flooding of the Bluebird Park area. Ashland Creek Hydraulic Investigation 15 Otak P:\PROJECT\7800\7844\FLDREPOR\APPENDC\ASHLAND3.WPD 10.29.97 Ashland Creek Restoration Priorities The major culverts/bridges on Ashland Creek and stream channel reaches are listed in Table 3, on the next page, in upstream-to-downstream order. The table lists the known properties and areas impacted by flooding due to each existing culvert/bridge and creek reach. These properties are listed in the Table 3 matrix and differentiated into separate columns depending upon the type of structure (habitable or nonhabitable) and depth of flooding during the 100-year flood event. Each column has been assigned a relative priority, with higher values given to columns with higher potential economic loss from flooding. The score column indicates the total score for each culvert/bridge and reach, with higher numbers representing a higher potential economic loss from flooding. For example, the properties and areas impacted by flooding from Van Ness culvert include Van Ness Avenue and Water Street (assigned weighting value of two for each location), the recycle center with an assigned value of three, and a house and garage (assigned value of three). The total relative score for Van Ness culvert was calculated to be ten (2x2+1x3+1x3 = 10). The far right column is the rank number and it ranks the various structures and reaches in terms of relative flood damage reduction. This prioritization table is included in the report to give a relative sense of flood economic impacts associated with from each culvert/bridge and reach. It is a deterministic prioritization of potential future improvements to Ashland Creek, with the ranking system based on relative economic benefits, in terms of flood loss reduction associated with improving the hydraulic capacity at each listed location. Culvertsibridges and stream channel reaches with high scores and with significant flood impacts to habitable structures were designated for further evaluation. Hersey Street Bridge was also chosen for further evaluation due to its limited hydraulic capacity. The proposed improvements to be evaluated are listed below by priority. These improvements do not include the Winburn Way culvert replacement culvert since this is currently under construction. • Main Street and Calle Guanajuato Reach - This area has the highest priority due to the impacts of flooding on the entire row of buildings between the Plaza and Calle Guanajuato. Also, this area will be negatively impacted by the Winburn Way culvert replacement structure, because more flow and associated higher water surface elevations will occur in this reach of the creek during the 100-year storm event once the culvert replacement project is complete. • Lithia Way Culvert and Bluebird Park Reach - This area was chosen for potential future improvements due to backwater effects from the culvert and adjacent buildings impacting the flooding of the Bluebird Park area. Ashland Creek Hydraulic Investigation 15 Otak P:\PROJECT\7800\7844\FLDREPOR\APPENDC\ASHLAND3.WPD 10.29.97 Table 3. Priority Matrix for CulvertslBridges and Reaches Structure Road/Park Nonhab. Habitable Building Bldg Flood Depth, > 0 ft > 1 ft +l- 1 ft > 1 ft Score Rank Assigned 2 3 3 5 Value Lithia Park 2 -Winburn 2 -Band shell 2 -Lithia Cafe & 16 5 Reach Way & Park & Storage Pioneer bldg Winburn Way 3 -park, Plaza, 12 -Hillah, 10 42 1 Culvert Winburn Way bldgs (Plaza side), Comm bldg Calle Reach 2 -bldgs in Calle 6 -bldgs in 36 2 and Main Calle Street Bridge Main Street 1-bldg in Calle 5 -bldgs in 28 3 Bridge Calle Bluebird Park 3 -two rest. & 15 6 Reach 31 Water St Lithia Way 1 -Water St 3 -two rest. & 17 4 Culvert 31 Water St Lithia Way to 1-Restaurant 3 10 Water Street Reach Water Street 1 -Water St 1 -Commercial 1-new Condo. 1 -Water St 13 7 Culverts prop Inn Water Street 1-Water St 5 9 to Van Ness Inn Reach Van Ness 2 -Van Ness & 1 -Recycle 1 -House & 10 8 Culvert Water St Center Garage SPRR to 1-Church 3 10 Hersey Street Reach Hersey Street 1-Hersey St 1-Church 5 9 Bridge Assigned value based on relative economic impact of potential flood damage at the location listed. Does not include flow capacity since bridges/ culverts that have a high capacity due to high available head may contribute to high backwater effects. Ashland Creek Hydraulic Inuestigation 16 Otak P:\PROJECT\7800\7844\FLDREPOR\APPENDC\ASHLAND3.WPD 10.29.97 • Water Street Twin Culverts - The Water Street twin culverts are candidates for future improvement due to the low hydraulic conveyance capacity of the existing structure and associated flooding impacts caused by floodwater overflowing Water Street upstream and downstream of the twin culverts. • Hersey Street Bridge - This bridge is in need of replacement due to its extremely limited hydraulic capacity. Other areas were not considered for possible improvements due to the relatively minor impact of flooding or the impracticality of replacing a structure or widening the creek for a relative minor amount of flood damage reduction. The priority projects listed above are based on a subjective, but nonetheless deterministic, ranking system. Potential Ashland Creek Improvements Calle Guanajuato Reach The conceptual improvement to the Calle Guanajuato reach includes widening the creek by ten feet on the left bank (looking downstream) and constructing a low floodwall on the right bank. The wider channel width would be designed, taking into account environmental and aesthetic concerns. This improvement would be required through the entire Calle Guanajuato reach. The floodwall would be located on the west edge of the Calle Guanajuato and would range from 1 to 3.5 feet in height, with an average of two feet above the existing street grade. The freeboard on the proposed floodwall ranges between 0.6 feet and 3.0 feet, with an average freeboard of 1.5 feet. At the extreme lower end of the Calle Guanajuato, a seven-foot-high floodwall would be necessary due to the low street elevation at this point (low point of approximately 1875 feet) and to contain the backwater from the Main Street Bridge. At this end (north) of the Calle Guanajuato, the lower buildings would be flooded due to backwater from Main Street if the higher floodwall were not constructed. With a proposed 100-year water surface elevation of 1881.9 at cross section 95+38 where the lower retaining wall begins, the following businesses would have first finished floor elevations below the Main Street Bridge backwater elevation: Munchies (finished floor elevation of 1873.5 feet), Greenleaf Restaurant (elevation of 1878.6 feet), The Blacksheep (elevation of 1880.9 feet), and Players Bar (elevation of 1875.4 feet), Rare Earth (elevation of 1876.2 feet), and American Trails (elevation of 1879.0 feet). The floodwall could be a permanent or a temporary structure (to be put in place in the fall and removed the following spring). It is noted that the City of Portland has recently added a structure of this type along the downtown sea wall. An example of a temporary structure would be reinforced concrete sections placed into slotted concrete posts. The concrete panels could be put in storage during the summer. Ashland Creek Hydraulic Investigation 17 Otak P:\PROJECP\7800\7844\FLDREPOR\APPENDC\ASHI.AND3.WPD 10.29.97 Included with this improvement would be a proposed replacement pedestrian bridge to span the wider creek. It is recommended that the existing creek banks in the Calle Guanajuato be restored in locations where the gunite bank protection is failing. The hydraulic model was modified to incorporate Calle Guanajuato reach improvements and was evaluated with the new Con-Span® Bridge in Winburn Way. Figure 11 indicates the water surface profile comparison between the existing conditions and modifications (i.e., enlarged creek channel cross section, floodwall, longer pedestrian bridge, and the new Winburn Way Con-Spang Bridge). It is noted that the existing conditions include the previous Winburn Way culvert in place as it was before the January 1997 flood event. Figure 12 is a plan view showing the lateral extent of flooding with the proposed improvements in place. Table D-3 shows the proposed water surface elevations and associated hydraulic parameters of the Calle Guanajuato improvements with the new Winburn Way Bridge versus existing conditions. The proposed improvements to Calle Guanajuato do not affect the creek downstream of Main Street or upstream of Winburn Way. The proposed Calle Guanajuato modifications (widening of the creek and floodwall) will lower the 100-year flood event water surface elevation by an average of 0.9 feet between Winburn Way and the location of the existing pedestrian bridge, as compared to existing conditions. Between the existing pedestrian bridge and Main Street, the change in water surface elevation is typically increased by 1.2 feet due to the increased amount of flow passing through the new Winburn Way Bridge. Lithia Way Culvert and Bluebird Park Reach The high water surface elevations in the Bluebird Park vicinity between the Lithia Way culvert and Main Street are mainly to the culvert under Lithia Way and the restriction of the creek caused by the existing restaurants and the 31 Water Street building. The recommended improvement to Bluebird Park is to replace the 18-foot- wide by 9-foot-high Lithia Way culvert with a 30-foot-wide by 10-foot-high arch culvert. Other recommended improvements include widening the creek channel upstream and downstream of the culvert to maintain the efficiency of the larger culvert. Removal of the 31 Water Street building was also studied in the model but is not considered an option at this time. The hydraulic model was modified to reflect these proposed improvements. Modifications to the Bluebird Park reach have no effect on the water surface elevation downstream of the Lithia Way culvert or upstream of Main Street. These proposed improvements will affect the right overbank flow downstream of Lithia Way culvert, with less overbank flow occurring due to the increased hydraulic capacity of the larger culvert. Figure 13 indicates the water surface profile with the conceptual improvements compared to the existing conditions water surface profile. Ashland Creek Hydraulic Investigation 18 Otak P:\PROJECP\7800\7844\FLDREPOR\APPENDC\ASHLAND3.WPD 10.29.97 Also, a plan view (see Figure 12) is shown indicating the lateral extent of flooding due to the improvements. It can be readily seen that the lateral extent of flooding with these proposed improvements does not change significantly (except for the location of the 31 Water Street building) as compared to reductions in 100-year water surface elevations that are achieved by the proposed improvements. Table D- 4 (located in Appendix D) shows the hydraulic parameters of the proposed Bluebird Park improvements as compared with the existing channel conditions. When compared to existing channel conditions, the proposed Bluebird Park modifications would lower the 100-year floodwater surface elevation by an average of 3 feet between Lithia Way culvert and Main Street. A typical 100-year water surface elevation in this reach is 1872.5 feet at cross section 92+30. The proposed improvements would bring the 100-year water surface elevation 0.5 feet below the top of the high patio at elevation 1873 feet (cross section 92+30) at the Thai Pepper Restaurant just downstream from Main Street, but still significantly higher than the first finished floor elevation of the 31 Water Street building (removed for hydraulic calculations) at 1868.2 feet. In summary, the increase in the proposed Lithia Way culvert hydraulic capacity to 2,800 cfs will lower the 100-year water surface elevation between the culvert and 31 Water Street building by an average of three feet, while the removal of the building would lower the water surface elevation between the 31 Water Street building and Main Street Bridge also by an average of three feet. The proposed modifications to Lithia Way culvert and the Bluebird Park reach will also affect the existing conditions flood impacts of this reach (see Table 3) by reducing the amount of overtopping flow to the portion of Water Street downstream of Lithia Way culvert by approximately two-thirds, and by reducing flood levels adjacent to the two Bluebird Park restaurants. With these improvements in place, the 100-year water surface elevation at the Ashland Creek Bar & Grill (cross section 91+68) is reduced from 1876.2 feet to 1872.4 feet (3.8-foot reduction) and at the Thai Pepper Restaurant (cross section 92+30), the level is reduced from 1876.4 feet to 1872.5 feet (3.9-foot reduction). Water Street Culvert The backwater created by the Water Street twin culverts, overbank topography, and adjacent buildings, causes significant flow over Water Street, impacting the adjacent buildings and the portion of Water Street downstream of the culvert and parallel to the creek. The existing culvert is a twin 8-foot by 5-foot culvert, with a hydraulic capacity of 700 cfs prior to overtopping. The conceptual improvement to the Water Street culvert is to enlarge the culvert to a 42 feet by 7 feet arch culvert (effective width of 30 feet due to skew angle) and widen the creek downstream to maintain the efficiency of the larger culvert. Ashland Creek Hydraulic Investigation 19 Otak P:\PROJECP\7800\7844\FLDREPOR\APPENDC\ASHLAND3.WPD 10.29.97 The HEC-RAS model was modified to reflect these proposed improvements. The recommended modifications to the Water Street culvert reduce existing water surface elevations upstream of Water Street for a distance of 160 feet. Figure 14 indicates the water surface profile with the conceptual improvements in comparison to the existing water surface profile. Also, a plan view (see Figure 12) is shown indicating the lateral extent of flooding due to the improvements. Table D-5 (in Appendix D) shows the proposed water surface elevations and other hydraulic parameters of the proposed Water Street improvements as compared with existing conditions. Compared to existing conditions, the proposed Water Street improvements reduce the 100-year floodwater surface from an existing level of 1864.8 feet to 1863.6 feet (1.2-foot difference) at the upstream face of the Water Street culvert (cross section 87+60). The proposed improvements would lower the flood impacts on the new condominiums which have a first finished floor elevation of 1864.3 (also at cross section 87+60). The amount of flow through the proposed culvert for the 100-year flow event is 2,000 cfs instead of the existing culvert capacity of 700 cfs. This will reduce flow overtopping and running down Water Street and reduce flooding impacts to the adjacent roads, the street side of Water Street Inn, and the commercial property on the right bank of the creek. Hersey Street Bridge Hersey Street Bridge has the least amount of hydraulic capacity (500 cfs) in comparison with all of the culverts/bridges within the studied reach from Butler band shell to Hersey Street. The major impact of backwater flooding from the 100- year storm event for the 12-foot by 6.5-foot arched structure is the overtopping of Hersey Street, the flooding of the Ashland Christian Fellowship parking lot, and the proximity of the flooding to the Church. The conceptual improvement for the Hersey Street Bridge is to enlarge the bridge to a 28-foot by 9.5-foot arched hydraulic structure and to widen the creek up and downstream to maintain the efficiency of the larger opening. The hydraulic model was modified to reflect these proposed improvements. The recommended modifications to the Hersey Street Bridge reduce existing water surface elevation upstream of the structure for a distance of 120 feet. Figure 15 indicates the water surface profile with the conceptual improvements in comparison to the existing water surface profile. Also a plan view (see Figure 12) is shown indicating the lateral extent of flooding due to the improvements. Table D-6 (in Appendix D) shows the proposed water surface elevations and other hydraulic parameters of the proposed Hersey Street improvements as compared with existing conditions. Ashland Creek Hydraulic Investigation 20 Otak P: \PROJECT\ 7800 \ 7844 \FLDREPOR\APPENDC \ASHLAND3.WPD 10.29.97 Compared to existing conditions, the proposed Hersey Street improvements reduces the 100-year floodwater surface from an existing elevation of 1831.1 feet to 1829.7 feet (1.4-foot reduction) at the upstream face of the Hersey Street Bridge (cross section 75+55). At cross section 76+75 adjacent to Ashland Christian Fellowship, the existing 100-year flood elevation is at 1831.5 feet, which is 0.5 feet lower than the first finished floor elevation of the church (elevation 1832.0 feet). The proposed improvements at Hersey Street have the same 100-year water surface elevation of 1831.5 feet. Summary ■ The typical existing and proposed hydraulic capacity of Ashland Creek for the project reach is 1,500 cfs; however, the capacity at specific cross sections fluctuates considerably, generally between 1,000 and 2,500 cfs. ■ Generally, the backwater effects from existing structures and reduction of water surface elevations from specific suggested improvements are independent of other structures and improvements due to the relatively steep slope of Ashland Creek. ■ Figure 12 presents a plan view of the entire study reach (Butler band shell to Hersey Street) with all of the proposed improvements (i.e., concrete dam removal, Winburn Way Crossing, Calle Guanajuato, Bluebird Park, Lithia Way culvert, Water Street culverts, and Hersey Street Bridge), and Figure 16 shows a profile view of the entire reach comparing the proposed improvements and existing water surface elevations. Table D-7 (Appendix D) is a table of proposed and existing water surface elevations and other hydraulic parameters for the entire reach. ■ Figure 17 (back pocket of report) is a relative large plan view of the proposed improvements and the associated flood boundary. It is similar to Figure 12, except larger and with the cross sections shown. ■ Table C-2 (Appendix C) lists all of the known properties affected by 100-year flooding, pertinent property elevations, adjacent cross section locations, and the existing and proposed (with improvements) water surface elevations. ■ Modifications were modeled for several culverts (Winburn Way, Lithia Way, Water Street, and Hersey Street) and for a few reaches (upstream of Winbum Way, Calle Guanajuato, and Bluebird Park). ■ The proposed modifications produced lower 100-year water surface elevations and reduced the level and probability of flood impacts to adjacent properties and roads. The exception is the Winburn Way improvement which, without Calle Guanajuato improvements, raises water surface elevations in the Calle Guanajuato reach. ■ The complete HEC-RAS input file for existing conditions and for both of the proposed conditions (Winburn Way Improvement only and All Improvements) is attached in Appendix E. Ashland Creek Hydraulic Investigation 21 Otak P:%PROJECT%7800\7844\FLDREPOR\APPENDC\ASHLAND3.WPD 10.29.97 ■ Summaries for specific improvements to each modified culvert/bridge and reach are as follows: New Hydraulic Improvements: Winburn Way Bridge • Increase existing hydraulic capacity with a new 32-foot-wide by 9-foot-high arch bridge. This will increase the capacity to 3,100 cfs (100-year flood event) and lessen the probability of debris blockage. • Associated modifications with the replacement bridge include an upstream floodwall, channel widening upstream, and the removal of the cantilevered deck. • The typical decrease in water surface elevation compared to existing conditions is 1.5 feet. Water surface elevations would be reduced from the upstream face of Winburn Way to 120 feet upstream of Winburn Way. • One of the main benefits of the new Winburn Way Bridge is the prevention of flow from entering the Plaza. Proposed Hydraulic Improvements: Calle Guanajuato Reach • The Calle is modified by widening the creek by ten feet on the left bank and constructing a flood wall on the right bank. • In comparison with existing conditions, the proposed modifications (includes effects of new Winburn Way Bridge) will typically increase water surface elevations by 1.2 feet in the northern half of the Calle reach. • The floodwall on the right bank will serve to protect Calle businesses from being flooded during a 100-year storm event. • Included with these modifications would be the repair of failing gunite banks and a proposed longer pedestrian bridge. Lithia Way Culvert and Bluebird Park • Increase existing hydraulic capacity with a proposed 30-foot-wide by 10-foot- high arched hydraulic structure. This will increase the hydraulic capacity to 2,800 cfs, which is between a 50- and 100-year flood event. • Associated modifications include widening the creek in the right bank area, a longer pedestrian bridge to the Ashland Creek Bar and Grill, and a longer paved drive below Lithia Way culvert to accommodate the wider Lithia Way culvert. • Other modifications modeled for the reach include the removal of 31 Water Street and the pedestrian bridge between 31 Water Street and the Thai Pepper Restaurant. Ashland Creek Hydraulic Investigation 22 Otak P:\PROJECT\7800\7844\FLDREPOR\APPENDC\ASHLAND3.WPD 10.29.97 • These modifications would typically lower the 100-year water surface elevation throughout the Bluebird Park reach by three feet as compared to existing conditions. • The modifications in this reach would lower flood impacts to Bluebird Park and lower the amount of flow bypassing the Lithia Way culvert during flooding events. • With 31 Water Street left in place, the water surface elevations between Main Street Bridge and Water Street would remain similar to existing condition water surface elevations. Water Street • Increase existing hydraulic capacity with a proposed 42-foot-wide by 7-foot- high arched hydraulic structure. This will increase the hydraulic capacity to 2,000 cfs, which is between a 10- and 25-year flood event. • The maximum decrease of water surface elevation would be 1.7 feet at the upstream face of Water Street. Water surface elevations would be reduced for a distance of 160 feet upstream of Water Street. • The proposed structure will reduce overtopping flows and lessen flood impacts to adjacent roads and properties. Hersey Street • Increase existing hydraulic capacity with a proposed 28-foot-wide by 9.5-foot- high arched hydraulic structure. This will increase the hydraulic capacity to 1750 cfs, which is between a 5- and 10-year flood event. • The maximum decrease of water surface elevation would be 1.4 feet at the upstream face of Hersey Street. Water surface elevations would be reduced for a distance of 120 feet upstream of Hersey Street. • The proposed structure will reduce overtopping flows and lessen flood impacts to adjacent roads and properties. Dragon's Teeth • Removal of dragon's teeth (located above Van Ness Avenue) does not significantly reduce water surface elevations, but it does reduce the potential of debris blockage and associated backwater effects. Concrete Rubble Dams • Removal of two concrete rubble dams and realignment of the water main profiles would lower water surface elevations in the vicinity of these two structures. • In the vicinity of the dams, water surface elevations would be reduced from 0 to 2.5 feet for a distance of approximately 140 feet. • The removal of these dams would increase the hydraulic capacity of the creek in this vicinity and also lower the amount of flow conveyed in the overbank areas. Ashland Creek Hydraulic Investigation 23 Otak P:%PROJECf\7800\7844\FLDREPOR\APPENDC\ASHLAND3.WPD 10.29.97 dVA V38Y 133PO8d 4 38nou m o o = i8Od3d onnv8aH • o soaroad Nouvaossazi QooZa xiazio QMVgHSV 4 i LAJ C9 . V> W - - f (n m cr, z h > r LAS F- LL- W Cn:~ © cr- Z.~v~ /y L m Q LLJ LLJ J M Y ^-v/ z m % LL5 Y LL- w i-- 1 r 1 j W N 1 i \ Lij _cz~ z I~ o m c/7 is + ? - O o - FF, o W w o j w~ i s3oai8e/s.iH3n-lno V soNimine io NoLmoi 2 Mnow a "s o= l8od38 onndeaH • o Q ZoaroHd NOIIVZIOIS51ZI QOOld X21MIo (INV IHSV y ryr~`` ~1 v ~ f CL l/ r LAJ CDn tom i to 0 \ ~O\O p CD- I r \ rv V 1 Q. C W rte, / n\\ / C d .2 :E Ljj i 75 J O 'Lj W . a UZ- `a7~ E I J 'En tcV E,• i' I i j 0 :3 EL z m i 1r .~J Quj \ .i i \ ( I' La - ~i~?HPt i{Gr_C 11 i• i~~ ~ i i. / ~ I i i i , i Y t i Q1 ~ ~ I W w C7 O m ¢ S Ir O 11 -aLOr ` rc I, v 1 W I (n \ U f LLJ cr, 1 I il; b SNOU03S-sS080 30 NOLIVOOl :C 38now s o= i210d38 onnvdaH • o ,Loaro?3a Nouvaossazi Qooza xmizio (INV IHSV C~ W wWuj /?r W C I y V Z-,UJ , ~~^J cr- >-`7 3:: > m W Z Q ML ".N:ANl W % i - 1 co \ Z - % sC` W^ _ k L'Lj LLJ .-d- m Y r i - y, 0 - m ` e I / 0) i - LLJ a 1.5 v i w r r LJJ r4YY Sr,~ 0 Z ' Q Z v I \ p r, CL v l I 1 1 r, v Figure 4: Ashland Creek Water Surface Profile, Flood Event (2,400 cfs) Ashland Creek 1960,,1..._ Legend 1 WS 2400 cfs 1940 • Ground 0 obs ws 2aoo cfs 1920- i 1900, ~I 1880 i....... '1 I _ . > o m I I ~ 1860 1840 ' l i ~ ~ I I 1 ~ ~ 1820 1 Om a LO CO UI) LO m LO 00 Ln LO O v O Ln LO Ln O O m O CO O cm, a> V: C7 Ln OR N W N CD N r` v, r Cn O r` v V). rl~ O m n m N 'I. LO CD r` CA O T T Cn to CO CO O CO Cn C0 00 0 N Cn CD d0 OI O O O O O O O r` r` n 00 00 00 CO CO CO O Of QI O 00) 0I (m r 0 1000 2000 3000 4000 5000 Main Channel Distance (ft) Figure 5: Ashland Creek 100-Year Water Surface Profile, Existing vs. No Hydraulic Structures Conditions Ashland Creek L"md ♦ WS 100 year • Ex Cond 100 WS 100 yew, No Strut 100 Ground 1880 1860 c o I I I w ! I_........ . 1840J' 1820 I j I cn to O LO O rn to 1A to LO N m, 00 O 0 1fl o 0 a Ln L" O CI N n v o I. v rn r.'7 o ao I` rn v v 7 r 1n N NIP n co m o n v U) CO IP CO a) 0 N llI ui CO r CO CA 0 0 N co) CO v to CO h n I~ n n n n n 00w m co ao ;S6 m ao do ao 0 -.do rn rn rn rn rn rn rn rn rn 1800 ~ i ' , r-' r' ~~i , , i ~ , 4 ~ , 0 500 100 1500 2000 Main Channel Distance (ft) Ashland Creek L d WS 100 year - Ex cord 100 WS 100 year. No Struc 100 1940 Ground 1920 I 1900 > I Lu ~ ~ I I ' I l l 1880 { I i I j ' I I LO O O O 1A o O I I i ~ I CO LO CO O LO O O O CD to to O O CO C) - C) _ 7I _ CO O 0O iIq N ~ r ! 1860 rn m n_ ow n_ rn._... O r C! C'7 O I~ O: O O N IT LO CO n n O a) m O M vJ to CO v 1n c6 n r'. o am 0 0 0 0 0 0 0 0 0 0 0 C) C) C) (m Q) C) Q) : rn 2000 2500 3000 3500 4000 Main Channel Distance (ft) SNOLLIGNOO ONLLSDC3 ',kNY(]NnOG (]001W Wlk-OO L N33W ONd1HSd :9 32 nou a iWd321 orindWAH , • 4 sOaroZIa NoISWHOISM Qoozd XEMID QNVIHSV w W W R~ N 0 uj CD W~ =m W Q _ o O O U- Q 0 O v s 3 L O L U Q) F- U- W w C O > v m U Q U-1 3 W cii ~ Z z Q .J ~ ~ Q U ~ W wz Q w~ J _v U v a U w Cn 3 v N v O v o ~ CU 0 0 M LLI O Q~ n 3 z c.D ~m m F-r- m~ z Q) NE: r V) c v m V) ? O co =2 m Q g D Figure 7: Winburn Way only 100-Year Water Surface Profile with Floodwall, Existing vs. New Conditions Ashland Creek WS 100 year . Ex Cond 100 WS 100 year - W VV 1900 Ground Right Levee 1890. _ E 1880.1, LU I I 1870 i 1860 O 00 O to 0 In O (m O 7 Ln _v_rn Na m (9 a C! 0) oonr 17in o ro w c° +1 _rn 1 a m $ 0 0 0 0 0 rn rn rn rn co rn 17 a) 0 0 Q) O 0 0) 1800 2000 2200 2400 2600 2800 3000 Main Channel Distance (ft) AINO S1N3VGAONdW1 JIVM kNnGNIM 4,kNvONnoe 000-U NV3J1-5Z N33NO ONVIHSV :6 32 now idOd3d onnv8aH • 4 loarMld MOIIVHOISMI Qoozd x2122iD GMVIHSV W W W C~ N 2 Of m N W Q 2 m I Ll N wQ Lf7 N CL C L cn N 3 L U N H Li J cn U Q m I- Q W ~ W ~ W W Z J Z Q J U ~ w WZ Q w~ J U F-- W W v V) v E cr- v N _v O C Q ~ O Z U Q Q U ~ ~ O n- p D Z V) Q Q O O O J J L (n C v m Z J W a> _ N m Z O m Q W 0 0 M O N N n O AINO S1N3YGAONdYrl AVM NNneNIM `ANVQNnO8 QOOId 21V3A-OO L >a3W QNVIHSV :8 32 now o s 0 iNOd38 onnv8CIAH 132[rozia NOEWHOISMI Qoozd MEDID (INN IHsv ' W _ W N~ 0 °o Q =m J v LL- vi {Q r O O C d v_ s v U ~ F- V- L v O J cn ~ U m cn w 3 W z w im V) V) F- C) V) °o Q ~ z C2 ~ CD cr- Q U ~,Qw W }I- CD ZZ O W > O O D Z Q J U F- W W L E F- 3 v N v a. o O o V) o v i w LLJ cU- o 3~ YJ n" ¢o C-) Ckf Z O ¢ ¢ V ~ ~ a 3 I Z ¢ p o O F- J LJ J Z W 9 O C r- F- LLJ (n Z C v m Z J W O C7 N E 2 m Z o m M W o M 0 M ~^k L__1 O N in n 0 Kim= 6mmi Sig Kma smoi ftrwmo- &0" 60-do ft~ W---w ft--" -.00 Figure 10: Winburn Way only 100-Year Water Surface Profile without Floodwall, Existing vs. Proposed Conditions Ashland Creek d 19001 _ _ _ _ ws lao year;ww nolwaN w5 100 year • Ez Cond 100 a Ground ~ _ 1890 I I 1880 3i I 0 U w 1870 I 1860 t _ _ _..I _ LnL.Q o ol.... n o 'n 1n o o CO rn LO 0 1n 00 rn m o M r` (n rn < rn i, N m n Mm M n o U - N M ri IT ui U) <c cc r 1., r: g do ai g g o 0 0 0 C1 0 Cl 0 Cl 0 ! Cl Cl 0) 0) Q CJ C1 2000 2200 2400 2600 2800 Main Channel Distance (ft) Figure 11: Calle Guanajuato 100-Year Water Surface Profile, Existing vs. Proposed Ashland Creek 1 Ws 100 y- - Ex Caw 100 J W9100 ywr-P'Com 100E I ~ G1wnC 1890 a n a 1880 ' i _CD U1 18701 laso I . m ~ ~ I N 05 O CO 0 O~ N O N O OI Cu Ni O_ N 7 M ~ N C + cO+ + + T + + 1+ + + C_ O O c i ° v N N N m co In r r~ m m rn rn o 0 rn ~ rn rn o1 rn a1 rn o rn rn rn rn rn rn 3 2000 2200 2400 2600 Main Channel Distance (ft) SLN3W3AOMdV4l TIV 'A8VCINnoe aoo-u HY3Jl-oo l x338o 4NVlHsv Z l WOW O 2 180d3b onmJCI1H a °u 3 0 saHroZIa NOUMIOISMI aoozd XaaZID QNVIHSV - W W CW7 } m W = m O O vi J L.L. WQ r I O O C Al. v c N 3 O ~ U w Li C W o J Cl) V ¢ m } F- Q w 3 w P-tf ¢ cn Z J Z Q J e- Q W WZ a O O Z U J 0 E L~ ~ I-- o w w cn I d O C O C) Q v z W 3 dv o ~ W Q o O Q o cn o F- >-w -jLw YJ LA- Q) CL ¢W O ~ Q 0 r ~ ZN [L 00- (D Z W D C v F- LLJ m z ¢ o¢~ V) m :z m Q w °o M D O N h n O k Figure 13: Bluebird Park Reach 100-Year Water Surface Profile, Existing vs. Proposed Ashland Creek L.g..d I WS 100 year - Ex Card 700 WS 100 year - GrCorM 100 E f ! Grouts 3 ti j RgM Levee 1880, '~M. 7 j II C 1870 m w I j ! I I j I ' j I,' 1860 II I T I i ! ~ m j o rn, o o ao rn of U') Un rn o l CO r V) r0 a N V 1l N c o + + + L + + + + + + + + N N N N cn -1* 1850 1600 1700 1800 1900 2000 Main Channel Distance (ft) Figure 14: Water Street Culvert 100-Year Water Surface Profile, Existing vs. Proposed Ashland Creek Ley-d WS 100 year • Ex Coral 100 1 WS 100 year • PrCorM 100 E Right LevN I ti i 1860- . t 1 0 i ID 18504 w ~ ~ II a 1840-t a m a ~ it I, 0 0 0 CO n N 9 R 00 + + + ! + c1 + + a) CO i 00 LO LO (0 mI a, m 00 1100 1200 1300 1400 1500 Main Channel Distance (ft) Figure 15: Hersey Street Bridge 100-Year Water Surface Profile, Existing vs. Proposed Ashland Creek 1840 L"'-d WS 100 year. Ex Cono 100 I ~ WS 100 year i PrCono 100E Grano Right Levee 1830 i a m 1820 1810 i OD LnI' °I O, ° r, U + m + t + 0 0 100 200 300 400 Main Channel Distance (ft) Figure 16: All Improvements 100-Year Water Surface Profile, Existing vs. Proposed Ashland Creek Le and WS 100 Year - Ex Conti 100 i WS 100 year - PrCond 100 E 'E7 Ground yM Le~« 1880- ~J I L r 7...__L...~........1 1860- C: .Q ~ I I m > L_ w 1840- N~_ 1820- CD I I m m OI LO LO a' O LO v X Z LO LA rn LO N U) O N O O L. to,., C/) 01 CO LO 0, Ln n rn c o U) rn 7 o CO r- m e v n <n o n c r- co co 7 N cC r- m 0) O CL CO N Cl) 7 rn rn (O W m 01 O O N N V r!+'1 c0+ 1800- r- r r, 11 r` r CO to > m CO CO m m m co CO am rn 0r rn m 0 0 01 0 500 1000 1500 2000 Main Channel Distance (ft) Ashland Creek Legend WS 100yeer-Ex Cond lm I 1940 WS 100year - Prcond 100E Ground RIgM Levee I r 1920- ~ i 1900- 1880 I I I j j c ` o 0 C), LO, C), LO O i o "li N CO, LO `D o t, o O 0 O rfl 110 7 CO 0) -IT Co N 0 00 N O r, 0) + co o p n a + + CO + + + + O + + + + + + + + - + + + + + + 1860- m V) + c o N N v n n m rn rn o N co co v n 0)r° `O^0 00A 0000 0 0 0 0000 a (M 0) (M rn rn 0) - 2000 2500 3000 3500 4000 Main Channel Distance (ft) Appendix A - HEC-RAS Background Information Appendix A Ashland Creek Hydraulic Investigation HEC-RAS Background Information The US Army Corps of Engineers Hydrologic Engineering Center-River Analysis System Program (HEC-RAS), similar to its predecessor HEC-2, is designed to perform one-dimensional hydraulic modeling calculations for natural and constructed channels. Principal advantages of HEC-RAS over HEC-2 is the use of data-graphics interface, user-intuitive input of data, separate hydraulic analysis components, enhanced data storage and management capabilities, and advanced graphics and reporting capabilities. For example, with HEC-RAS, two different scenarios (e.g., different flows and/or channel geometries) can be modeled for the same reach and compared side by side graphically and in a table of user- defined outputs. The current version of HEC-RAS Version 2.0 is intended to calculate water surface elevations for steady-state flows with gradually varied profiles. The basic computation procedure for the model is based on the solution of the one-dimensional energy equation, with energy losses evaluated by friction (Manning's equation) and contraction/expansion coefficients. The momentum equation is used in situations where the water surface profile may be rapidly varying (i.e., hydraulic jumps, bridge/culvert hydraulics, and stream junctions). Various obstructions, such as bridges, culverts, encroachments, weirs, and impinging structures are considered in the model calculations. HEC-RAS also has the capability of assessing impacts to water surface profiles due to channel improvements, proposed hydraulic structures, and levees or flood walls. Basic inputs to the HEC-RAS software are geometric and flow input data. Basic geometric input data includes geometric information (represented by stream channel cross sections), roughness coefficients, distances between reaches, contraction/expansion coefficients, ineffective flow areas, and obstruction data for each cross section. Other geometric data include bridge and culvert configuration information. Flow input data includes the desired flow(s) to be modeled, locations where there are changes in flow, and boundary conditions. P: \ PROJECT \ 7800 \ 7844 \HYDRAUL \ASHLAND.APP Appendix B - Ashland Creek HEC-RAS Information Appendix B Ashland Creek Hydraulic Investigation HEGRAS Information The hydraulic capacity of Ashland Creek structures (bridges and culverts) depends not only upon the available opening area, but also the available head room, the structure itself, and entrance and exit conditions. Increases in water surface elevations caused by the structures are due to the hydraulic capacity of the structure itself, and entrance and exit losses. For Ashland Creek, the culverts were modeled using the more conservative of the energy or momentum equations for low flows (energy grade line below the crown of the structure) and pressure and weir flow for high flows. Pressure flow occurs when the energy grade line is above the crown of the structure and weir flow occurs when the energy grade line is above the top of road. Pedestrian Bridges and other obstructions were modeled using the energy equation for low and high flows. This is an appropriate modeling technique for these structures, since they are perched, have no piers, and losses are due to a loss in conveyance area and an increase in friction (additional wetted perimeter). Roughness coefficients for the study reach range between 0.018 to 0.030 in the channel and primarily between 0.025 to 0.045 in the overbank areas, except for paved areas (streets) at 0.013. All roughness coefficients were based on field trips to the project area and lowered to account for the sediment in the creek. Contraction and expansion coefficients were both set at 0.1 due to the relative steep slope and high velocities in Ashland Creek (ref: Hydraulic Reference Manual, pg 3-20, US Army Corps of Engineers, Hydrologic Engineering Center, April 1997). Results of the existing conditions hydraulic model indicate that the model runs at critical depth for many cross sections, an indication of the relative steepness of Ashland Creek in this reach. Flows used in the hydraulic evaluation are based on flows obtained from the Ashland Creek Hydrologic Investigation by Otak, dated August 27, 1997. The flows obtained from that report are listed in Table B-1. Boundary conditions for the hydraulic runs were set as the most downstream cross section (below Hersey Street) being at critical depth. P:I PROJEM 7800 \7844 \ HYDRAUL \ASHLAND.APP Table B-1: Ashland Creek Hydrology Recurrence Interval, years Flow, cfs 2 950 5 1500 10 1850 25 2450 50 2700 100 3100 The HEC-RAS model can be run using subcritical, critical, or mixed flow regimes. The critical regime does not take into account backwater effects (a major flooding impact) from Ashland Creek structures, since calculations are performed in a upstream to downstream order. Similarly the mixed flow regime also may not take into account backwater impacts due to the computational procedure used in HEC- RAS (ref Hydraulic Reference Manual, pg 4-7, US Army Corps of Engineers, Hydrologic Engineering Center, April 1997). Due to observed significant backwater effects, and also because the subcritical regime is more conservative, the hydraulic analysis for Ashland Creek was performed using the subcritical flow regime. P: \ PROJECT \ 7800 \ 7844 \ HYDRAUL \ASHLAND.APP Appendix C- Existing Ashland Creek Hydraulic Summary Appendix C Ashland Creek Hydraulic Investigation Hydraulic Information Existing Ashland Creek Shown below is a summarization of the culverts/bridges and reaches and their flooding impacts for the evaluated part of Ashland Creek with existing conditions. The backwater increase and length is as compared to no hydraulic structure conditions. Winburn Way and above (Lithia Park Reach) Winburn Way Culvert Capacity: 850 cfs Winburn Way Culvert Return Period: approximately 2 year Maximum Backwater Increase: negligible Backwater Length: negligible Typical Creek Capacity: 1,400 cfs Lateral Inundation: 100 to 300 feet Affected Property: • Split flow into plaza area (right bank) from Winburn Way backwater and creek capacity. • Overflow of Winburn Way. • Hillah Temple (left bank) from Winburn Way backwater. • Lithia Park cafe, Pioneer Hall, and Community building (left bank) from backwater affect of Winburn Way and upstream overflow of Atkinson Memorial Bridge. • Flooding of Winburn Way parallel to creek (left bank), from creek capacity and backwater effect of Winburn Way Culvert, Atkinson Memorial Bridge, and masonry rubble check dams. • Storage building (right bank) from creek capacity. • Butler band shell (left bank) from creek capacity. • Flooding of Lithia Park (right bank) from creek capacity and backwater affects of Winburn Way Culvert, Atkinson Memorial Bridge, and masonry rubble check dams. Winburn Way to Main Street (Calle Guanajuato Reach) Main Street Bridge Capacity: 3,100 cfs Main Street Bridge Return Period: 100 year Maximum Backwater Increase: 5 feet Backwater Length: 165 feet Typical Creek Capacity: 1,700 cfs Lateral Inundation: 80 feet Affected Property: P: \ PROJE CT \ 7800 \ 7844 \ HYDRALTL \ASHL 1ND.APP • Lower portion of buildings (just upstream of Main Street) between plaza and Calle Guanajuato (right bank) from Main Street backwater. • Entire row of buildings between plaza and Calle Guanajuato from creek capacity. Main Street to Lithia Way (Bluebird Park Reach) Lithia Way Culvert Capacity: 1,500 cfs Lithia Way Culvert Return Period: 5 year Maximum Backwater Increase: 6 feet Backwater Length: 255 feet Typical Creek Capacity: 1,400 cfs Lateral Inundation: 60 feet Affected Property: • Thai Pepper and Ashland Creek Bar & Grill (left bank) from Lithia Way backwater and proximity to creek. • 31 Water Street building (right bank) from Lithia Way backwater and proximity to creek. • Overbank overflow of Lithia Way (right bank). Lithia Way to Water Street Water Street Culvert Capacity: 700 cfs Water Street Culvert Return Period: Less than 2 year Maximum Backwater Increase: 4 feet Backwater Length: 120 feet Typical Creek Capacity: 1,500 cfs Lateral Inundation: 140 to 180 feet Affected Property: • New condominiums (left bank), upstream of Water Street, due to Water Street backwater. • Overflow of Water Street. • Beasy's on the Creek (left bank), downstream of Lithia Way, due to creek capacity. Water Street to Van Ness Avenue Van Ness Culvert Capacity: 1,500 cfs Van Ness Culvert Return Period: 5 year Maximum Backwater Increase: 5 feet Backwater Length: 205 feet Typical Creek Capacity: 1,500 cfs Lateral Inundation: 140 to 240 feet Affected Property: • House and garage just upstream of Van Ness (left bank), from Van Ness backwater. • Overflow of Van Ness. • Water Street Inn (left bank) from proximity to creek and from upstream overflow of Water Street. • Water Street flooding from upstream overflow of Water Street. P: \ PROJECT \ 7800 \ 7844 \ HYDRAUL \ ASHLAND.APP • Commercial lot (right bank) just downstream of Water Street, from upstream overflow of Water Street. Southern Pacific Railroad to Hersey Street Hersey Bridge Capacity: 500 cfs Hersey Street Bridge Return Period: Less than 2 year Maximum Backwater Increase: 3.5 feet Backwater Length: 120 feet Typical Creek Capacity: 1,500 cfs Lateral Inundation: 300 feet Affected Property: • Ashland Christian Fellowship and parking lot (right bank), from Hersey backwater and creek capacity. • Proposed skateboard park (left bank), from Hersey backwater and creek capacity. • Overflow of Hersey Street. • Recycling Center (left bank) from upstream overflow of Van Ness Avenue. • Flooding of Water Street from upstream overflow of Van Ness Avenue. P: \ PROJECT \ 7800 \ 7844 \HYDRAUL \ASHLAND.APP Table C-1: Building and Existing 100-year Water Surface Elevations First Adjacent Finished 100-Year Potential Name Cross Floor Water Surface Flood Section Elevation Elevation Depth, feet Butler band shell** 113+80 1935 1936.7 +1.7 Storage Building 112+25 1928.9 1931.5 +2.6 Lithia Park Cafe** 104+10 1904 1903.2 0.8* Pioneer Hall 102+90 1899.4 1899.6 +0.2 Community 102+45 1899 1898.8 0.2* Building** Hillah Temple 100+35 1893.5 1893.6 +0.1 Calle Guanajuato buildings (see Table 2 in body of report) 31 Water Street 92+30 1868.2 1876.4 +8.2 Thai Pepper 92+30 1873 1876.4 +3.4 Restaurant** Ashland Creek Bar & 91+68 1872 1876.2 +4.2 Grill* Beasy's on the Creek 90+10 1869.4 1868.8 0.6* Commercial 87+60 1862 1864.8 +2.8 Property** New Condominiums 87+60 1864.3 1864.8 +0.5 Water Street Inn 86+75 1856.9 1858.9 +2.0 House and Garage** 82+55 1849 1849.2 +0.2 Recycle Center** 80+15 1838 1842.2 +4.2 Ashland Christian 76+75 1832.0 1831.5 0.5* Fellowship* * Height of freeboard (feet) above 100-year water surface elevation. **Approximate first finished floor elevation from survey or City of Ashland topographic map. P: \ PROJECT\ 7800 \ 7844 \ HYDRAUL \ASHLAND APP Table C-2: Building and Existing and Proposed 100-year Water Surface Elevations Finished Exist. Exist. Prop. Prop. Floor Water Flood Water Flood Name Elev. Surface Depth, Surface Depth, Elev feet Elev feet Butler band shell** (113+80) 1935 1936.7 +1.7 1936.7 +1.7 Storage Building (112+25) 1928.9 1931.5 +2.6 1931.5 +2.6 Lithia Park Cafe** (104+10) 1904 1903.2 0.8* 1903.2 0.8* Pioneer Hall (102+90) 1899.4 1899.6 +0.2 1899.6 +0.2 Community Building** 1899 1898.8 0.2* 1898.8 0.2* (102+45) Hillah Temple (100+35) 1893.5 1893.6 +0.1 1892.1 1.4* Lithia Stationers (98+60) 1890.3 1891.4 +1.1 1889.7 0.6* Pilafs Restaurant (98+20) 1888.2 1886.8 1.4* 1888.0 0.2* Masonic Temple (98+20) 1887.4 1886.8 0.6* 1888.0 +0.6 American Trails (97+40) 1879.0 1883.9 +4.9 1882.7 +3.7 Rare Earth (96+45) 1876.2 1881.7 +5.5 1882.6 +6.4 Players Bar (96+45) 1875.4 1881.7 +6.3 1882.6 +7.2 Plaza Cafe (95+90) 1882.8 1881.3 1.5* 1882.8 0 The Blacksheep (95+65) 1880.9 1881.3 +0.4 1882.8 +1.9 Greenleaf Restaurant (95+65) 1878.6 1881.3 +2.7 1882.8 +4.2 Munchies (95+38) 1873.5 1880.6 +7.1 1881.9 +8.4 31 Water Street (92+30) 1868.2 1876.4 +8.2 1872.5 +4.3 Thai Pepper Restaurant** 1873 1876.4 +3.4 1872.5 0.5* (92+30) Ashland Creek Bar & Grill** 1872 1876.2 +4.2 1872.4 +0.4 (91+68) Beasy's on the Creek (90+10) 1869.4 1868.8 0.6* 1867.1 2.3* Commercial Property** 1862 1864.8 +2.8 1863.1 +1.1 (87+60) New Condominiums (87+60) 1864.3 1864.8 +0.5 1863.6 0.7* Water Street Inn (86+75) 1856.9 1858.9 +2.0 1858.9 +2.Q P: \ PROJECT \ 7800 \ 7844 \ HYDRAUL \ASHLAND.APP Table C-2: Building and Existing and Proposed 100-year Water Surface Elevations Finished Exist. Exist. Prop. Prop. Floor Water Flood Water Flood Name Elev. Surface Depth, Surface Depth, Elev feet Elev feet House and Garage** (82+15) 1849 1849.2 +0.2 1846.7 2.3* Recycle Center** (80+15) 1838 1842.2 +4.2 1842.2 +4.2 Ashland Christian Fellowship 1832.0 1831.5 0.5* 1831.5 0.5* (76+75) * Height of freeboard (feet) above 100-year water surface elevation. **Approximate first finished floor elevation from survey or City of Ashland topographic map. P: \ PROJECT \ 7800 \ 7844 \ HYDRAUL \ASHLAND.APP Appendix D - HEC-RAS Output Tables Table D-1: HEC-RAS Output, Winburn Way Culvert Replacement Structure Only, with Floodwall HEC-RAS River: Ashland Cr Reach: River Sta Q Total Min Ch El W.S. Elev Crit W.S. E.G. Elev E.G. Slope Vel Chnl Flow Area Top Width Cross Section Condition da ft ft ft $ $l ftlaec aq-ft $ 102.9 Ex Cond 100 * 3100 1891.30 1899.60 1899.60 1901.12 0.00463 10.74 340.38 100.67 102.9 WW 3100 1891.30 1899.60 1899.60 1901.12 0.00463 10.74 340.38 100.67 102.45 Ex Cond 100 3100 1890.30 1898.83 1898.83 1899.96 0.00306 9.33 405.38 160.98 102.45 WW 3100 1890.30 1898.83 1898.83 1899.96 0.00306 9.33 405.38 160.98 101.9 Ex Cond 100 3100 1888.14 1897.55 1897.55 1898.60 0.00297 9.48 425.17 174.86 101.9 WW 3100 1888.14 1897.51 1897.51 1898.70 0.00325 9.88 381.26 135.21 101.3 Ex Cond 100 3100 1886.47 1895.32 1895.32 1896.29 0.00306 8.81 441.09 200.00 101.3 WW 3100 1886.47 1895.42 1895.42 1896.77 0.00371 9.79 344.16 113.64 100.85 Ex Cond. 100 3100 1884.71 1894.44 1894.44 1895.41 0.00288 8.70 457.22 224.96 100.85 WW 3100 1884.71 1892.26 1892.26 1894.98 0.00848 13.25 234.07 45.10 100.7 WW 3100 1884.30 1891.78 1891.78 1894.76 0.00887 13.86 223.70 38.19 100.35 Ex Cond. 100 3100 1883.36 1893.57 1893.57 1894.42 0.00238 8.62 496.44 258.64 100.35 WW 3100 1883.36 1892.12 1889.88 1893.56 0.00388 9.62 322.14 41.00 100.1 WW 3100 1882.00 1891.68 1888.92 1893.43 0.00411 10.62 291.95 30.22 99.9 Ex Cond 100 2400 1882.12 1892.36 1890.01 1892.78 0.00036 5.84 662.25 310.58 99.8 Winburn Way 99.35 WW 3100 1879.85 1889.18 1886.50 1890.87 0.00078 10.41 297.65 31.97 99.1 WW 3100 1879.80 1889.18 1890.85 0.00077 10.36 299.18 31.99 98.6 Ex Cond 100 2400 1879.76 1891.41 1891.41 1892.73 0.00166 10.36 278.17 87.11 98.6 WW 3100 1879.76 1889.16 1890.81 0.00075 10.31 306.33 52.51 98.55 WW 3100 1879.76 1889.72 1890.73 0.00217 8.14 393.23 66.93 98.2 Ex Cond 100 2400 1878.21 1886.81 1886.81 1889.46 0.00544 13.09 187.37 39.38 98.2 WW 3100 1878.21 1889.19 1890.62 0.00208 10.15 344.46 84.07 98.19 Ex Cond 100 2400 1877.69 1886.69 1886.69 1889.37 0.00477 13.17 185.71 38.54 98.19 WW 3100 1877.69 1888.79 1888.79 1890.57 0.00229 11.20 314.54 83.42 97.7 Ex Cond 100 2400 1875.52 1885.47 1883.70 1887.27 0.00333 10.76 224.46 31.47 97.7 WW 3100 1875.52 1884.86 1884.86 1888.40 0.00733 15.11 205.57 30.12 97.4 Ex Cond. 100 2400 1876.97 1883.87 1883.87 1887.00 0.00580 14.25 172.65 30.35 97.4 WW 3100 1875.51 1886.09 1886.09 1887.93 0.00427 11.65 348.36 107.95 97.05 Ex Cond 100 2400 1874.62 1884.07 1884.07 1885.51 0.01012 10.06 254.18 76.58 97.05 WW 3100 1874.59 1884.58 1884.58 1886.26 0.00239 11.10 333.80 91.32 96.7 Ex Cond. 100 2400 1873.46 1881.24 1881.24 1883.81 0.00522 13.27 207.67 44.05 96.7 WW 3100 1873.46 1883.11 1883.11 1885.19 0.00321 12.29 313.74 76.57 96.45 Ex Cond. 100 2400 1872.47 1881.68 1880.46 1882.88 0.00234 9.12 296.34 66.97 96.45 WW 3100 1872.47 1883.21 1881.42 1884.25 0.00164 8.73 418.86 91.03 96.4 Ped. Bridge 96.35 Ex Cond 100 2400 1873.24 1880.50 1880.50 1882.37 0.00373 11.36 244.11 69.01 96.35 WW 3100 1873.24 1882.45 1883.63 0.00171 9.65 408.30 96.52 95.9 Ex Cond 100 2400 1871.16 1881.32 1881.95 0.00139 6.98 405.99 94.96 95.9 WW 3100 1871.16 1882.97 1883.52 0.00084 6.17 566.58 98.09 95.65 Ex Cond. 100 2400 1870.52 1881.33 1881.91 0.00132 6.70 416.16 81.04 95.65 WW 3100 1870.52 1882.96 1883.50 0.00094 6.36 547.59 81.07 95.6 Ex Cond 100 2400 1870.52 1881.02 1881.87 0.00198 8.26 347.60 79.04 95.6 WW 3100 1870.52 1882.78 1883.47 0.00118 7.16 486.91 79.07 Table D-1: HEC-RA.S Output, Winburn Way Culvert Replacement Structure Only, with Floodwall HEC-RAS River: Ashland Cr Reach: River Sta Q Total Min Ch El W.S. Elev Crit W.S. E.G. Elev E.G. Slope Vel Chnl Flow Area Top Width Cross Section Condition sa a ft ft it &/sec aq-ft 1t 95.4 Ex Cond 100 2400 1869.89 1879.80 1881.71 0.00480 11.64 226.97 43.08 95.4 WW 3100 1869.89 1882.05 1883.38 0.00253 9.73 345.99 57.61 95.38 Ex Cond 100 2400 1869.89 1880.61 1881.61 0.00236 8.39 309.40 55.38 95.38 WW 3100 1869.89 1882.39 1883.33 0.00166 7.97 410.89 57.98 94.7 Ex Cond 100 2400 1868.72 1880.50 1881.51 0.00107 6.09 333.06 50.31 94.7 WW 3100 1868.72 1882.09 1883.23 0.00091 6.13 414.35 51.96 94 Ex Cond 100 2400 1865.57 1880.73 1873.92 1881.42 0.00069 6.66 360.45 76.54 94 WW 3100 1865.57 1882.23 1875.04 1883.15 0.00079 7.70 402.41 97.71 93.6 Main Street Bridge 93.25 Ex Cond 100 2400 1864.79 1875.69 1872.12 1877.14 0.00216 9.67 248.20 92.97 93.25 WW 3100 1864.79 1873.60 1873.36 1877.40 0.00762 15.63 198.28 92.15 92.75 Ex Cond 100 3100 1863.45 1876.68 1877.00 0.00035 4.57 705.39 82.66 92.75 WW 3100 1863.45 1876.68 1877.00 0.00035 4.57 705.39 82.66 92.45 Ex Cond 100 3100 1861.59 1876.30 1876.95 0.00071 7.15 497.04 53.65 92.45 WW 3100 1861.59 1876.30 1876.95 0.00071 7.15 497.04 53.65 *Existing Conditions - 100 Year Flow Event Winburn Way Culvert Replacement Structure only, with Floodwall p:\ \ 7844 \ hydraul\ dtables.wk4 f 1d) Table D-2: HEC-R.AS Output, Winburn Way Culvert Replacement Structure Only, without Floodwall HEC-RAS River: Ashland Cr Reach: River Sta Q Total Min Ch El W.S. Elev Crit W.S. E.G. Elev E.G. Slope Vel Chnl Flow Area Top Width Cross Section Condition ds fl; ft fl ft fttft ft/sec aq-ft ft 102.9 Ex Cond 100 * 3100 1891.30 1899.60 1899.60 1901.12 0.00463 10.74 340.38 100.67 102.9 WW no fwalls 3100 1891.30 1899.60 1899.60 1901.12 0.00463 10.74 340.38 100.67 102.45 Ex Cond 100 3100 1890.30 1898.83 1898.83 1899.96 0.00306 9.33 405.38 160.98 102.45 WW no fwalls 3100 1890.30 1898.83 1898.83 1899.96 0.00306 9.33 405.38 160.98 101.9 Ex Cond 100 3100 1888.14 1897.55 1897.55 1898.60 0.00297 9.48 425.17 174.86 101.9 WW no fwalls 3100 1888.14 1897.55 1897.55 1898.60 0.00297 9.48 425.17 174.86 101.3 Ex Cond 100 3100 1886.47 1895.32 1895.32 1896.29 0.00306 8.81 441.09 200.00 101.3 WW no fwalls 3100 1886.47 1895.32 1895.32 1896.29 0.00306 8.81 441.09 200.00 100.85 Ex Cond 100 3100 1884.71 1894.44 1894.44 1895.41 0.00288 8.70 457.22 224.96 100.85 WW no fwalls 3100 1884.71 1892.37 1892.37 1894.98 0.00799 12.97 240.50 55.86 100.7 WW no fwalls 3100 1884.30 1891.95 1891.95 1894.57 0.00805 13.00 239.75 55.12 100.35 Ex Cond 100 3100 1883.36 1893.57 1893.57 1894.42 0.00238 8.62 496.44 258.64 100.35 WW no fwalls 3100 1883.36 1889.88 1889.88 1892.68 0.01062 13.45 230.55 41.17 100.1 WW no fwalls 3100 1882.00 1891.41 1888.67 1892.35 0.00176 7.79 456.02 215.69 99.9 Ex Cond 100 2400 1882.12 1892.36 1890.01 1892.78 0.00036 5.84 662.25 310.58 99.8 Winburn Way 99.35 WW no fwalls 3100 1879.85 1889.18 1886.50 1890.87 0.00078 10.41 297.65 31.97 99.1 WW no fwalls 3100 1879.80 1889.18 1890.85 0.00077 10.36 299.18 31.99 98.6 Ex Cond 100 2400 1879.76 1891.41 1891.41 1892.73 0.00166 10.36 278.17 87.11 98.6 WW no (walls 3100 1879.76 1889.16 1890.81 0.00075 10.31 306.33 52.51 98.55 WW no fwalls 3100 1879.76 1889.72 1890.73 0.00217 8.14 393.23 66.93 98.2 Ex Cond 100 2400 1878.21 1886.81 1886.81 1889.46 0.00544 13.09 187.37 39.38 98.2 WW no fwalls 3100 1878.21 1889.19 1890.62 0.00208 10.15 344.46 84.07 98.19 Ex Cond 100 2400 1877.69 1886.69 1886.69 1889.37 0.00477 13.17 185.71 38.54 98.19 WW no fwalls 3100 1877.69 1888.79 1888.79 1890.57 0.00229 11.20 314.54 83.42 97.7 Ex Cond 100 2400 1875.52 1885.47 1883.70 1887.27 0.00333 10.76 224.46 31.47 97.7 WW no fwalls 3100 1875.52 1884.86 1884.86 1888.40 0.00733 15.11 205.57 30.12 97.4 Ex Cond 100 2400 1876.97 1883.87 1883.87 1887.00 0.00580 14.25 172.65 30.35 97.4 WW no fwalls 3100 1875.51 1886.09 1886.09 1887.93 0.00427 11.65 348.36 107.95 97.05 Ex Cond 100 2400 1874.62 1884.07 1884.07 1885.51 0.01012 10.06 254.18 76.58 97.05 WW no fwalls 3100 1874.59 1884.58 1884.58 1886.26 0.00239 11.10 333.80 91.32 96.7 Ex Cond 100 2400 1873.46 1881.24 1881.24 1883.81 0.00522 13.27 207.67 44.05 96.7 WW no fwalls 3100 1873.46 1883.11 1883.11 1885.19 0.00321 12.29 313.74 76.57 96.45 Ex Cond 100 2400 1872.47 1881.68 1880.46 1882.88 0.00234 9.12 296.34 66.97 96.45 WW no fwalls 3100 1872.47 1883.21 1881.42 1884.25 0.00164 8.73 418.86 91.03 96.4 Ped. Bridge 96.35 Ex Cond 100 2400 1873.24 1880.50 1880.50 1882.37 0.00373 11.36 244.11 69.01 96.35 WW no fwalls 3100 1873.24 1882.45 1883.63 0.00171 9.65 408.30 96.52 95.9 Ex Cond 100 2400 1871.16 1881.32 1881.95 0.00139 6.98 405.99 94.96 95.9 WW no fwalls 3100 1871.16 1882.97 1883.52 0.00084 6.17 566.58 98.09 95.65 Ex Cond 100 2400 1870.52 1881.33 1881.91 0.00132 6.70 416.16 81.04 95.65 WW no fwalls 3100 1870.52 1882.96 1883.50 0.00094 6.36 547.59 81.07 95.6 Ex Cond 100 2400 1870.52 1881.02 1881.87 0.00198 8.26 347.60 79.04 95.6 WW no fwalls 3100 1870.52 1882.78 1883.47 0.00118 7.16 486.91 79.07 95.4 Ex Cond 100 2400 1869.89 1879.80 1881.71 0.00480 11.64 226.97 43.08 Table D-2: HEC-RAS Output, Winburn Way Culvert Replacement Structure Only, without Floodwall HEC-RAS River: Ashland Cr Reach: River Sta Q Total Min Ch El W.S. Elev Crit W.S. E.G. Elev E.G. Slope Vel Chnl Flow Area Top Width Cross Section Condition d2 ft ft f; ft &AU ft 95.4 WW no fwalls 3100 1869.89 1882.05 1883.38 0.00253 9.73 345.99 57.61 95.38 Ex Cond 100 2400 1869.89 1880.61 1881.61 0.00236 8.39 309.40 55.38 95.38 WW no fwalls 3100 1869.89 1882.39 1883.33 0.00166 7.97 410.89 57.98 94.7 Ex Cond 100 2400 1868.72 1880.50 1881.51 0.00107 6.09 333.06 50.31 94.7 WW no (walls 3100 1868.72 1882.09 1883.23 0.00091 6.13 414.35 51.96 94 Ex Cond 100 2400 1865.57 1880.73 1873.92 1881.42 0.00069 6.66 360.45 76.54 94 WW no (walls 3100 1865.57 1882.23 1875.04 1883.15 0.00079 7.70 402.41 97.71 93.6 Main Street Bridge 93.25 Ex Cond 100 2400 1864.79 1875.69 1872.12 1877.14 0.00216 9.67 248.20 92.97 93.25 WW no fwalls 3100 1864.79 1873.60 1873.36 1877.40 0.00762 15.63 198.28 92.15 92.75 Ex Cond 100 3100 1863.45 1876.68 1877.00 0.00035 4.57 705.39 82.66 92.75 WW no fwalls 3100 1863.45 1876.68 1877.00 0.00035 4.57 705.39 82.66 92.45 Ex Cond 100 3100 1861.59 1876.30 1876.95 0.00071 7.15 497.04 53.65 92.45 WW no fwalls 3100 1861.59 1876.30 1876.95 0.00071 7.15 497.04 53.65 * Existing Conditions - 100 Year Flow Event Winburn Way Culvert Replacement Structure only, without Floodwall p:\...\7844\hydraul\dtab1e .wk4 {2dl Table D-3: HEC-RAS Output, Calle Guanajuato Reach HEC-RAS River: Ashland Cr Reach: River Sta Q Total Min Ch El W.S. Elev Crit W.S. E.G. Elev E.G. Slope Vel Chnl Flow Area Top Width Cross Section Condition d a A ft a ft 1 ft/sec aqA ft 102.9 Ex Cond 100 * 3100 1891.30 1899.60 1899.60 1901.12 0.00463 10.74 340.38 100.67 102.9 PrCond 100 E 3100 1891.30 1899.60 1899.60 1901.12 0.00463 10.74 340.38 100.67 102.45 Ex Cond 100 3100 1890.30 1898.83 1898.83 1899.96 0.00306 9.33 405.38 160.98 102.45 PrCond 100 E 3100 1890.30 1898.83 1898.83 1899.96 0.00306 9.33 405.38 160.98 101.9 Ex Cond 100 3100 1888.14 1897.55 1897.55 1898.60 0.00297 9.48 425.17 174.86 101.9 PrCond 100 E 3100 1888.14 1897.51 1897.51 1898.70 0.00325 9.88 381.26 135.21 101.3 Ex Cond 100 3100 1886.47 1895.32 1895.32 1896.29 0.00306 8.81 441.09 200.00 101.3 PrCond 100 E 3100 1886.47 1895.42 1895.42 1896.77 0.00371 9.79 344.16 113.64 100.85 Ex Cond 100 3100 1884.71 1894.44 1894.44 1895.41 0.00288 8.70 457.22 224.96 100.85 PrCond 100 E 3100 1884.71 1892.26 1892.26 1894.98 0.00848 13.25 234.07 45.10 100.7 PrCond 100 E 3100 1884.30 1891.78 1891.78 1894.76 0.00887 13.86 223.70 38.19 100.35 Ex Cond 100 3100 1883.36 1893.57 1893.57 1894.42 0.00238 8.62 496.44 258.64 100.35 PrCond 100 E 3100 1883.36 1892.12 1889.88 1893.56 0.00388 9.62 322.14 41.00 100.1 PrCond 100 E 3100 1882.00 1891.68 1888.92 1893.43 0.00411 10.62 291.95 30.22 99.9 Ex Cond 100 2400 1882.12 1892.36 1890.01 1892.78 0.00036 5.84 662.25 310.58 99.8 Winhurn Way 99.35 PrCond 100 E 3100 1879.85 1889.70 1886.48 1891.22 0.00067 9.86 314.27 45.62 99.1 PrCond 100 E 3100 1879.80 1889.70 1886.44 1891.20 0.00066 9.81 316.69 39.33 98.6 Ex Cond 100 2400 1879.76 1891.41 1891.41 1892.73 0.00166 10.36 278.17 87.11 98.6 PrCond 100 E 3100 1879.76 1889.67 1886.41 1891.16 0.00064 9.79 320.88 48.24 98.55 PrCond 100 E 3100 1879.76 1890.16 1886.24 1891.10 0.00193 7.81 400.21 55.86 98.2 Ex Cond 100 2400 1878.21 1886.81 1886.81 1889.46 0.00544 13.09 187.37 39.38 98.2 PrCond 100 E 3100 1878.21 1888.04 1888.04 1890.82 0.00467 13.51 239.75 45.16 98.19 Ex Cond 100 2400 1877.69 1886.69 1886.69 1889.37 0.00477 13.17 185.71 38.54 98.19 PrCond 100 E 3100 1877.69 1887.94 1887.94 1890.75 0.00409 13.57 238.59 45.00 97.7 Ex Cond 100 2400 1875.52 1885.47 1883.70 1887.27 0.00333 10.76 224.46 31.47 97.7 PrCond 100 E 3100 1875.52 1884.50 1884.50 1887.54 0.00904 13.99 221.59 36.54 97.4 Ex Cond 100 2400 1876.97 1883.87 1883.87 1887.00 0.00580 14.25 172.65 30.35 97.4 PrCond 100 E 3100 1875.51 1882.68 1882.68 1885.39 0.00878 13.21 234.60 43.52 97.05 Ex Cond 100 2400 1874.62 1884.07 1884.07 1885.51 0.01012 10.06 254.18 76.58 97.05 PrCond 100 E 3100 1874.59 1881.89 1881.89 1884.72 0.00755 13.53 231.72 43.19 96.7 Ex Cond 100 2400 1873.46 1881.24 1881.24 1883.81 0.00522 13.27 207.67 44.05 96.7 PrCond 100 E 3100 1873.46 1881.48 1880.81 1883.85 0.00532 12.42 260.03 44.80 96.45 Ex Cond 100 2400 1872.47 1881.68 1880.46 1882.88 0.00234 9.12 296.34 66.97 96.45 PrCond 100 E 3100 1872.47 1882.58 1880.50 1883.64 0.00202 8.48 393.64 67.68 96.4 Ped. Bridge 96.35 Ex Cond 100 2400 1873.24 1880.50 1880.50 1882.37 0.00373 11.36 244.11 69.01 96.35 PrCond 100 E 3100 1873.24 1882.46 1880.87 1883.51 0.00213 8.62 400.80 77.23 95.9 Ex Cond 100 2400 1871.16 1881.32 1881.95 0.00139 6.98 405.99 94.96 95.9 PrCond 100 E 3100 1871.16 1882.84 1879.53 1883.41 0.00093 6.40 544.99 81.24 95.65 Ex Cond 100 2400 1870.52 1881.33 1881.91 0.00132 6.70 416.16 81.04 95.65 PrCond 100 E 3100 1870.52 1882.78 1879.14 1883.38 0.00101 6.61 519.65 68.49 95.6 Ex Cond 100 2400 1870.52 1881.02 1881.87 0.00198 8.26 347.60 79.04 95.6 PrCond 100 E 3100 1870.52 1882.34 1879.75 1883.33 0.00176 8.51 407.98 57.16 Table D-3: HEC-RAS Output, Calle Guanajuato Reach HEC-RAS River: Ashland Cr Reach: River Sta Q Total Min Ch El W.S. Elev Crit W.S. E.G. Elev E.G. Slope Vel Chnl Flow Area Top Width Cross Section Condition da ft ft ft ft ft & ft/sec eft fl_ 95.4 Ex Cond 100 2400 1869.89 1879.80 1881.71 0.00480 11.64 226.97 43.08 95.4 PrCond 100 E 3100 1869.89 1881.19 1879.03 1883.18 0.00352 11.38 278.95 33.59 95.38 Ex Cond 100 2400 1869.89 1880.61 1881.61 0.00236 8.39 309.40 55.38 95.38 PrCond 100 E 3100 1869.89 1881.90 1878.55 1883.10 0.00201 8.84 359.12 42.38 94.7 Ex Cond 100 2400 1868.72 1880.50 1881.51 0.00107 6.09 333.06 50.31 94.7 PrCond 100 E 3100 1868.72 1881.78 1883.00 0.00103 6.41 398.04 51.63 94 Ex Cond 100 2400 1865.57 1880.73 1873.92 1881.42 0.00069 6.66 360.45 76.54 94 PrCond 100 E 3100 1865.57 1881.95 1875.04 1882.91 0.00085 7.85 394.68 96.69 93.6 Main Street Bridge * Existing Conditions - 100 Year Flow Event Calle Guanajuato Reach - 100 Year Flow Event p:\...\7844\hydraul\dtable .wk4 J3d{ Table D-4: HEC-RAS Output, Lithia Way Culvert and Bluebird Park Reach HEC-RAS River: Ashland Cr Reach: River Sta. Q Total Min Ch El W.S. Elev Crit W.S. E.G. Elev E.G. Slope Vel Chni Flow Area Top Width Cross Section Condition rfa it ft ft ft& fl/ aq-f 93.6 :Main Street Bridge 93.25 Ex Cond 100 * 2400 1864.79 1875.69 1872.12 1877.14 0.00216 9.67 248.20 92.97 93.25 PrCond 100 E 3100 1864.79 1873.36 1873.36 1877.39 0.00841 16.10 192.53 92.06 92.75 Ex Cond 100 3100 1863.45 1876.68 1877.00 0.00035 4.57 705.39 82.66 92.75 PrCond 100 E 3100 1863.45 1873.71 1874.43 0.00126 7.14 465.26 78.32 92.45 Ex Cond 100 3100 1861.59 1876.30 1876.95 0.00071 7.15 497.04 53.65 92.45 PrCond 100 E 3100 1861.59 1871.62 1871.62 1874.18 0.00487 14.16 257.06 46.98 92.3 Ex Cond 100 3100 1861.80 1876.43 1870.79 1876.92 0.00125 4.31 712.84 79.82 92.3 PrCond 100 E 3100 1861.80 1872.53 1873.51 0.00230 10.15 490.03 77.11 92.2 Ex Cond 100 3100 1861.80 1875.17 1870.30 1876.78 0.01055 11.63 396.04 43.03 92.2 PrCond 100 E 3100 1861.80 1871.50 1873.38 0.00469 13.48 361.71 53.21 92.05 Ex Cond 100 3100 1862.27 1874.11 1876.62 0.00266 12.70 244.79 22.03 92.05 PrCond 100 E 3100 1862.27 1871.94 1873.29 0.00213 9.75 341.90 47.96 91.76 Ex Cond 100 3100 1861.11 1876.20 1869.45 1876.37 0.00015 3.63 940.59 128.98 91.76 PrCond 100 E 3100 1861.11 1872.47 1869.45 1873.18 0.00097 7.11 486.44 107.62 91.72 Ped. Bridge 91.68 Ex Cond 100 3100 1861.11 1876.18 1876.35 0.00018 3.46 938.16 128.98 91.68 PrCond 100 E 3100 1861.11 1872.43 1873.13 0.00125 7.03 482.71 107.27 91.5 Ex Cond 100 3100 1860.76 1876.16 1876.34 0.00022 3.50 891.79 129.07 91.5 PrCond 100 E 3100 1860.76 1872.57 1873.09 0.00095 6.07 550.87 108.88 91.1 Ex Cond 100 3100 1859.88 1875.77 1872.67 1876.30 0.00033 6.74 571.56 100.96 91.1 PrCond 100 E 3100 1859.88 1871.75 1867.10 1873.00 0.00035 8.96 346.08 60.83 90.9 Lithia Way Culvert * Existing Conditions - 100 Year Flow Event Lithia Way and Bluebird Park Reach - 100 Year Flow Event p:\ \ 7844 \ hydraul \ dtables.wk4 [4d) Table D-5: HEC-RAS Output, Water Street Culvert HEC-RAS River: Ashland Cr Reach: River Sta Q Total Min Ch El W.S. Elev Crit W.S. E.G. Elev E.G. Slope Vel Chnl Flow Area Top Width Cross Section Condition da ljr ft ft a ft/sec 59L-ft ft 88.8 Ex Cond 100 * 3100 1853.74 1863.61 1863.61 1865.83 0.00676 12.36 280.65 75.10 88.8 PrCond 100 E 3100 1853.74 1863.61 1863.61 1865.83 0.00676 12.36 280.65 75.10 88.4 Ex Cond 100 3100 1853.73 1864.09 1865.20 0.00257 9.01 419.14 132.66 88.4 PrCond 100 E 3100 1853.73 1862.74 1862.74 1864.96 0.00621 12.23 276.04 71.25 87.6 Ex Cond 100 3100 1851.15 1864.82 1861.41 1865.05 0.00032 4.04 851.13 143.86 87.6 PrCond 100 E 3100 1851.15 1863.59 1858.99 1863.96 0.00058 5.03 680.02 132.04 87.5 Water Street Culvert * Existing Conditions - 100 Year Flow Event Water Street Culvert - 100 Year Flow Event Table D-6: HEC-RAS Output, Hersey Street Bridge HEC-RAS River: Ashland Cr Reach: River Sts. Q Total Vlin Ch El W.S. Elev Crit W.S. E.G. Elev E.G. Slope Vel Chnl Flow Area Top Width Cross Section Condition cfs 1 R f~/sec %Lff 1 80.7 SPRR Culvert 80.5 Ex Cond 100 * 3100 1833.81 1843.53 1843.53 1848.21 0.00623 17.36 178.59 70.33 80.5 PrCond 100 E 3100 1833.81 1843.53 1843.53 1848.21 0.00623 17.36 178.59 70.33 80.15 Ex Cond 100 3100 1833.44 1842.21 1842.21 1843.12 0.00277 8.47 420.18 207.34 80.15 PrCond 100 E 3100 1833.44 1842.21 1842.21 1843.12 0.00277 8.47 420.18 207.34 80.14 Ex Cond 100 3100 1830.43 1842.17 1842.17 1843.09 0.00268 8.63 434.24 205.23 80.14 PrCond 100 E 3100 1830.43 1842.17 1842.17 1843.09 0.00268 8.63 434.24 205.23 79.05 Ex Cond. 100 3100 1829.16 1836.14 1836.14 1837.14 0.00372 8.13 386.50 190.02 79.05 PrCond 100 E 3100 1829.16 1836.14 1836.14 1837.14 0.00372 8.13 386.50 190.02 78.4 Ex Cond 100 3100 1827.21 1834.82 1834.82 1835.67 0.00351 8.14 423.08 232.38 78.4 PrCond 100 E 3100 1827.21 1834.82 1834.82 1835.67 0.00351 8.14 423.08 232.38 77.5 Ex Cond 100 3100 1825.14 1832.67 1832.67 1833.90 0.00416 8.91 348.45 141.31 77.5 PrCond 100 E 3100 1825.14 1832.67 1832.67 1833.90 0.00416 8.91 348.45 141.31 76.75 Ex Cond 100 3100 1823.25 1831.50 1831.50 1833.09 0.00476 10.39 308.15 93.86 76.75 PrCond 100 E 3100 1823.25 1831.50 1831.50 1833.09 0.00476 10.39 308.15 93.86 76 Ex Cond 100 3100 1821.58 1830.88 1831.32 0.00059 4.43 615.13 147.54 76 PrCond 100 E 3100 1821.58 1829.25 1830.09 0.00179 6.71 429.73 120.28 75.55 Ex Cond 100 3100 1819.08 1831.10 1828.68 1831.29 0.00035 4.22 931.51 260.72 75.55 PrCond 100 E 3100 1819.08 1829.73 1826.31 1830.00 0.00055 4.38 766.03 199.74 75.25 Hersey Street Bridge 74.9 Ex Cond 100 3100 1816.12 1827.49 1827.49 1828.84 0.00360 9.97 405.81 171.31 74.9 PrCond 100 E 3100 1816.12 1823.16 1823.16 1826.40 0.00995 14.43 214.78 33.01 73.8 Ex Cond 100 3100 1815.36 1822.36 1822.36 1823.29 0.00338 8.84 503.52 240.87 73.8 PrCond 100 E 3100 1815.36 1822.36 1822.36 1823.29 0.00338 8.84 503.52 240.87 * Existing Conditions - 100 Year Flow Event Hersey Street Bridge - 100 Year Flow Event p:\...\7844\hydr ut\dtable .wk4I6d) Table D-7: HEC-RAS Output, All Improvements HEC-RAS River: Ashland Cr Reach: River Sta Q Total Min Ch El W.S. Elev Crit W.S. E.G. Elev E.G. Slope Vel Chn1 Flow Area Top Width Cross Section Condition da ft fl ft f1: ft d ft/sec SA-ft ft 115.9 Ex Cond 100 * 3100 1932.95 1941.64 1943.26 0.00648 10.80 345.58 87.54 115.9 PrCond 100 E 3100 1932.95 1941.64 1943.26 0.00648 10.80 345.58 87.54 115.2 Ex Cond. 100 3100 1930.31 1942.26 1940.51 1942.90 0.00241 6.78 509.75 111.92 115.2 PrCond 100 E 3100 1930.31 1942.26 1940.51 1942.90 0.00241 6.78 509.75 111.92 115.15 Ped. Bridge 115.1 Ex Cond 100 3100 1930.31 1940.51 1940.51 1942.15 0.00834 10.68 320.59 101.62 115.1 PrCond 100 E 3100 1930.31 1940.51 1940.51 1942.15 0.00834 10.68 320.59 101.62 114.75 Ex Cond 100 3100 1929.62 1938.50 1938.50 1939.83 0.00626 10.07 353.70 122.07 114.75 PrCond 100 E 3100 1929.62 1938.50 1938.50 1939.83 0.00626 10.07 353.70 122.07 113.8 Ex Cond 100 3100 1927.52 1936.66 1936.66 1938.47 0.00809 11.66 308.25 84.02 113.8 PrCond 100 E 3100 1927.52 1936.66 1936.66 1938.47 0.00809 11.66 308.25 84.02 113.06 Ex Cond 100 3100 1926.06 1934.12 1934.12 1935.16 0.00444 9.22 423.57 175.17 113.06 PrCond 100 E 3100 1926.06 1934.12 1934.12 1935.16 0.00444 9.22 423.57 175.17 112.25 Ex Cond 100 3100 1921.37 1931.54 1931.54 1932.76 0.00510 9.95 397.59 173.03 112.25 PrCond 100 E 3100 1921.37 1931.54 1931.54 1932.76 0.00510 9.95 397.59 173.03 111.75* Ex Cond 100 3100 1920.65 1930.50 1930.50 1931.75 0.00398 10.11 410.39 165.95 111.75* PrCond 100 E 3100 1920.65 1930.50 1930.50 1931.75 0.00398 10.11 410.39 165.95 111.25 Ex Cond 100 3100 1919.93 1930.11 1928.83 1930.56 0.00153 5.83 631.94 199.02 111.25 PrCond 100 E 3100 1919.93 1930.11 1928.83 1930.56 0.00153 5.83 631.94 199.02 111.18 Ped. Bridge 111.1 Ex Cond. 100 3100 1919.18 1928.20 1928.20 1929.49 0.00555 9.68 359.68 148.20 111.1 PrCond 100 E 3100 1919.18 1928.20 1928.20 1929.49 0.00555 9.68 359.68 148.20 110.83 Ex Cond 100 3100 1920.39 1926.11 1926.11 1927.36 0.00407 9.23 359.65 162.40 110.83 PrCond 100 E 3100 1920.39 1926.11 1926.11 1927.36 0.00407 9.23 359.65 162.40 110.1 Ex Cond 100 3100 1921.02 1925.34 1925.34 1926.40 0.00352 9.01 408.17 187.40 110.09 Ex Cond 100 3100 1915.83 1924.64 1924.64 1925.89 0.00295 9.58 381.90 145.43 110.09 PrCond 100 E 3100 1915.83 1924.64 1924.64 1925.89 0.00295 9.58 381.90 145.43 109.95 Ex Cond 100 3100 1916.77 1924.38 1924.38 1925.38 0.00374 8.65 409.45 200.14 109.95 PrCond 100 E 3100 1916.77 1924.38 1924.38 1925.38 0.00374 8.65 409.45 200.14 109.45 Ex Cond 100 3100 1917.82 1922.90 1922.90 1923.86 0.00454 8.41 412.34 206.14 109.44 Ex Cond 100 3100 1911.87 1920.39 1921.87 0.00396 9.76 317.47 52.96 109.44 PrCond 100 E 3100 1911.87 1920.40 1921.87 0.00394 9.75 318.06 53.00 109.25 Ex Cond 100 3100 1911.15 1919.01 1919.01 1921.65 0.00808 13.04 237.75 45.30 109.25 PrCond 100 E 3100 1911.15 1919.01 1919.01 1921.65 0.00808 13.04 237.75 45.30 108.5 Ex Cond 100 3100 1907.11 1916.60 1916.60 1919.41 0.01228 13.44 230.72 41.58 108.5 PrCond 100 E 3100 1907.11 1916.60 1916.60 1919.41 0.01228 13.44 230.72 41.58 107.85 Ex Cond 100 3100 1905.80 1915.34 1915.34 1917.49 0.00615 12.07 274.51 62.39 107.85 PrCond 100 E 3100 1905.80 1915.34 1915.34 1917.49 0.00615 12.07 274.51 62.39 107 Ex Cond 100 3100 1903.35 1913.27 1913.27 1914.32 0.00319 9.34 448.91 204.55 107 PrCond 100 E 3100 1903.35 1913.27 1913.27 1914.32 0.00319 9.34 448.91 204.55 106.58* Ex Cond 100 3100 1902.12 1912.25 1912.25 1913.22 0.00181 8.82 493.76 260.37 106.58* PrCond 100 E 3100 1902.12 1912.25 1912.25 1913.22 0.00181 8.82 493.76 260.37 106.17* Ex Cond 100 3100 1900.88 1910.77 1910.77 1911.98 0.00212 9.37 428.55 214.28 106.17* PrCond 100 E 3100 1900.88 1910.77 1910.77 1911.98 0.00212 9.37 428.55 214.28 105.75 Ex Cond 100 3100 1899.65 1910.91 1908.09 1911.17 0.00063 4.77 848.38 325.42 105.75 PrCond 100 E 3100 1899.65 1910.91 1908.09 1911.17 0.00063 4.77 848.38 325.42 Table D-7: HEC-RAS Output, All Improvements HEC-RAS River: Ashland Cr Reach: River Sta Q Total Min Ch El W.S. Elev Crit W.S. E.G. Elev E.G. Slope Vel Chnl Flow Area Top Width Cross Section Condition sfs ft ll: It ft a& ft/sec 105.7 Atkinson Memorial Bridge 105.6 Ex Cond 100 3100 1899.78 1910.06 1910.06 1910.81 0.00254 8.04 527.30 306.97 105.6 PrCond 100 E 3100 1899.78 1910.06 1910.06 1910.81 0.00254 8.04 527.30 306.97 105.35 Ex Cond 100 3100 1900.13 1907.48 1907.48 1909.21 0.00235 11.24 306.66 102.08 105.35 PrCond 100 E 3100 1900.13 1907.48 1907.48 1909.21 0.00235 11.24 306.66 102.08 104.1 Ex Cond 100 3100 1894.99 1903.21 1903.21 1904.85 0.00472 10.86 326.71 95.05 104.1 PrCond 100 E 3100 1894.99 1903.21 1903.21 1904.85 0.00472 10.86 326.71 95.05 102.9 Ex Cond 100 3100 1891.30 1899.60 1899.60 1901.12 0.00463 10.74 340.38 100.67 102.9 PrCond 100 E 3100 1891.30 1899.60 1899.60 1901.12 0.00463 10.74 340.38 100.67 102.45 Ex Cond 100 3100 1890.30 1898.83 1898.83 1899.96 0.00306 9.33 405.38 160.98 102.45 PrCond 100 E 3100 1890.30 1898.83 1898.83 1899.96 0.00306 9.33 405.38 160.98 101.9 Ex Cond 100 3100 1888.14 1897.55 1897.55 1898.60 0.00297 9.48 425.17 174.86 101.9 PrCond 100 E 3100 1888.14 1897.51 1897.51 1898.70 0.00325 9.88 381.26 135.21 101.3 Ex Cond 100 3100 1886.47 1895.32 1895.32 1896.29 0.00306 8.81 441.09 200.00 101.3 PrCond 100 E 3100 1886.47 1895.42 1895.42 1896.77 0.00371 9.79 344.16 113.64 100.85 Ex Cond 100 3100 1884.71 1894.44 1894.44 1895.41 0.00288 8.70 457.22 224.96 100.85 PrCond 100 E 3100 1884.71 1892.26 1892.26 1894.98 0.00848 13.25 234.07 45.10 100.7 PrCond 100 E 3100 1884.30 1891.78 1891.78 1894.76 0.00887 13.86 223.70 38.19 100.35 Ex Cond 100 3100 1883.36 1893.57 1893.57 1894.42 0.00238 8.62 496.44 258.64 100.35 PrCond 100 E 3100 1883.36 1892.12 1889.88 1893.56 0.00388 9.62 322.14 41.00 100.1 PrCond 100 E 3100 1882.00 1891.68 1888.92 1893.43 0.00411 10.62 291.95 30.22 99.9 Ex Cond 100 2400 1882.12 1892.36 1890.01 1892.78 0.00036 5.84 662.25 310.58 99.8 Winburn Way 99.35 PrCond 100 E 3100 1879.85 1889.70 1886.48 1891.22 0.00067 9.86 314.27 45.62 99.1 PrCond 100 E 3100 1879.80 1889.70 1886.44 1891.20 0.00066 9.81 316.69 39.33 98.6 Ex Cond 100 2400 1879.76 1891.41 1891.41 1892.73 0.00166 10.36 278.17 87.11 98.6 PrCond 100 E 3100 1879.76 1889.67 1886.41 1891.16 0.00064 9.79 320.88 48.24 98.55 PrCond 100 E 3100 1879.76 1890.16 1886.24 1891.10 0.00193 7.81 400.21 55.86 98.2 Ex Cond 100 2400 1878.21 1886.81 1886.81 1889.46 0.00544 13.09 187.37 39.38 98.2 PrCond 100 E 3100 1878.21 1888.04 1888.04 1890.82 0.00467 13.51 239.75 45.16 98.19 Ex Cond 100 2400 1877.69 1886.69 1886.69 1889.37 0.00477 13.17 185.71 38.54 98.19 PrCond 100 E 3100 1877.69 1887.94 1887.94 1890.75 0.00409 13.57 238.59 45.00 97.7 Ex Cond 100 2400 1875.52 1885.47 1883.70 1887.27 0.00333 10.76 224.46 31.47 97.7 PrCond 100 E 3100 1875.52 1884.50 1884.50 1887.54 0.00904 13.99 221.59 36.54 97.4 Ex Cond 100 2400 1876.97 1883.87 1883.87 1887.00 0.00580 14.25 172.65 30.35 97.4 PrCond 100 E 3100 1875.51 1882.68 1882.68 1885.39 0.00878 13.21 234.60 43.52 97.05 Ex Cond 100 2400 1874.62 1884.07 1884.07 1885.51 0.01012 10.06 254.18 76.58 97.05 PrCond 100 E 3100 1874.59 1881.89 1881.89 1884.72 0.00755 13.53 231.72 43.19 96.7 Ex Cond 100 2400 1873.46 1881.24 1881.24 1883.81 0.00522 13.27 207.67 44.05 96.7 PrCond 100 E 3100 1873.46 1881.48 1880.81 1883.85 0.00532 12.42 260.03 44.80 96.45 Ex Cond 100 2400 1872.47 1881.68 1880.46 1882.88 0.00234 9.12 296.34 66.97 96.45 PrCond 100 E 3100 1872.47 1882.58 1880.50 1883.64 0.00202 8.48 393.64 67.68 96.4 Ped. Bridge Table D-7: HEC-RAS Output, All Improvements HEC-RAS River: Ashland Cr Reach: River Sta Q Total Min Ch El W.S. Elev Crit W.S. E.G. Elev E.G. Slope Vel Chnl Flow Area Top Width Cross Section Condition da a ft a & ft& f}/sec ELA it 96.35 Ex Cond 100 2400 1873.24 1880.50 1880.50 1882.37 0.00373 11.36 244.11 69.01 96.35 PrCond 100 E 3100 1873.24 1882.46 1880.87 1883.51 0.00213 8.62 400.80 77.23 95.9 Ex Cond 100 2400 1871.16 1881.32 1881.95 0.00139 6.98 405.99 94.96 95.9 PrCond 100 E 3100 1871.16 1882.84 1879.53 1883.41 0.00093 6.40 544.99 81.24 95.65 Ex Cond 100 2400 1870.52 1881.33 1881.91 0.00132 6.70 416.16 81.04 95.65 PrCond 100 E 3100 1870.52 1882.78 1879.14 1883.38 0.00101 6.61 519.65 68.49 95.6 Ex Cond 100 2400 1870.52 1881.02 1881.87 0.00198 8.26 347.60 79.04 95.6 PrCond 100 E 3100 1870.52 1882.34 1879.75 1883.33 0.00176 8.51 407.98 57.16 95.4 Ex Cond 100 2400 1869.89 1879.80 1881.71 0.00480 11.64 226.97 43.08 95.4 PrCond 100 E 3100 1869.89 1881.19 1879.03 1883.18 0.00352 11.38 278.95 33.59 95.38 Ex Cond 100 2400 1869.89 1880.61 1881.61 0.00236 8.39 309.40 55.38 95.38 PrCond 100 E 3100 1869.89 1881.90 1878.55 1883.10 0.00201 8.84 359.12 42.38 94.7 Ex Cond 100 2400 1868.72 1880.50 1881.51 0.00107 6.09 333.06 50.31 94.7 PrCond 100 E 3100 1868.72 1881.78 1883.00 0.00103 6.41 398.04 51.63 94 Ex Cond 100 2400 1865.57 1880.73 1873.92 1881.42 0.00069 6.66 360.45 76.54 94 PrCond 100 E 3100 1865.57 1881.95 1875.04 1882.91 0.00085 7.85 394.68 96.69 93.6 Main Street Bridge 93.25 Ex Cond 100 2400 1864.79 1875.69 1872.12 1877.14 0.00216 9.67 248.20 92.97 93.25 PrCond 100 E 3100 1864.79 1873.36 1873.36 1877.39 0.00841 16.10 192.53 92.06 92.75 Ex Cond 100 3100 1863.45 1876.68 1877.00 0.00035 4.57 705.39 82.66 92.75 PrCond 100 E 3100 1863.45 1873.71 1874.43 0.00126 7.14 465.26 78.32 92.45 Ex Cond 100 3100 1861.59 1876.30 1876.95 0.00071 7.15 497.04 53.65 92.45 PrCond 100 E 3100 1861.59 1871.62 1871.62 1874.18 0.00487 14.16 257.06 46.98 92.3 Ex Cond 100 3100 1861.80 1876.43 1870.79 1876.92 0.00125 4.31 712.84 79.82 92.3 PrCond 100 E 3100 1861.80 1872.53 1873.51 0.00230 10.15 490.03 77.11 92.2 Ex Cond 100 3100 1861.80 1875.17 1870.30 1876.78 0.01055 11.63 396.04 43.03 92.2 PrCond 100 E 3100 1861.80 1871.50 1873.38 0.00469 13.48 361.71 53.21 92.05 Ex Cond 100 3100 1862.27 1874.11 1876.62 0.00266 12.70 244.79 22.03 92.05 PrCond 100 E 3100 1862.27 1871.94 1873.29 0.00213 9.75 341.90 47.96 91.76 Ex Cond 100 3100 1861.11 1876.20 1869.45 1876.37 0.00015 3.63 940.59 128.98 91.76 PrCond 100 E 3100 1861.11 1872.47 1869.45 1873.18 0.00097 7.11 486.44 107.62 91.72 Ped. Bridge 91.68 Ex Cond 100 3100 1861.11 1876.18 1876.35 0.00018 3.46 938.16 128.98 91.68 PrCond 100 E 3100 1861.11 1872.43 1873.13 0.00125 7.03 482.71 107.27 91.5 Ex Cond 100 3100 1860.76 1876.16 1876.34 0.00022 3.50 891.79 129.07 91.5 PrCond 100 E 3100 1860.76 1872.57 1873.09 0.00095 6.07 550.87 108.88 91.1 Ex Cond 100 3100 1859.88 1875.77 1872.67 1876.30 0.00033 6.74 571.56 100.96 91.1 PrCond 100 E 3100 1859.88 1871.75 1867.10 1873.00 0.00035 8.96 346.08 60.83 90.9 Lithia Way Culvert 90.7 Ex Cond 100 3100 1860.75 1873.75 1872.16 1874.11 0.00028 5.82 675.35 167.54 90.7 PrCond 100 E 3100 1860.75 1867.91 1867.91 1871.31 0.00164 14.79 209.57 38.62 90.35 Ex Cond 100 3100 1857.52 1868.45 1868.45 1873.61 0.00321 18.23 170.02 16.76 90.35 PrCond 100 E 3100 1857.52 1869.62 1865.10 1870.93 0.00053 9.17 340.64 38.35 90.1 Ex Cond 100 3100 1859.27 1868.75 1868.75 1876.28 0.01586 22.03 140.72 9.42 90.1 PrCond 100 E 3100 1859.27 1867.06 1867.06 1870.67 0.00524 15.24 203.45 28.34 89.45 Ex Cond 100 3100 1855.50 1864.97 1864.97 1867.04 0.00574 12.34 293.44 70.90 Table D-7: HEC-RAS Output, All Improvements HEC-RAS River: Ashland Cr Reach: River Sta Q Total Min Ch El W.S. Elev Crit W.S. E.G. Elev E.G. Slope Vel Chn1 Flow Area Top Width Cross Section Condition da ft a a ft a& ft/sec NA t. 89.45 PrCond 100 E 3100 1855.50 1865.29 1866.18 0.00204 7.93 441.16 91.39 88.8 Ex Cond 100 3100 1853.74 1863.61 1863.61 1865.83 0.00676 12.36 280.65 75.10 88.8 PrCond 100 E 3100 1853.74 1863.61 1863.61 1865.83 0.00676 12.36 280.65 75.10 88.4 Ex Cond 100 3100 1853.73 1864.09 1865.20 0.00257 9.01 419.14 132.66 88.4 PrCond 100 E 3100 1853.73 1862.74 1862.74 1864.96 0.00621 12.23 276.04 71.25 87.6 Ex Cond. 100 3100 1851.15 1864.82 1861.41 1865.05 0.00032 4.04 851.13 143.86 87.6 PrCond 100 E 3100 1851.15 1863.59 1858.99 1863.96 0.00058 5.03 680.02 132.04 87.5 Water Street Culvert 87.25 Ex Cond 100 3100 1849.2 1860.17 1860.17 1863.89 0.01091 15.48 200.29 27.08 87.25 PrCond 100 E 3100 1849.2 1861.36 1858.72 1862.10 0.00145 6.91 450.64 60.64 86.75 Ex Cond 100 3100 1849.24 1858.88 1858.88 1861.75 0.00675 14.46 263.17 50.59 86.75 PrCond 100 E 3100 1849.24 1858.88 1858.88 1861.75 0.00675 14.46 263.17 50.59 85.85 Ex Cond 100 3100 1844.03 1852.58 1852.58 1855.62 0.00744 14.44 230.26 38.53 85.85 PrCond 100 E 3100 1844.03 1852.58 1852.58 1855.62 0.00744 14.44 230.26 38.53 85.05 Ex Cond 100 3100 1843.87 1851.99 1851.99 1854.37 0.00582 12.71 281.81 73.63 85.05 PrCond 100 E 3100 1843.87 1851.99 1851.99 1854.37 0.00582 12.71 281.81 73.63 84.15 Ex Cond 100 3100 1842.52 1850.74 1850.74 1852.54 0.00697 13.46 334.85 91.88 84.15 PrCond 100 E 3100 1842.52 1850.74 1850.74 1852.54 0.00697 13.46 334.85 91.88 83.55 Ex Cond 100 3100 1840.48 1849.09 1849.09 1850.86 0.00546 11.66 360.40 103.73 83.55 PrCond 100 E 3100 1840.48 1849.09 1849.09 1850.86 0.00546 11.66 360.40 103.73 82.55 Ex Cond 100 3100 1838.31 1849.17 1850.03 0.00261 8.52 479.27 91.57 82.55 PrCond 100 E 3100 1838.31 1849.17 1850.03 0.00261 8.51 479.39 91.58 81.95 Ex Cond. 100 3100 1837.02 1849.70 1843.87 1849.92 0.00032 4.14 993.97 209.59 81.95 PrCond 100 E 3100 1837.02 1849.70 1843.87 1849.92 0.00032 4.14 994.18 209.59 81.9 Inline Weir 81.5 Ex Cond 100 3100 1835.52 1849.70 1844.86 1849.84 0.00027 3.56 1259.75 329.20 81.5 PrCond 100 E 3100 1835.52 1849.70 1844.86 1849.85 0.00027 3.56 1260.03 329.24 81.4 Van Ness Culvert 81.1 Ex Cond 100 3100 1835.37 1849.67 1844.48 1849.78 0.00026 3.44 1392.58 357.37 81.1 PrCond 100 E 3100 1835.37 1849.67 1844.48 1849.78 0.00026 3.44 1392.58 357.37 80.9 Ex Cond 100 3100 1834.04 1846.35 1843.95 1849.47 0.00294 14.18 218.67 229.58 80.9 PrCond 100 E 3100 1834.04 1846.35 1843.95 1849.47 0.00294 14.18 218.67 229.58 80.7 SPRR Culvert 80.5 Ex Cond 100 3100 1833.81 1843.53 1843.53 1848.21 0.00623 17.36 178.59 70.33 80.5 PrCond 100 E 3100 1833.81 1843.53 1843.53 1848.21 0.00623 17.36 178.59 70.33 80.15 Ex Cond 100 3100 1833.44 1842.21 1842.21 1843.12 0.00277 8.47 420.18 207.34 80.15 PrCond 100 E 3100 1833.44 1842.21 1842.21 1843.12 0.00277 8.47 420.18 207.34 80.14 Ex Cond 100 3100 1830.43 1842.17 1842.17 1843.09 0.00268 8.63 434.24 205.23 80.14 PrCond 100 E 3100 1830.43 1842.17 1842.17 1843.09 0.00268 8.63 434.24 205.23 79.05 Ex Cond 100 3100 1829.16 1836.14 1836.14 1837.14 0.00372 8.13 386.50 190.02 79.05 PrCond 100 E 3100 1829.16 1836.14 1836.14 1837.14 0.00372 8.13 386.50 190.02 78.4 Ex Cond 100 3100 1827.21 1834.82 1834.82 1835.67 0.00351 8.14 423.08 232.38 78.4 PrCond 100 E 3100 1827.21 1834.82 1834.82 1835.67 0.00351 8.14 423.08 232.38 77.5 Ex Cond 100 3100 1825.14 1832.67 1832.67 1833.90 0.00416 8.91 348.45 141.31 77.5 PrCond 100 E 3100 1825.14 1832.67 1832.67 1833.90 0.00416 8.91 348.45 141.31 Table D-7: HEC-RAS Output, All Improvements HEC-RAS River: Ashland Cr Reach: River Sta Q Total Min Ch El W.S. Elev Crit W.S. E.G. Elev E.G. Slope Vel Chnl Flow Area Top Width Cross Section Condition sfs ft ft $ $ &M SA-ft a 76.75 Ex Cond 100 3100 1823.25 1831.50 1831.50 1833.09 0.00476 10.39 308.15 93.86 76.75 PrCond 100 E 3100 1823.25 1831.50 1831.50 1833.09 0.00476 10.39 308.15 93.86 76 Ex Cond 100 3100 1821.58 1830.88 1831.32 0.00059 4.43 615.13 147.54 76 PrCond 100 E 3100 1821.58 1829.25 1830.09 0.00179 6.71 429.73 120.28 75.55 Ex Cond 100 3100 1819.08 1831.10 1828.68 1831.29 0.00035 4.22 931.51 260.72 75.55 PrCond 100 E 3100 1819.08 1829.73 1826.31 1830.00 0.00055 4.38 766.03 199.74 75.25 Hersey Street Bridge 74.9 Ex Cond 100 3100 1816.12 1827.49 1827.49 1828.84 0.00360 9.97 405.81 171.31 74.9 PrCond 100 E 3100 1816.12 1823.16 1823.16 1826.40 0.00995 14.43 214.78 33.01 73.8 Ex Cond 100 3100 1815.36 1822.36 1822.36 1823.29 0.00338 8.84 503.52 240.87 73.8 PrCond 100 E 3100 1815.36 1822.36 1822.36 1823.29 0.00338 8.84 503.52 240.87 * Existing Conditions - 100 Year Flow Event All Improvements - 100 Year Flow Event p:\...\7844\hydraul\dtablm.wk417d1 Appendix E - Existing and Proposed HEC-RAS Input Files APPENDIX E: EXISTING CONDITIONS HEC-RAS INPUT FILE 1 Geom Title=Ashland Creek. Ex Conditions CC Viewing Rectangle= 9.23244160149187E-02 , 0.725513440940151 , 0.876378545286175 , 0.243 1 89 5203 60943 River Reach=Ashland Cr rl Junct Up Dn= Reach XY= 2 .111731 .8652882 .705679 .2641931 Rch Text X Y=0.4124629,0.7205357 Reverse River Text= 0 Type RM Length L Ch R = 1 ,115.90 ,65,70,75 BEGIN DESCRIPTION: uppermost XS 115+90 END DESCRIPTION: #Sta/Elev= 12 33.7 1943.35 57.5 1940.8 841938.12 90.7 1934.65 93 1933.7 99 1933.35 103 1932.95 108 1933.48 110.5 1934.8 122 1938.68 129.5 1938.82 144 1944.1 #Mann= 3 ,-1 , 0 33.7 .045 0 90.7 .03 0 110.5 .045 0 Bank Sta=84,122 Exp/CnW=O. 1,0. 1 Type RM Length L Ch R = 1 ,115.20 ,10,10,10 BEGIN DESCRIPTION: 115+20 upstream bridge cross section END DESCRIPTION: #Sta/Elev= 14 201943.71 361938.99 711939.47 88.5 1933.35 901931.03 93 1930.41 97 1930.31 99.5 1931.32 104 1932.28 106 1932.87 111 1938.82 113.2 1939.25 135 1940.67 140 1945 #Mann= 4 ,-1 , 0 20 .025 0 71 .045 0 88.5 .03 0 106 .045 0 Bank Sta=71,113.2 Exp/Cntr--0.1,0.1 Type RM Length L Ch R = 3,115.15 BEGIN DESCRIPTION: CL footbridge at xs 115+15 END DESCRIPTION: Bridge Culvert--1,0,0,-1 Deck Dist Width WeirC Skew NumUp NumDn MinLoCord MaxHiCord MaxSubmerge Is-Ogee 2,6.2.6.,4,4,1939„0.95,0,0,0„ 65 70 117 122 1939 1940.38 1940.83 1939 1939 1939.22 1939.22 1939 65 70 117 122 1939 1940.38 1940.83 1939 1939 1939.22 1939.22 1939 BR Coef=-I , 0, 0- 0 ,,,0.8: 1„1, WSPro=,,,, 1 0.-0 ,,,,-1 ,-1 .-1 , 0, 0, 0, 0, 0 Type RM Length L Ch R = 1 ,115.10 ,40,35,30 BEGIN DESCRIPTION: 115+10 downstream xs for footbridge END DESCRIPTION: #Sta/Elev= 14 201943.71 361938.99 711939.47 88.5 1933.35 901931.03 93 1930.41 97 1930.31 99.5 1931.32 104 1932.28 106 1932.87 111 1938.82 113.2 1939.25 135 1940.67 140 1945 #Mann= 4,-1 , 0 20 .025 0 71 .045 0 88.5 .03 0 106 .045 0 Bank Sta=71.113.2 Exp/Cntr=O. 1,0. 1 Type RM Length L Ch R = 1 ,114.75 ,100,95,90 BEGIN DESCRIPTION: xs 114+75 END DESCRIPTION: #Sta/Elev= 15 6 1943 111938.17 321936.38 54.2 1936.64 87.8 1937.02 APPENDIX E: EXISTING CONDITIONS HEC-RAS INPUT FILE 2 94.5 1931.88 951929.95 991929.62 107.2 1930.13 1081931.85 112.2 1930.98 119 1933.47 123.3 1938.22 132 1938.43 143.2 1939.46 #Mann= 4 ,-1 , 0 6 .025 0 87.8 .045 0 94.5 .03 0 119 .045 0 Bank S ta=87.8,123.3 Exp/Cntr=O. 1,0. 1 Type RM Length L Ch R = 1 ,113.80 ,80,74,72 BEGIN DESCRIPTION: xs 113+80 END DESCRIPTION: #Sta/Elev= 15 -81936.42 101936.42 531934.62 56.2 1934.71 661934.61 70.5 1934.02 86.8 1932.13 881929.87 90.4 1929.11 941928.27 99.5 1927.52 106.8 1928.56 108 1930.02 121 1937.85 130.7 1937.92 #Mann= 4,-1 , 0 -8 .025 0 66 .045 0 88 .03 0 108 .045 0 #Block Obstruct= 1 ,-1 10 53 1937 Bank Sta=86.8,121 Exp/Cntr~. 1,0. 1 Type RM Length L Ch R = 1 ,113.06 81,8 1,81 BEGIN DESCRIPTION: xs113+06 END DESCRIPTION: #Sta/Elev= 17 -701936.47 -40 1932.9 401932.35 661932.48 84.1 1933.9 84.2 1931.55 90.5 1926.61 94.3 1926.54 97.4 1926.06 102.5 1926.76 107.3 1926.45 111 1927.51 115 1927.52 122 1933.9 123.2 1933.87 135 1935.51 147 1944.94 #Mann= 4,-1 , 0 -70 .025 0 84.2 .045 0 90.5 .03 0 123.2 .045 0 Bank Sta=84.1,122 Exp/Cntr=0. 1,0. 1 Type RM Length L Ch R = 1 ,112.25 ,50,50,45 BEGIN DESCRIPTION: xs 112+25 END DESCRIPTION: #Sta/Elev= 16 -1051936.99 -951934.52 -601931.82 -151931.08 58.5 1929.59 88.4 1928.32 90 1924.1 90.8 1923.17 97.4 1922.72 99.5 1921.89 106.8 1921.37 108.5 1921.66 109.2 1924.34 119 1931.17 136.5 1931.75 143.7 1935.86 #Mann= 3 .-1 , 0 -105 .025 0 90 .03 0 109.2 .045 0 Bank Sta=88.4,119 Exp/Cntr=0.1,0.1 Type RM Length L Ch R = l ,111.75* ,50,50,45 #Sta/Elev= 28 -108.99 1935.91 -98.73 1934.36 -62.81 1931.91 -37.8 1930.94 -16.64 1930.62 -16.351930.62 58.77 1928.17 59.71 1928.13 73.85 1928.67 89.45 1927.19 90.45 1924.81 90.95 1924.21 95.07 1922.89 96.39 1922.12 100.95 1920.65 104.1 1920.83 104.31 1921.04 105.4 1922.43 106.5 1922.9 108.55 1923.78 113.07 1925.04 118 1925.87 123.55 1928.61 141.3 1929.69 147.68 1929.85 151.04 1930 162.35 1932.45 165 1935 #Mann= 3 ,-1 , 0 -108.99 .025 0 89.45 .03 0 123.55 .045 0 Bank Sta=89.45,123.55 Exp/Cntr=0.1,0.1 Type Rol Length L Ch R = 1 ,111.25 ,15,15,15 BEGIN DESCRIPTION: upstream xs for bridge (111+25) END DESCRIPTION: #Sta/Elev= 17 -1131934.82 -401930.47 -181930.16 60 1926.7 74.5 1928.38 90.5 1926.05 95.1 1919.93 100 1920 103.2 1921.04 106.2 1922.03 APPENDIX E: EXISTING CONDITIONS HEC-RAS INPUT FILE 3 112.8 1922.86 120 1922.65 128.1 1926.06 152.3 1927.83 161 1928.03 181 1929.03 187 1935 #Mann= 6,-l , 0 -113 .025 0 -40 .013 0 60 .025 0 74.5 .045 0 95.1 .03 0 120 .045 0 Bank Sta=90.5,128.1 Exp/Cntr=O. 1,0. 1 Type RM Length L Ch R = 3,111.18 BEGIN DESCRIPTION: Maintenance Access Bridge END DESCRIPTION: Bridge Culvert--1,0,0,-1 Deck Dist Width WeirC Skew NumUp NumDn MinLoCord MaxHiCord MaxSubmerge Is-Ogee 1,12,2.6„2,2,1926.7„0.95,0,0,0„ 77 160 1930 1930 1928 1928 77 160 1930 1930 1928 1928 BR Coef= 1 , 0, 0, 0 ,,,0.8,-T„1, WSPro=,,,, 1 0 0 ,-1 ,-1 , 0, 0, 0, 0, 0 Type RM Length L Ch R = 1 ,111.10 ,40,27,15 BEGIN DESCRIPTION: downstream xs for bridge (111+10) END DESCRIPTION: #Sta/Elev= 15 -1181934.02 -281929.47 -101929.34 581926.44 931925.66 95.6 1920.77 100.8 1919.18 104.8 1919.63 113.2 1921.86 122 1923.22 130.6 1926.77 144.2 1927.83 161 1928 181 1929 186 1935 #Mann= 6 ,-1 , 0 -118 .025 0 -28 .013 0 58 .025 0 93 .045 0 95.6 .03 0 122 .045 0 Bank Sta=93,130.6 Exp/Cntr=0.1,0.1 Type RM Length L Ch R = 1 ,110.83 ,50,73,80 BEGIN DESCRIP'T'ION: xs110+83 END DESCRIP'T'ION: #Sta/Elev= 12 -20 1928 -101926.26 60 1924 901920.46 96.5 1920.46 100.4 1920.41 105 1920.39 112.7 1920.57 116.4 1921.72 122 1925.46 156.5 1926.03 166 1928 #Mann= 3 ,-1 , 0 -20 .013 0 60 .025 0 116.4 .045 0 Bank Sta=60,122 Exp/Cntr=0.1,0.1 Type RMLength LChR=1,110.10 ,1,1,1 BEGIN DESCRIPTION: xs for filled weir @ 110+10 END DESCRIPTION: #Sta/Elev= 10 -95 1926.7 0 1924.5 60 1923 75 1922 89.6 1921.02 97.4 1921.06 115.4 1921.1 119.5 1921.75 147.3 1923.9 155 1926.81 #Mann= 4,-1 , 0 -95 .025 0 0 .013 0 60 .025 0 1195 .045 0 Bank Sta=75,119.5 Exp/Cntr=0.1,0.1 Type RM Length L Ch R = 1 ,110.09 .20,14,5 BEGIN DESCRIPTION: ds for filled weir (110+09) END DESCRIPTION: #Sta/Elev= 11 -90 1926.7 0 1924.5 60 1923 75 1922 89.6 1921.02 95 1916.29 108 1915.85 115.2 1915.83 115.3 1921.1 119.5 1921.75 155 1926.81 #Mann= 4A , 0 APPENDIX E: EXISTING CONDITIONS HEC-RAS INPUT FILE 4 -90 .025 0 0 .013 0 60 .025 0 115.3 .045 0 Bank Sta=75,119.5 Exp/Cntr=O. 1,0. 1 Type RM Length L Ch R = 1 ,109.95 ,50,50,45 BEGIN DESCRIPTION: xs 109+95 END DESCRIPTION: #Sta/Elev= 14 -90 1924.8 51923.75 67 1922 88.2 1921.91 89.4 1919.22 94.5 1918.15 100.2 1917.43 105 1917.23 108.2 1916.77 109.5 1916.78 116 1917.49 122.4 1922.28 146.8 1923.9 153.1 1926.81 #Mann= 4 ,-1 , 0 -90 .025 0 5 .013 0 67 .03 0 116 .045 0 Bank Sta=88.2,122.4 Exp/Cntr=O. 1,0. 1 Type RM Length L Ch R = 1 ,109.45 ,1,1,1 BEGIN DESCRIPTION: xs for concrete weir (109+45) END DESCRIPTION: #Sta/Elev= 9 -95 1923.5 14.5 1921.2 65 1921.5 841918.03 101.4 1917.82 108.7 1917.84 121 1920.9 137 1920.54 147 1930 #Mann= 4 ,-1 , 0 -95 .025 0 14.5 .013 0 65 .03 0 121 .045 0 Bank Sta=65,121 Exp/Cntr=0.1,0.1 Type RM Length L Ch R = 1 ,109.44 ,20,19,15 BEGIN DESCRIPTION: d/s xs for concrete weir (109+44) END DESCRIPTION: #Sta/Elev= 9 -95 1923.5 14.5 1921.2 65 1921.5 841912.08 101.4 1911.87 108.7 1912.89 121 1920.9 137 1920.54 147 1925 #Mann= 4 ,-1 , 0 -95 .025 0 14.5 .013 0 65 .03 0 121 .045 0 Bank Sta=65,121 Exp/Cntr=O. 1,0. 1 Type RM Length L Ch R = 1 ,109.25 ,75,75,75 BEGIN DESCRIPTION: xs109+25 END DESCRIPTION: #Sta/Elev= 12 -85 1923 251920.19 67.8 1921.03 82.6 1914.2 85.1 1913.07 93.4 1912.07 109.1 1911.15 111.2 1912.9 111.5 1914.54 120 1920.9 135 1920.54 137 1921.89 #Mann= 5 ,-1 , 0 -85 .025 0 25 .013 0 67.8 .025 0 82.6 .03 0 120 .045 0 Bank Sta=67.8,120 Exp/Cntr=0.1,0.1 Type RM Length L Ch R = 1 ,108.50 ,65,65,70 BEGIN DESCRIPTION: xs 108+50 END DESCRIP'T'ION: #Sta/Elev= 14 -501923.27 -351918.55 251917.98 451918.64 71.6 1918.46 80.5 1917.99 90.1 1910.16 91.8 1907.99 94.8 1907.11 1001908.27 104.1 1908.79 109.2 1909.9 131.2 1920.01 143.1 1919.86 #Mann= 5 ,-1 , 0 -50 .025 0 25 .013 0 71.6 .03 0 109.2 .045 0 131.2 .025 0 Bank Sta=80.5,131? Exp/Cntr=0.1,0.1 APPENDIX E: EXISTING CONDITIONS HEC-RAS INPUT FILE 5 Type RM Length L Ch R = 1 ,107.85 ,85,85,85 BEGIN DESCRIPTION: xs 107+85 END DESCRIPTION: #Sta/Elev= 19 -30 1923 101917.27 201916.49 43.4 1916.51 71.5 1915.99 75.5 1916.05 83.9 1915.34 92.9 1907.92 971906.41 1001906.56 106.8 1905.8 108.5 1907.9 110 1907.95 118.5 1911.82 122.7 1913.08 146 1914.63 147 1917.05 160 1917.19 170 1923 #Mann= 4 ,-1 , 0 -30 .013 0 71.5 .03 0 122.7 .025 0 160 .045 0 Bank Sta=83.9,122.7 Exp/Cntr=0.1,0.1 Type RM Length L Ch R = 1 ,107.00 ,40,41.67,43.33 BEGIN DESCRIPTION: xs 107+00 END DESCRIP'T'ION: #Sta/Elev= 18 -50.1 1920 -50 1910 231913.36 491913.37 78.4 1912.65 83.1 1912.67 87.1 1912.18 92.8 1905.09 941904.41 100.4 1903.35 105.2 1903.7 108.3 1905.16 111.5 1905.5 114.8 1905.58 118.7 1911.97 1431911.83 184 1912.5 2111920.25 #Mann= 5 ,-1 , 0 -50.1 .025 0 23 .013 0 83.1 .03 0 118.7 .025 0 184 .045 0 Bank Sta=87.1,118.7 Exp/Cntr--O. 1,0. 1 Type RM Length L Ch R = 1 ,106.583*,40,41.67,43.33 #Sta/Elev= 30 -58.39 1917.6 -58.29 1910.82 -57.45 1909.94 16.97 1912.1 17.05 1912.1 43.78 1912.15 50.06 1912.05 72.88 1911.95 74.1 1911.87 78.94 1911.65 83.07 1911.11 90.17 1904.69 91.66 1903.88 95.62 1902.58 99.63 1902.12 103.68 1902.4 104.85 1902.55 108.22 1903.8 108.25 1903.8 110.75 1904.17 111.7 1904.43 115.29 1905.23 119.53 1910.36 131.91 1910.5 137.11 1910.62 148.27 1910.68 154.15 1910.78 196.74 1911.36 215.67 1914.51 228.67 1918.83 #Mann= 5 ,-1 , 0 -58.39 .021 0 16.97 .013 0 74.1 .03 0 83.07 .025 0 215.67 .045 0 Bank Sta=83.07,119.53 Exp/Cntr-0.1,0.1 Type RM Length L Ch R = 1 ,106.166*,40,41.67,43.33 #Sta/Elev= 30 -66.69 1915.19 -66.58 1911.64 -65.72 1909.85 10.95 1910.85 11.02 1910.85 38.56 1910.92 45.03 1910.89 68.54 1911.23 69.79 1911.1 74.78 1910.62 79.03 1910.05 87531904.29 89.32 1903.35 94.06190128 98.87 1900.98 103.24 1901.19 104.51 1901.4 108.15 1902.44 108.17 1902.45 110.87 1902.94 111.91 1903.37 115.78 1904.87 120.37 1908.75 134.66 1909.08 140.66 1909.35 153.53 1909.53 160.33 1909.66 209.49 1910.22 231.34 1911.92 246.33 1917.41 #Mann= 5 ,-1 , 0 -66.69 .017 0 10.95 .013 0 68.54 .024 0 79.03 .025 0 231.34 .045 0 Bank Sta=79.03,120.37 Exp/Cntr--0.1,0.1 Type RM Length L Ch R = 1 ,105.75 ,15,15,15 BEGIN DESCRIPTION: 105+75 us of bridge END DESCRIPTION: #Sta/Elev= 17 -75 1912.79 -74 1909.75 5 1909.59 40 1909.72 64.2 1910.5 751908.98 92.5 1899.98 98.1 1899.65 102.8 1899.97 108.1 1901.09 111 1901.71 121.2 1907.14 137.4 1907.67 144.2 1908.09 166.5 1908.53 2471909.33 2641915.99 #Mann= 4,-1 , 0 -75 .013 0 64.2 .03 0 121.2 .025 0 247 .045 0 Bank Sta=75.121.2 Exp/Cntr=0.1.0.1 APPENDIX E: EXISTING CONDITIONS HEC-RAS INPUT FILE 6 Type RM Length L Ch R = 2,105.70 BEGIN DESCRIPTION: Memorial Atkinson Culvert END DESCRIPTION: Bridge Culvert--1,0,0,-1 Deck Dist Width WeirC Skew NumUp NumDn MinLoCord MaxHiCord MaxSubmerge Is-Ogee 3,10,2.6„4,4,1908„0.95,0,0,0„ 76 90 110 122 1908.25 1910.15 1910.19 1908.25 0 0 0 0 76 90 110 122 1908.25 1910.15 1910.19 1908.25 0 0 0 0 BR Coef=-1 , 1 , 0,1, 0 ,,,0.8,0,1,0, WSPro=,,,, 1 0 0 ,-1 ,-1 , 0, 0, 0, 0, 0 Culvert=7,7.41,20,10,0.013,0.5,1,41,1,1899.65,100,1900.12,100,Culvert #1 , 0 ,2 Type RM Length L Ch R = 1 ,105.60 ,25,25,25 BEGIN DESCRIPTION: 105+60 ds of bridge END DESCRIP'T'ION: #Sta/Elev= 17 -751912.79 -741909.75 51909.59 401909.72 64.2 1910.5 751908.46 87.5 1904.72 901901.44 931900.68 1001900.12 107.2 1899.78 109.5 1901.75 110.8 1908.37 123.5 1907.1 166.5 1908.53 2471909.33 2641915.99 #Mann= 4 ,-1 , 0 -75 .013 0 64.2 .03 0 110.8 .025 0 247 .045 0 Bank Sta=75,110.8 Exp/Cntr=0.1,0.1 Type RM Length L Ch R = 1 ,105.35 ,125,125,125 BEGIN DESCRIPTION: XS 105+35 END DESCRIPTION: #Sta/Elev= 21 -551912.82 -541909.75 -201909.65 0 1909.1 171907.63 66.8 1907.58 721907.62 81.3 1906.97 91.2 1901.1 941900.38 100 1900.13 105.5 1900.13 112.3 1900.39 114.3 1900.87 118 1904.33 139.9 1904.98 1521906.93 1821907.62 2191908.05 2541908.73 269 1911.88 #Mann= 5 ,-1 , 0 -55 .013 0 72 .03 0 91.2 .015 0 139.9 .025 0 254 .045 0 Bank Sta=81.3,118 Exp/Cntr=0.1,0.1 Type RM Length L Ch R = 1 ,104.10 ,110.120.130 BEGIN DESCRIPTION: xs 104+10 END DESCRIPTION: #Sta/Elev= 18 151903.66 381903.94 671903.33 72.2 1903.41 77.9 1903.79 781903.64 84.1 1902.65 901896.89 97.1 1895.69 99.8 1895.66 110 1894.99 115.1 1896.42 123.2 1900.95 165 1902.09 175 1902.35 1761903.55 255 1905.6 265 1915 #Mann= 4 ,-1 , 0 15 .013 0 78 .03 0 123.2 .025 0 255 .045 0 Bank Sta=84.1,123.2 Exp/Cntr=0.1,0.1 Type FiM Length L Ch R = 1 ,102.90 ,45,45,40 BEGIN DESCRIPTION: xs 102+90 END DESCRIPTION: #Sta/Elev= 18 25 1899.95 46.9 1900.23 74.2 1899.64 78 1899.73 80.3 1899.58 86.8 1893.02 96.5 1892.18 1001891.82 106 1891.3 111.2 1892.85 115.8 1896.4 138.7 1897.65 165 1898.48 180 1898.74 181 1899.94 215 1902.73 280 1903.3 290 1913 #Mann= 4 ,-1 , 0 APPENDIX E: EXISTING CONDITIONS HEC-RAS INPUT FILE 7 25 .013 0 80.3 .03 0 115.8 .025 0 280 .045 0 Bank Sta=80.3,115.8 ExpiCntr=0.1,0.1 Type RM Length L Ch R = 1 ,102.45 ,60,55,50 BEGIN DESCRIP'T'ION: xs 102+45 END DESCRIPTION: #Sta/Elev= 19 25 1901 261898.35 541898.51 771898.16 84.9 1897.91 87.2 1893.77 90.5 1892.13 95.4 1890.83 1001890.48 109.2 1890.74 115 1890.3 121.4 1895.75 146 1896.66 166 1897.83 186 1897.86 1871899.06 2231901.99 285 1902.8 295 1912 #Mann= 4 ,-1 , 0 25 .013 0 84.9 .03 0 121.4 .025 0 285 .045 0 Bank Sta=84.9,121.4 Exp/Cntr=0.1,0.1 Type RM Length L Ch R = 1 ,101.90 ,55,60,65 BEGIN DESCRIPTION: xs 101+90 near missing footbridge END DESCRIPTION: #Sta/Elev= 20 29 1901 30 1896.6 51.5 1896.56 68.9 1895.93 79.2 1896.13 841895.96 85.5 1894.66 91.1 1890.08 97.3 1888.44 106.1 1888.14 107 1890.32 112.1 1894.29 126.1 1895.25 152 1895.45 185 1896.64 1951896.65 248 1901.6 2631901.81 280 1902 290 1912 #Mann= 4 ,-1 , 0 29 .013 0 85.5 .03 0 107 .025 0 280 .045 0 Bank Sta=84,112.1 Exp/Cntt=0.1,0.1 Type RM Length L Ch R = 1 ,101.30 ,40,45,50 BEGIN DESCRIPTION: xs101+30 END DESCRIPTION: #Sta/Elev= 16 20 1896 211894.41 571894.24 731893.84 74.6 1893.79 80.2 1893.98 931887.48 93.2 1887.42 96.7 1886.67 1001886.47 104.6 1886.64 110.8 1887.59 118 1894 1411893.52 2141894.53 237 1897.34 #Mann= 3 ,-1 , 0 20 .013 0 80.2 .03 0 118 .025 0 Bank Sta=80.2,118 Exp/Cntr-0.1,0.1 Type R.M Length L Ch R = 1 ,100.85 ,50,50,55 BEGIN DESCRIPTION: xs 100+85 END DESCRIPTION: #Sta/Elev= 13 30 1895 311893.53 521893.33 68.1 1892.6 881891.52 92 1885.74 102.4 1884.71 107.5 1885.77 115 1894 131 1892.13 1581892.93 2481893.97 2971897.11 #Mann= 3 ,-1 , 0 30 .013 0 88 .03 0 115 .025 0 Bank Sta=88,115 Exp/Cntr=0.1,0.1 Type RM Length L Ch R = 1 ,100.35 ,35,45,60 BEGIN DESCRIPTION: xs 100+35 END DESCRIP'T'ION: #Sta/Elev= 15 01893.55 451892.02 601892.82 80.1 1891.03 85.2 1890.11 100 1883.36 107.8 1883.97 115 1890.03 135.6 1891.58 166 1892.37 1881892.41 2051892.82 2581893.51 2801895.65 2891898.32 #Mann= 3 ,-1 , 0 0 .013 0 80.1 .03 0 135.6 .025 0 Bank Sta=85.2,115 APPENDIX E: EXISTING CONDITIONS HEC-RAS INPUT FILE 8 Exp/Cntr=O. 1,0. 1 Type RM Length L Ch R = 1 99.90 ,135,130,125 BEGIN DESCRIPTION: xs at us windburn way (99+90) END DESCRIPTION: #Sta/Elev= 20 2 1895 31892.95 361891.65 47.5 1891.5 76.5 1888.83 901882.45 981882.12 105.2 1882.26 110.8 1884.53 115 1890.6 1381889.92 1761890.95 2031891.14 2351891.81 2861891.24 3011891.29 3211891.35 341 1894 364 1896.1 3701901.28 #Mann= 3 ,-1 , 0 2 .013 0 76.5 .018 0 115 .025 0 #XS Ineff= 2 , 0 0 90 1890 115 0 1891 Bank Sta=76.5,115 Exp/Cntr=0.1,0.1 Type RM Length L Ch R = 3,99.8 BEGIN DESCRIPTION: Winburn Way END DESCRIPTION: Bridge Culvert--1,0,0,-1 Deck Dist Width WeirC Skew NumUp NumDn MinLoCord MaxHiCord MaxSubmerge Is-Ogee 3,125,2.6„17,3,1890.2„0.95,0,0,0„ 45 77 89 89.5 89.9 90.92 92.57 95.16 99.39 103.18 105.66 107.55 109.16 109.6 112 112.1 140 1891.5 1890.1 1890.1 1890.1 1893.19 1893.19 1893.19 1893.19 1893.19 1893.19 1893.19 1893.19 1893.19 1893.19 1893.19 1890.1 1890.1 0 0 0 01884.85 18861886.97 1887.9 1888.36 1888.04 1887.3 1886.28 1884.75 0 0 0 0 92 100 107 1891.42 1891.65 1891.5 1887 1887 1887 BR Coef=-1 , 1 , 0,1, 0 ,,,0.8,0,1,0, WSPro=,,,, 1 0 0 1-1 1-1 , 0 , 0 , 0, 0, 0 Type RM Length L Ch R = 1 98.60 ,45,40,40 BEGIN DESCRIPTION: xs d/s of winburn culvert (98+60) END DESCRIPTION: #Sta/Elev= 12 301895.96 311891.01 45 1890.1 551889.47 631889.47 801889.57 941889.57 94.1 1879.76 1071880.27 107.1 1888.83 118 1888.8 118.1 1897 #Mann= 3 ,-1 , 0 30 .013 0 94.1 .018 0 107.1 .013 0 #XS Ineff= 2 , 0 0 941889.57 107.1 01888.83 Bank Sta=94,107.1 Exp/Cntr-0.1,0.1 Type RM Length L Ch R = 1 98.20 ,1,1,1 BEGIN DESCRIPTION: xs 98+20 ds of windburn way conc. weir END DESCRIPTION: #Sta/Elev= 15 59 1896 601890.55 68.7 1890.17 69.4 1890.13 741887.33 831885.44 92.9 1879.66 93.5 1878.21 1021879.09 110.4 1881.54 114 1885.9 118 1887.89 136.4 1887.83 155 1887.62 155.1 1896 #Mann= 5 ,-1 , 0 59 .03 0 83 .018 0 92.9 .03 0 110.4 .018 0 114 .013 0 Bank Sta=83,114 Exp/Cntr-0.1,0. I Type RM Length L Ch R = 1 98.19 ,49,49,49 BEGIN DESCRIPTION: xs 98+19 ds of windburn way conc. weir END DESCRIPTION: #Sta/Elev= 15 59 1896 601890.55 68.7 1890.17 69.4 1890.13 741887.33 831885.44 931879.69 93.5 1878.21 1021877.69 1051879.21 APPENDIX E: EXISTING CONDITIONS HEC-RAS INPUT FILE 9 114 1885.9 118 1887.89 136.4 1887.83 155 1887.62 155.1 1896 #Mann= 5 ,-1 , 0 59 .03 0 83 .018 0 93 .03 0 105 .018 0 114 .013 0 Bank Sta=83,114 Exp/Cnir---O. 1,0. 1 Type RM Length L Ch R. = 1 97.70 ,35,30,30 BEGIN DESCRIPTION: xs 97+70 END DESCRIPTION: #Sta/Elev= 20 67.4 1892.68 67.5 1886.68 821887.06 831885.19 84.5 1883.89 911877.11 93.1 1876.23 93.3 1877.54 95.4 1875.52 1001875.62 104.8 1876.4 107 1876.35 108 1877.1 111.3 1879.1 113.4 1884.78 115.7 1886.51 126 1885.95 140 1886 155 1887.09 155.1 1895 #Mann= 5 ,-1 , 0 67.4 .03 0 84.5 .018 0 91 .03 0 111.3 .018 0 113.4 .013 0 Bank Sta=84.5,113.4 Exp/Cntr=O. 1,0. 1 Type RM Length L Ch R = 1 97.40 ,35,35,40 BEGIN DESCRIPTION: xs 97+40 upstream side of deck END DESCRIP'T'ION: #Sta/Elev= 17 541888.55 54.1 1884.5 591884.47 71.1 1885.23 81.8 1882.04 82.9 1882.16 90.1 1876.85 90.5 1876.83 92.1 1875.51 961875.57 100 1875.81 106.1 1876.99 109 1883.99 122 1884.81 138 1884.81 162 1885.07 162.1 1895 #Mann= 5 ,-1 , 0 54 .03 0 81.8 .018 0 82.9 .03 0 109 .018 0 122 .13 0 #XS Lid=4 106 1887.57 1883.1 109 1887.54 1883.1 114.9 1887.54 1883.1 115 1884 1883.1 Bank Sta=81.8,109 Exp/Cntr=0. 1,0. 1 Type RM Length L Ch R = 1 97.05 ,35,35,30 BEGIN DESCRIPTION: xs 97+05 ds of deck END DESCRIPTION: #Sta/Elev= 13 50 1888 59 1884 82.5 1880.63 95.6 1874.59 102.6 1874.73 106 1875.08 110.5 1875.74 110.6 1883.92 118 1883.24 122 1883.51 135 1883.36 149 1883.28 149.1 1893 #Mann= 4 .-1 , 0 50 .03 0 82.5 .018 0 95.6 .03 0 110.5 .013 0 #XS Lid=3 97 1887.59 1881.6 110.5 1887.59 1881.6 110.6 1883.92 1881.6 Bank Sta=82.5,110.6 Exp/Cntr=O. 1,0. 1 Type RM Length L Ch R = 1 96.70 ,25,25,25 BEGIN DESCRIPTION: xs 96+70 END DESCRIPTION: #Sta/Elev= 14 46 1888 56.4 1884.15 73.2 1878.42 821877.94 92.5 1874.98 97.3 1873.46 103 1873.79 106.2 1874.01 108.9 1875.04 109 1882.35 136 1882.5 136.1 1886.11 145 1886.11 145.1 1890 #Mann= 4,-l .0 46 .045 0 82 .018 0 92.5 .03 0 108.9 .013 0 Bank Sta=82.109 Exp/Cntr=0.1,0.1 Type RM Length L Ch R = 1 96.45 ,10,10,10 BEGIN DESCRIPTION: us of bridge (xs 96+45) APPENDIX E: EXISTING CONDITIONS HEC-RAS INPUT FILE 10 END DESCRIPTION: #Sta/Elev= 14 471882.93 551879.85 801879.55 85.2 1873.92 96.3 1873.42 104.2 1872.47 107 1874.34 109.5 1875.65 115.5 1881.43 115.6 1882.21 126.2 1882.9 135 1881.76 138 1881.58 138.1 1887 #Mann= 5 ,-1 , 0 47 .03 0 80 .018 0 85.2 .03 0 109.5 .018 0 115.5 .013 0 Bank Sta=80,115.5 Exp/Cnv--O.1,0.1 Type RM Length L Ch R = 3,96.40 BEGIN DESCRIPTION: Calle G. Bridge END DESCRIPTION: Bridge Culvert--1,0,-1,-1 Deck Dist Width WeirC Skew NumUp NumDn MinLoCord MaxHiCord MaxSubmerge Is-Ogee 2,6,2.6„5,5,1878.3„0.95,0,0,0„ 81.5 81.6 98 114 114.1 1882.6 1882.6 1885.3 1885 1885 0 1878.3 1881.02 1880.66 0 81.5 81.6 98 116 116.1 1882.6 1882.6 1885.3 1885 1885 0 1878.3 1881.02 1880.66 0 BR Coef=-I , 0, 0, 0 ,,,0.8,-1„l, WSPro=,.,, 1 0 0 ,-1 ,-1 , 0, 0, 0, 0, 0 Type RM Length L Ch R = 1 96.35 ,40,45,50 BEGIN DESCRIPTION: ds of bridge (xs 96+35) END DESCRIPTION: #Sta/Elev= 14 391882.58 501879.67 671879.35 81.51 1877.33 83.7 1875.39 94.8 1873.97 96.9 1873.24 103.1 1873.24 108.8 1874.13 116.7 1881.25 121 1881.05 126 1881.35 136 1881.58 136.1 1885 #Mann= 5 ,-1 , 0 39 .03 0 83.7 .018 0 94.8 .03 0 108.8 .018 0 116.7 .013 0 Bank Sta=81.51,116.7 Exp/Cntr=O. 1,0. 1 Type RM Length L Ch R = 1 95.90 ,20,25,25 BEGIN DESCRIPTION: xs 95+90 END DESCRIPTION: #Sta/Elev= 19 35 1882.6 451878.44 54.8 1878.38 61.5 1878.01 81.2 1877.41 92.1 1872.92 96.5 1872.13 1001871.61 102.7 1871.16 106.8 1871.99 108.2 1873 110.1 1878.26 110.8 1878.2 115.5 1878.81 116 1879.32 133 1879.75 133.1 1883.27 140 1883.27 140.1 1885 #Mann= 4,1 , 0 35 .03 0 81.2 .03 0 108.2 .018 0 110.1 .013 0 Bank Sta=81.2,110.1 Exp/Cntr=0.1,0.1 Type RM Length L Ch R = 1 95.65 ,5,5,5 BEGIN DESCRIPTION: xs 95+65 END DESCRIPTION: #Sta/Elev= 15 51 1880.68 56 1876.81 62 1877.27 69.7 1877.75 76 1877.75 88.5 1876.6 91.8 1872.06 93.1 1870.52 97.6 1871.1 105.2 1870.53 107.3 1871.92 117.2 1877.91 117.4 1880.38 132 1878.91 132.1 1885 #Mann= 2 ,-1 , 0 51 .03 0 117.2 .013 0 Bank Sta=88.5,117.4 Exp/Cntr=0.1,0.1 Type RBI Length L Ch R = 1 95.60 ,25,20.15 BEGIN DESCRIPTION: xs 95+60 END DESCRIPTION: APPENDIX E: EXISTING CONDITIONS HEC-RAS INPUT FILE 11 #Sta/Elev= 14 551880.68 621876.81 671877.27 74.5 1877.75 801877.75 891876.46 911872.06 93.1 1870.52 97.6 1871.1 109.2 1871.85 110 1873.4 110.5 1880.65 134 1878.58 134.1 1885 #Mann= 2 ,-1 , 0 55 .03 0 110 .013 0 Bank Sta=89,110.5 Exp/Cntr=O. 1,0. 1 Type RM Length L Ch R = 1 95.40 ,2,2,2 BEGIN DESCRIPTION: xs 95+40 END DESCRIPTION: #Sta/Elev= 14 70 1886 80.2 1876.94 85.2 1876.45 90.1 1876.39 90.3 1869.92 95 1870.25 100 1870 106.7 1869.89 107 1871.81 108 1872.16 109 1880.26 117 1880.74 132 1877.16 132.1 1885 #Mann= 2 ,-1 , 0 70 .03 0 108 .013 0 Bank Sta=90.1,109 ExpiCntr=O. 1,0. 1 Type RM Length L Ch R = 1 95.38 ,75,68,60 BEGIN DESCRIPTION: xs 95+38 END DESCRIPTION: #Sta/Elev= 14 70 1886 80.2 1876.94 85.2 1876.45 90.1 1876.39 90.3 1869.92 95 1870.25 100 1870 106.7 1869.89 107 1871.81 108 1872.16 116 1876.93 117 1880.74 132 1877.16 132.1 1890 #Mann= 2 ,-1 , 0 70 .03 0 116 .013 0 Bank Sta=90.1,117 Exp/Cntr=O. 1,0. 1 Type RM Length L Ch R = 1 94.70 ,85,70,60 BEGIN DESCRIPTION: xs 94+70 END DESCRIPTION: #Sta/Elev= 10 75 1888 85 1878.3 91.2 1878.31 91.5 1870.52 97.9 1868.72 102.4 1869.77 109 1869.32 109.5 1875.03 133 1875.92 133.1 1890 #Mann= 2 ,-1 , 0 75 .03 0 109 .013 0 Bank Sta=91.2,109.5 Exp/Cntr--O. 1,0. 1 Type ILM Length L Ch R = 1 94.00 ,75,75,75 BEGIN DESCRIPTION: xs 94+00 us of main street culvert END DESCRIPTION: #Sta/Elev= 14 62 1884 65 1881 75.1 1881.74 75.2 1869.19 91.2 1868.22 95.1 1865.87 97.8 1865.57 1031866.82 109.3 1866.99 110.1 1870.01 116.5 1871.6 126.1 1877.28 161 1881.99 165 1884 #Mann= 4 ,-1 , 0 62 .03 0 65 .013 0 75.2 .03 0 116.5 .018 0 #XS Ineff= 2, 0 0 89.1 1883 117 0 1883 Bank Sta=75.1,126.1 Exp/Cntr=O. 1,0. 1 Type RM Length L Ch R = 3,93.60 BEGIN DESCRIPTION: :Main Street Bridge END DESCRIPTION: Bridge Culvert--1.0,-1,-1 Deck Dist Width WeirC Skew NumUp NumDn MinLoCord MaxHiCord MaxSubmerge Is-Ogee 13.50 2.6„9,9,1883„0.95,0,0,0„ 75 89 89.1 96.2 102 108.7 117 117.1 161 1881.74 1882.17 1882.17 1882.2 1882.2 1882.15 1882.23 1882.23 1882 0 0 1871.92 1874.09 1874,93 1874.18 1871.6 0 0 APPENDIX E: EXISTING CONDITIONS HEC-RAS INPUT FILE 12 0 85 85.1 95 100 105 109 109.1 150 1881.74 1882 1882 1882 1882.2 1882.2 1882.15 1882.15 1880.59 0 0 1870.02 1872.61 1872.93 1872.08 1870.27 0 0 BR Coef=-1 , 1 , 0,1, 0 ,,,0.8,0,1,0, WSpro=,,,, 1 0 0 1 ,-1 ,-1 , 0 , 0 , 0 , 0 , 0 Type RM Length L Ch R. = 1 93.25 ,30,50,70 BEGIN DESCRIPTION: xs 93+25 ds of main street culvert END DESCRIPTION: #Sta/Elev= 15 35 1885 35.1 1869.87 631869.64 81 1869.6 821867.47 85 1866.4 85.5 1865.97 981864.95 1031864.79 1081865.08 108.5 1866.34 109 1870.72 126 1870.43 130 1880.79 150 1880.59 #Mann= 4 ,-1 , 0 35 .03 0 81 .025 0 82 .03 0 109 .025 0 #XS Ineff= 2, 0 0 85.1 1879 109 0 1879 Bank Sta=81,109 Exp/Cntr=O.1,0.1 Type RM Length L Ch R = 1 92.75 ,25,30,30 BEGIN DESCRIPTION: xs 92+75 bluebird deck area END DESCRIPTION: #Sta/Elev= 15 73 1885 73.1 1869.42 851869.42 85.1 1867.15 871866.53 931864.59 961863.79 103.5 1863.45 1081864.92 1121868.36 123 1868.43 129 1868.37 145 1869.84 155 1875.89 156 1877 #Mann= 3 ,-1 , 0 73 .013 0 85.1 .03 0 112 .025 0 Bank Sta=85.1,112 Exp/Cntr=O.1,0.1 Type RM Length L Ch R = 1 92.45 ,15,15,15 BEGIN DESCRIPTION: 92+45 area with food deck END DESCRIPTION: #Sta/Elev= 14 91 1885 91.1 1873.21 921863.98 1011861.59 1031861.85 107 1862.72 107.2 1863.81 109 1864.02 115 1867.53 123 1868.3 128 1868.3 134 1869.5 144 1874.5 145 1877 #Mann= 2 ,-1 , 0 91 .03 0 109 .025 0 Bank Sta=92,109 Exp/Cntr=0. 1,0. 1 Type F-M Length L Ch R = l 92.30 ,10,10,10 BEGIN DESCRIPTION: xs 92+30 us of stair to cafe END DESCRIPTION: #Sta/Elev= 14 70 1880 70.1 1864 93 1863.98 95 1863.21 100 1862.16 104.8 1861.8 106 1864.06 113 1868.08 119 1868.11 125 1868.47 135 1869.06 140 1869.06 149 1873.43 150 1877 #Mann= 3 ,-1 , 0 70 .07 0 93 .03 0 113 .025 0 #XS Lid=6 70 1873.2 1871 91.5 1873.2 1871 91.6 1873.2 1871 97.9 1873.2 1871.5 106.7 1873.2 1871.5 113 1869.8 1868.08 Bank Sta=93,106 Exp/Cntr=0.1,0.1 Type RM Length L Ch R. = 1 92.20 ,15,15,15 BEGIN DESCRIPTION: xs 92+20 ds of stair to cafe END DESCRIPTION: #Sta/Elev= 11 70 1880 70.1 1864 93 1863.98 95 1863.21 100 1862.16 104.8 1861.8 106 1864.06 108.9 1864.2 109 1868.08 113 1868.08 113.1 1880 #Mann= 3 ,-1 , 0 APPENDIX E: EXISTING CONDITIONS HEC-RAS INPUT FILE 13 70 .07 0 93 .03 0 108.9 .013 0 #XS Lid=6 70 1873.2 1871 91.5 1873.2 1871 91.6 1873.2 1871 97.9 1873.2 1871.5 106.7 1873.2 1871.5 113 1869.8 1868.08 Bank Sta=93,106 Exp/Cntr-=O.1,0.1 Type RM Length L Ch R = 1 92.05 ,20,29,40 BEGIN DESCRIPTION: off comer of bluebird mall (92+05) END DESCRIP'T'ION: #Sta/Elev= 9 95 1880 95.1 1862.67 961862.55 1001862.27 105.1 1863.03 109.5 1863.34 109.6 1863.4 117 1863.4 117.1 1880 #Mann= 1 ,-1 , 0 95 .03 0 Bank Sta=95.1,117 Exp/Cntr=0.1,0.1 Type RM Length L Ch R = 1 91.76 ,8,8,8 BEGIN DESCRIPTION: xs u/s of bluebird footbridge (91+76) END DESCRIPTION: #Sta/Elev= 12 81 1880 81.1 1863.83 94.1 1862.51 97.5 1861.18 102.4 1861.11 104 1862.7 108.2 1863.8 124 1868.67 128.5 1870.58 164 1870.03 190 1872.6 210 1875 #Mann= 2,-1 , 0 81 .03 0 108.2 .018 0 Bank Sta=81.1,128.5 Exp/Cntr=O. 1,0. 1 Type RM Length L Ch R = 3,91.72 BEGIN DESCRIPTION: Bluebird Walkway END DESCRIPTION: Bridge Culvert--1,0,-1,-1 Deck Dist Width WeirC Skew NumUp NumDn MinLoCord MaxHiCord MaxSubmerge Is-Ogee 2,4,2.6„4,4,1870.6„0.95,0,0,0„ 50 125 125.1 128 1872.84 1872.96 1872.96 1870.58 1871.84 1871.96 0 0 50 125 125.1 128 1872.31 1872.95 1872.95 1870.53 1871.31 1871.31 0 0 BR Coef=-1 , 0, 0 „ 0 ,,,0.8,-I„ 1, WSpro=,,,, 1 0 0 ,-1 ,-1 , 0, 0, 0, 0, 0 Type RM Length L Ch R = 1 91.68 ,18,18,18 BEGIN DESCRIPTION: xs d/s of bluebird footbridge (91+68) END DESCRIPTION: #Sta/Elev= 12 81 1880 81.1 1863.83 94.1 1862.51 97.5 1861.18 102.4 1861.11 104 1862.7 108.2 1863.8 124 1868.67 128.5 1870.58 164 1870.03 190 1872.6 210 1875 #Mann= 2 ,-1 , 0 81 .03 0 124 .018 0 Bank Sta=81.1,128.5 Exp/Cntr=0.1,0.1 Type RIM Length L Ch R = 1 91.50 ,45,40,35 BEGIN DESCRIPTION: start of bluebird mall, d/s edge of bldg. (91+50) END DESCRIPTION: #Sta/Elev= 16 80.9 1880 811868.67 85.5 1868.67 85.6 1867.77 87.9 1862.53 91.3 1861.95 93.5 1861.38 96.2 1860.76 99.7 1860.9 103.4 1861.41 106.3 1864.05 118.5 1869.05 123.7 1870.9 177 1870 190 1872.6 210 1875 #Mann= 3 ,-1 , 0 80.9 .013 0 85.5 .03 0 118.5 .018 0 Bank Sta=855.118.5 APPENDIX E: EXISTING CONDITIONS HEC-RAS INPUT FILE 14 Exp/Cntr=O. 1,0. 1 Type RM Length L Ch R = 1 91.10 ,40,40,40 BEGIN DESCRIPTION: u/s face of culvert (91+10) END DESCRIPTION: #Sta/Elev= 14 551881.09 89 1876 89.1 1862.09 911859.88 991860.16 107 1861.21 107.1 1876 108 1870.15 120 1873.04 127 1871.03 128 1873.61 160 1870.3 170 1872 190 1875 #Mann= 4 ,-1 , 0 55 .03 0 89 .013 0 107.1 .025 0 120 .013 0 Bank Sta=89,107.1 Exp/Cntr=0.1,0.1 Type RM Length L Ch R = 2,90.90 BEGIN DESCRIPTION: Lilthia Way Culvert END DESCRIPTION: Bridge Culvert--1,0,-1,-1 Deck Dist Width WeirC Skew NumUp NumDn MinLoCord MaxHiCord MaxSubmerge Is-Ogee 2,37,2.6„3,3,1873„0.95,0,0,0„ 55 86 107.1 1881.08 1877.23 1877.61 0 0 0 55 86 106.1 1881.08 1877.23 1877.61 0 0 0 BR Coef=-1 , 1 , 0,1, 0 ,,,0.8,0,1,0, WSPro=,,,, 1 0 0 ,,,,-1 ,-1 ,-1 , 0 0 , 0 , 0 Culvert=6,9„38,0.02,0.5,1,41,1,1859.88,98,1860.75,97,Culvert#1 ,0,1 Type RM Length L Ch R = 1 90.70 ,50,35,25 BEGIN DESCRIPTION: d/s face of culvert (90+70) END DESCRIPTION: #Sta/Elev= 11 55 1881 88 1877 88.1 1862.19 92.5 1861.74 1011860.75 1061860.86 106.1 1877.45 120 1870 190 1870 260 1872.5 265 1875 #Mann= 4 ,-1 , 0 55 .03 0 88 .013 0 106.1 .025 0 120 .013 0 Bank Sta=88,106.1 Exp/Cntr=0. 1,0. 1 Type RM Length L Ch R = 1 90.35 ,25,25,25 BEGIN DESCRIPTION: u/s section of paved drive (90+35) END DESCRIPTION: #Sta/Elev= 14 67 1880 67.1 1869.38 76 1874.67 76.1 1869.29 84 1869 29 90.8 1870.82 90.9 1859.85 1001857.52 107.5 1857.92 107.6 1870.97 1191870.15 1741870.32 1901870.03 260 1872.5 #Mann= 3 ,-1 , 0 67 .03 0 90.8 .013 0 107.6 .02 0 #XS Lid=2 90.8 1870.82 1869.62 107.6 1870.97 1869.7 Bank Sta=90.8,107.6 Exp/Cntr-0.1,0.1 Type RM Length L Ch R = 1 90.10 ,70,65,65 BEGIN DESCRIPTION: ds section of paved drive w/dam (90+10) END DESCRIPTION: #Sta/Elev= 10 0 1872.5 321869.06 91.7 1869.87 91.8 1860.44 921859.27 100 1859.32 107 1860.23 107.1 1870.08 147 1871.07 290 1872.5 #Mann= 4 ,-1 , 0 0 .03 0 91.7 .02 0 107.1 .02 0 147 .025 0 #XS Lid=2 APPENDIX E: EXISTING CONDITIONS HEC-RAS INPUT FILE 15 91.7 1869.87 1868.67 107.7 1870.08 1868.88 Bank Sta--91.7,107.1 Exp/Cntr=0.1,0.1 Type RM Length L Ch R = 1 89.45 ,55,65,70 BEGIN DESCRIPTION: xs 89+45 END DESCRIPTION: #Sta/Elev= 11 7.7 1869.32 611863.59 88.4 1860.96 94.2 1856.55 991855.64 105.7 1855.5 108.9 1856.89 120.1 1865.78 156.8 1865.82 185.8 1865.63 194 1866.53 #Mann= 3 ,-1 , 0 7.7 .03 0 88.4 .03 0 120.1 .02 0 Bank Sta=88.4,120.1 Exp/Cntr=O.1,0.1 Type RM Length L Ch R = 1 88.80 ,40,40,40 BEGIN DESCRIPTION: xs 88+80 END DESCRIPTION: #Sta/Elev= 15 23.4 1868.31 38.8 1863.94 50.2 1863.5 84.2 1860.8 93.7 1854.85 96.1 1853.74 103.5 1854.03 105.5 1857.67 115 1859.15 123.2 1864.11 135.5 1864.22 140.3 1864.67 146 1864.43 162.2 1864.98 180 1866 #Mann= 3 ,-1 , 0 23.4 .03 0 84.2 .03 0 123.2 .02 0 Bank Sta=84.2,123.2 Exp/Cntr=0.1,0.1 Type RM Length L Ch R = 1 88.4 ,85,80,30 BEGIN DESCRIPTION: xs 88+40 END DESCRIPTION: #Sta/Elev= 15 01865.43 44.2 1863.47 801860.22 921855.11 94.1 1853.92 100 1853.73 104.8 1854.5 107.9 1855.8 120 1862.28 128.1 1863.33 141.2 1863.18 152 1862.87 155 1863.06 170 1865 190 1867.5 #Mann= 3 ,-1 , 0 0 .03 0 80 .03 0 120 .02 0 Bank Sta=80,120 Exp/Cntr=0. 1,0. 1 Type RM Length L Ch R = 1 87.60 ,35,35,50 BEGIN DESCRIPTION: us of water street (channel skewed 45 degrees) (87+60) END DESCRIPTION: #Sta/Elev= 18 30 1867 30.1 1864.33 50 1861 69.038 1860.6 69.745 1853.83 72.57301 1852.07 75.0475 1852.02 77.522 1851.15 85.299 1851.99 89.1875 1851.97 94.49001 1852.32 105.802 1852.53 112.165 1852.97 114.286 1853.29 122.063 1862.16 160 1862.5 175 1865 185 1867.5 #Mann= 3 ,-1 , 0 30 .025 0 69.038 .03 0 122.063 .015 0 #XS Ineff= 2, 0 0 73.47 1861 91.7 0 1862.1 Bank Sta=69.038,122.063 Exp/Cntr--O. 1,0. 1 Type RM Length L Ch R = 2,87.5 BEGIN DESCRIPTION: Water Street Culvert END DESCRIPTION: Bridge Culvert--1,0,-1,-1 Deck Dist Width WeirC Skew NumUp NUmDn MinLoCord MaxHiCord MaxSubmerge Is-Ogee 2,31,3.1 „4,2,1861 „0.95,0,0,0„ 68 94.5 119.9 122 1860.6 1861.1 1862.16 1862.16 0 0 0 0 60 87 1860.8 1861.1 0 0 BR Coef= 1 , 1 , 0 ,1, 0 ,,,0.8,-1,1,0, APPENDIX E: EXISTING CONDITIONS HEC-RAS INPUT FILE 16 WSPro=,,,, 1 0 0,..,-l ,-1 ,-1 , 0, 0, 0, 0, 0 Multiple Barrel Culy=4,6,5.7,31,0.02,0.5,1,29,1,1850.15,1849.5, 2,Culvert#1 , 0,2 77.5 69 88.8 80.3 Type RM Length L Ch R = 1 87.25 ,35,50,50 BEGIN DESCRIPTION: ds of water street (channel skewed 45 degrees) (87.25) END DESCRIP'T'ION: #Sta/Elev= 13 10 1866 10.1 1864.33 59.662 1860.8 61.783 1857.79 66.025 1851.28 68.146 1849.2 72.7415 1851.43 76.63 1851.79 81.2255 1851.34 83.7 1852.03 87.5885 1861.1 120 1862 180 1865 #Mann= 2 ,-1 , 0 10 .03 087.5885 .02 0 #XS Ineff= 2, 0 0 66 1859 83.7 0 1860 Bank Sta=59.662,87.5885 Exp/Cntr-0.1,0.1 Type RM Length L Ch R = 1 86.75 ,70,90,105 BEGIN DESCRIPTION: us comer of waterfront inn (86+75) END DESCRIP'T'ION: #Sta/Elev= 10 89 1880 89.1 1856.17 90.5 1851.66 921851.35 1001849.24 103.1 1849.78 107 1851.22 112.5 1853.14 126.5 1856.11 145 1860 #Mann= 3 ,-1 , 0 89 .013 0 89.1 .03 0 112.5 .045 0 #XS Ineff= 2, 0 0 89.1 1856.17 112.5 01853.14 Bank Sta=89.1,112.5 Exp/Cntr=0.1,0.1 Type RM Length L Ch R = 1 85.85 ,80,80,80 BEGIN DESCRIPTION: area behind waterfront inn (85+85) END DESCRIPTION: #Sta/Elev= 17 85 1854.7 85.1 1849.04 87.8 1848.02 91 1847.4 93.1 1845.52 93.7 1844.82 96.2 1844.57 98.8 1844.61 100.9 1844.03 103.8 1845.63 107.1 1846.02 110.7 1846.63 114.2 1846.36 115.9 1846.39 118.9 1846.7 119.5 1848.51 129.5 1858.51 #Mann= 3 ,-1 , 0 85 .045 0 87.8 .03 0 119.5 .03 0 Bank Sta=91,119.5 Exp/Cntr=0.1,0.1 Type RM Length L Ch R = 1 85.05 ,90,90,90 BEGIN DESCRIPTION: xs 85+05 END DESCRIPTION: #Sta/Elev= 13 -5 1853.72 65 1854.26 21.2 1854.07 80.3 1850.41 86.7 1846.5 901845.66 951844.66 1001843.87 101.8 1844.55 1071845.71 114.6 1846.49 124 1848.16 130 1853.37 #Mann= 4 ,-1 , 0 -5 .013 0 21.2 .045 0 86.7 .03 0 114.6 .03 0 Bank Sta=86.7,124 Exp/Cntr=0.1,0.1 Type RM Length L Ch R = 1 84.15 ,60,60,60 BEGIN DESCRIPTION: xs 84+15 ds of waterfront inn END DESCRIPTION: #Sta/Elev= 12 221851.97 551850.57 74.5 1848.42 80.6 1847.02 89.4 1846.58 95 1843.27 100 1842.52 102.5 1843.69 107 1846.68 116 1845.07 123 1844.96 145 1851.34 #Mann= 4 ,-1 , 0 22 .013 0 55 .045 0 74.5 .03 0 107 .045 0 Bank Sta=89.4.107 APPENDIX E: EXISTING CONDITIONS HEC-RAS INPUT FILE 17 Exp/Cntr=O. 1,0. 1 Type RM Length L Ch R = 1 83.55 ,110,100,80 BEGIN DESCRIPTION: xs 83+55 along water street END DESCRIPTION: #Sta/Elev= 12 -20 1852.5 20 1852.5 60 1850 68.5 1847.95 84.5 1845.65 931841.85 95.4 1841.48 1061840.48 1071842.14 1201846.78 165 1846.89 180 1860 #Mann= 4 ,-1 , 0 -20 .013 0 20 .045 0 84.5 .03 0 120 .045 0 Bank Sta=84.5,120 Exp/Cntr=O. 1,0. 1 Type RM Length L Ch R = 1 82.55 ,55,60,70 BEGIN DESCRIPTION: xs 82+55 us of dragons teeth END DESCRIPTION: #Sta/Elev= 14 -20 1850.5 20 1850.5 50 1850 841846.01 92.3 1839.7 95 1838.57 101.6 1838.31 107 1839.07 108 1839.59 110 1841.34 125 1843.07 140 1844.76 160 1855 180 1860 #Mann= 4 ,-1 , 0 -20 .013 0 20 .045 0 92.3 .03 0 110 .045 0 Bank Sta=84,110 Exp/Cntr=0. 1,0. 1 Type RM Length L Ch R = 1 81.95 ,45,45,45 BEGIN DESCRIPTION: us of dragons teeth (81+95) END DESCRIPTION: #Sta/Elev= 17 -50 1848.5 -30 1848.5 10 1848.5 84.4 1844.38 881837.88 94.5 1837.02 102 1837.35 103.5 1837.66 110 1837.62 112.5 1837.68 118 1837.53 131 1842.33 148.5 1843.77 155 1846.39 160 1850 170 1852 180 1855 #Mann= 5 ,-1 , 0 -50 .03 0 -30 .013 0 10 .045 0 84.4 .03 0 131 .025 0 Bank Sta=84.4,131 Exp/Cntr=O. 1,0. 1 Type RM Length L Ch R = 5,81.90 BEGIN DESCRIl'IION: dragons teeth END DESCRIPTION: #Inline Weir SE= 20 86.1 0 86.2 1842.76 88.7 1842.76 88.8 0 93.9 0 941841.65 96.5 1841.65 96.6 0 101.9 0 1021841.78 104.5 1841.78 104.6 0 109.9 0 1101841.79 11251841.79 112.6 0 117.9 0 118 1842.29 131 1842.33 150 1842.33 IW Dist,WD,Coef,Skew,MaxSub,Min_EI,Is_Ogee,SpillHt DesHd 1,2.5,3„0.95„ 0 ,,,0,0, Type R.M Length L Ch R = 1 81.50 ,40,40,40 BEGIN DESCRIPTION: xs 81+50 us of van ness road END DESCRIPTION: #Sta/Elev= 12 -200 1850 51845.67 591846.46 89.5 1836.19 921835.72 100.8 1835.52 109 1835.78 109.1 1836.36 117 1845.88 141 1847.01 145 1851.36 177 1852.12 #Mann= 1 ,-1 .0 -200 .03 0 #XS Ineff= 2, 0 0 89.5 1847 109.1 0 1847.5 Bank Sta=59,117 Exp/Cntr=0.1,0.1 Type RM Length L Ch R = 2 ,81.40 APPENDIX E: EXISTING CONDITIONS HEC-RAS INPUT FILE 18 BEGIN DESCRIPTION: Van Ness Culvert END DESCRIPTION: Bridge Culvert--1,0,-1,-1 Deck Dist Width WeirC Skew NumUp NumDn MinLoCord MaxHiCord MaxSubmerge Is-Ogee 2,36,2.6.,4,4,1845.67„0.95,0,0,0„ 5 89.5 117 177 1845.67 1847.1 1847.69 1852.12 0 0 0 0 -10 90 112 157 1844.18 1847.1 1847.64 1848.85 0 0 0 0 BR Coef=-1 , 1 , 0,1, 0 ,,,0.8,0,1,0, WSPro=.,,, 1 0 0,,,,-l ,-1 ,-1 , 0, 0, 0, 0, 0 Culvert=5,7.54,20,36,0.02,0.5,1,41,1,1835.65,100,1835.4,100,Culvert #1 , 0,2 Type RM Length L Ch R. = 1 81.10 ,20,20,20 BEGIN DESCRIPTION: xs 81+10 ds of van ness END DESCRIPTION: #Sta/Elev= 10 -200 1850 -101844.18 431845.58 82.5 1845.4 901835.39 100 1835.4 110 1835.37 115 1846.78 157 1848.85 197 1851.83 #Mwm= 1 ,-1 , 0 -200 .03 0 #XS Ineff= 2, 0 0 90 1845 110 0 1846 Bank Sta=82.5,115 Exp/Cntr=0. 1,0. 1 Type RM Length L Ch R. = 1 80.90 ,40,40,40 BEGIN DESCRIPTION: xs 80+90 us of rr bridge END DESCRIPTION: #Sta/Elev= 12 -200 1850 -101844.18 431845.58 82.5 1845.4 901834.85 96 1834.19 102 1834.04 109 1834.12 1301840.564 157 1848.85 197 1851.83 198 1860 #Mann= 2,-1 , 0 -200 .03 0 -10 .03 0 #XS Ineff= 2, 0 0 91 1857 109 0 1858 Bank Sta=82.5,130 Exp/Cntr=O. 1,0. 1 Type PM Length L Ch R = 3,80.7 BEGIN DESCRIPTION: Railroad Bridge END DESCRIPTION: Bridge Culvert--1,Q-1,-1 Deck Dist Width WeitC Skew NumUp NUmDn MinLoCord MaxHiCord MaxSubmerge Is-Ogee 2,37.2.6.,8.8.1857.24„0.95,0,0,0„ -200 0 90 91 100 109 110 200 1857 1857.24 1858.16 1858.16 1858.16 1858.16 1858.16 1859.19 0 0 0 1845.47 1849.92 1843.12 0 0 0 92 93 102 108 ill 113 200 1857.24 1858.16 1858.16 1858.16 1858.16 1858.16 1858.16 1859.19 0 0 1844.6 1849.05 1847.64 1834.77 0 0 BR Coef=-l , 1 , 0,1, 0 ,,,0.8,0,1,0, WSPro=,,,, 1 0 0 ,-1 ,-1 .0 , 0, 0, 0, 0 Type RM Length L Ch R = 1 80.5 ,35,35,35 BEGIN DESCRIPTION: xs 80+50 ds of rr bridge END DESCRIPTION: #Sta/Elev= 10 371856.63 501851.376 751841.271 92 1834.4 1001833.81 108 1834.23 111 1834.77 130 1841 194 1857.64 196 1860 #Mann= I .-1 , 0 37 .03 0 #XS Ineff= 2, 0 0 92 1855 111 0 1855 Bank Sta=75.130 APPENDIX E: EXISTING CONDITIONS HEC-RAS INPUT FILE 19 Exp/Cntr=0.1,0.1 Type RM Length L Ch R = 1 80. 15 ,1,1,1 BEGIN DESCRIPTION: xs 80+15 concrete dam END DESCRIPTION: #Sta/Elev= 9 781841.76 921833.87 104.5 1833.44 1071833.88 1121837.72 122.5 1840.32 153.5 1842.01 1851840.26 300 1842.5 #Mann= 3 ,-1 , 0 78 .03 0 112 .025 0 122.5 .013 0 Bank Sta=78,112 Exp/Cntr=0. 1,0. 1 Type RM Length L Ch R = 1 80.14 ,110,109,110 BEGIN DESCRIPTION: xs 80+14 ds of concrete dam END DESCRIPTION: #Sta/Elev= 9 781841.76 921833.87 97.5 1830.43 1071833.88 1121837.72 122.5 1840.32 153.5 1842.01 1851840.26 300 1842.5 #Mann= 3 ,-1 , 0 78 .03 0 112 .025 0 153.5 .013 0 Bank Sta=78,112 Exp/Cntr=0. 1,0. 1 Type RM Length L Ch R = 1 79.05 ,65,65,65 BEGIN DESCRIPTION: xs 79+05 END DESCRIPTION: #Sta/Elev= 9 73.6 1836.84 90.2 1830.42 96 1829.36 101 1829.16 108 1829.9 115.5 1834.57 127 1834.1 183 1834.41 330 1837.5 #Mann= 3 ,-1 , 0 73.6 .03 0 115.5 .025 0 127 .013 0 #XS Ineff= 2, 0 0 73.6 1836.84 115.5 01834.57 Bank Sta=73.6,115.5 Exp/Cntr=0. 1,0. 1 Type RM Length L Ch R = 1 78.40 ,80,90,95 BEGIN DESCRIPTION: xs 78+40 (high water mark available) END DESCRIPTION: #Sta/Elev= 12 621834.99 831835.65 951828.48 971827.41 99.5 1827.21 104 1827.7 6 108 1828.2 116 1832.73 153.5 1832.61 211 1833.38 330 1835 370 1837.5 #Mann= 4,-1 , 0 62 .03 0 95 .03 0 116 .025 0 153.5 .013 0 #XS Ineff= 2.0 0 831835.65 116 01832.73 Bank Sta=83,116 Exp/Cntr=0. 1.0. 1 Type RM Length L Ch R = 1 77.5 ,75,75,90 BEGIN DESCRIPTION: xs 77+50 END DESCRIPTION: #Sta/Elev= 14 67.5 1833.76 791834.14 921826.57 961825.14 101.5 1825.17 105 1825.69 107 1826.56 115 1830.79 135 1829.98 163 1830.39 1831831.13 210 1832.5 400 1835 450 1837.5 #Mann= 3 >-1 , 0 67.5 .03 0 115 .025 0 135 .013 0 #XS Ineff= 2, 0 0 791834.14 115 01830.79 Bank Sta=79.115 Exp/Cntr=0.1,0.1 Type RM Length L Ch R = 1 76.75 ,70,75,80 BEGIN DESCRIPTION: APPENDIX E: EXISTING CONDITIONS HEC-RAS INPUT FILE 20 xs 76+75 (high water mark available) END DESCRIPTION: #Sta/Elev= 12 66.5 1831.66 791831.73 91 1824.7 951823.25 1001823.56 103.2 1823.6 110 1824.46 121.5 1829.23 135 1833.19 179 1828.8 199 1832 2051831.88 #Mann= 3 ,-1 , 0 66.5 .03 0 121.5 .025 0 135 .013 0 Bank Sta=79,121.5 Exp/Cntr-0.1,0.1 Type RM Length L Ch R = 1 76.00 ,50,45,25 BEGIN DESCRIPTION: xs 76+00 END DESCRIPTION: #Sta/Elev= 14 0 1832 40 1832 76.5 1829.73 86.5 1827.21 92 1823.1 94 1821.58 101 1821.81 102 1823.15 106.5 1823.25 111 1822.98 137 1829.39 147 1825.68 190 1826.71 231 1837.74 #Mann= 4,-1 , 0 0 .013 0 40 .03 0 111 .025 0 147 .013 0 Bank Sta=86.5,111 Exp/Cntr=0.1,0.1 Type RM Length L Ch R = 1 75.55 ,65,65,65 BEGIN DESCRIPTION: xs 75+55 us of hersey st bridge END DESCRIPTION: #Sta/Elev= 17 -50 1832.5 0 1830 40 1829.5 471828.31 951821.68 95.1 1820.1 97 1819.29 100 1819.08 103.5 1819.17 106 1819.93 111 1822.64 127 1827.74 143 1827.79 157 1827.87 184 1828.19 2081828.62 250 1832 #Mann= 5 ,-1 , 0 -50 .03 0 0 .013 0 47 .03 0 111 .025 0 157 .013 0 #XS Ineff= 2, 0 0 951828.31 111 01827.74 Bank Sta=95,111 Exp/Cntr=0.1,0.1 Type RM Length L Ch R = 3 75.25 BEGIN DESCRIPTION: Hershey Street Bridge END DESCRIPTION: Bridge Culvert--1,0,-1,-1 Deck Dist Width WeirC Skew NumUp NllmDn MinLoCord MaxHiCord MaxSubmerge Is-Ogee 5,55?.6.,10,11,1827.74„0.95,0,0.0„ 47 75 92 95.1 97 102 104 106 109 126 1828.31 1828.7 1829.87 1829.87 1829.87 1829.9 1829.9 1830 1830 1827.74 0 0 0 1820.1 1824.82 1825.77 1825.56 1822.86 0 0 33 61 81 89 93 95 100 102 104 107 118 1827.28 1828.25 1828.43 1828.93 1828.75 1828.75 1828.75 1828.75 1828.75 1828.75 1828.23 0 0 0 0 1820 1824.7 1825.67 1825.45 1822.75 0 0 BR Coef= I , 1 , 0,1, 0 ,,,0.8,0,1,0, WSPro=,,,, 1 0 0 1-1 1-1 , 0 , 0, 0, 0, 0 Type RM Length L Ch R = 1 74.9 90,110,130 BEGIN DESCRIPTION: xs 74+90 ds of hersey street bridge END DESCRIPTION: #Sta/Elev= 14 0 1830 341827.58 561827.86 811826.89 891818.88 92.5 1816.12 102 1816.71 104 1817.84 107.5 1818.73 117 1828-23 1201826.19 182 1826.1 2231826.78 250 1828 #Mann= 1 ,-1 , 0 0 .03 0 #XS Ineff= 2, 0 0 811826.89 120 01826.19 APPENDIX E: EXISTING CONDITIONS HEC-RAS INPUT FILE 21 Bank Sta=81,117 Exp/Cntr=O. 1,0. 1 Type RM Length L Ch R = 1 73.80 ,0,0,0 BEGIN DESCRIPTION: xs 73+80 last xs END DESCRIPTION: #Sta/Elev= 13 431827.22 531824.77 701818.08 891816.28 901815.36 941815.46 991815.96 1061816.11 109 1816.6 1161820.42 1401820.61 173 1821.3 300 1821.3 #Mann= 1 -I , 0 43 .03 0 Bank Sta=70,116 Exp/Cntr=O. 1,0. 1 Chan Stop Cuts=-1 APPENDIX E: PROPOSED CONDITIONS HEC-RAS INPUT FILE 1 Geom Title=Proposed Conditions, 100 w/ Hersey St Viewing Rectangle= 9.23127235272031E-02 , 0.72552564157034 , 0.8763 84605 1 40046 , 0.243 17 1 687096909 River Reach=Ashland Cr rl Junct Up Dn= Reach XY= 2 .111731 .8652882 .705679 .2641931 Rch Text X Y=0.4124629,0.7205357 Reverse River Text= 0 Type RM Length L Ch R = 1 ,115.90 ,65,70,75 BEGIN DESCRIPTION: 115+90 END DESCRIPTION: #Sta/Elev= 12 33.7 1943.35 57.5 1940.8 841938.12 90.7 1934.65 93 1933.7 99 1933.35 103 1932.95 108 1933.48 110.5 1934.8 122 1938.68 129.5 1938.82 144 1944.1 #Mann= 3 ,-1 , 0 33.7 .045 0 90.7 .03 0 110.5 .045 0 Bank Sta=84,122 Exp/Cntr--O. 1,0. 1 Type RM Length L Ch R = I ,115.20 ,10,10,10 BEGIN DESCRIPTION: 115+20 END DESCRIPTION: #Sta/Elev= 14 201943.71 361938.99 711939.47 88.5 1933.35 901931.03 93 1930.41 97 1930.31 99.5 1931.32 104 1932.28 106 1932.87 111 1938.82 113.2 1939.25 135 1940.67 140 1945 #Mann= 4 ,-1 , 0 20 .025 0 71 .045 0 88.5 .03 0 106 .045 0 Bank Sta=71,113.2 Exp/Cntr=O. 1,0. 1 Type RM Length L Ch R = 3,115.15 BEGIN DESCRIPTION: Footbridge END DESCRIPTION: Bridge Culvert--1,0,0,-I Deck Dist Width WeirC Skew NumUp NumDn MinLoCord MaxHiCord MaxSubmerge Is-Ogee 2,6,2.6„4,4,1939„0.95,0,0,0„ 65 70 117 122 1939 1940.38 1940.83 1939 1939 1939.22 1939.22 1939 65 70 117 122 1939 1940.38 1940.83 1939 1939 1939.22 1939.22 1939 BR Coef= 1 , 0, 0- 0 ,,,0.8,-1„1, WSPro=,,,, 1 0 0 ,,,,-1 ,-1 ,-1 , 0, 0, 0, 0, 0 Type RM Length L Ch R = I ,115.10 ,40,35,30 BEGIN DESCRIPTION: 115+10 END DESCRIPTION: #Sta/Elev= 14 201943.71 361938.99 711939.47 88.5 1933.35 901931.03 93 1930.41 97 1930.31 99.5 1931.32 104 1932.28 106 1932.87 111 1938.82 113.2 1939.25 135 1940.67 140 1945 #Mann= 4,-1 , 0 20 .025 0 71 .045 0 88.5 .03 0 106 .045 0 Bank Sta=71,113? Exp/Cntr=0.1,0.1 Type RM Length L Ch R = I ,114.75 ,100,95,90 BEGIN DESCRIPTION: 114+75 END DESCRIPTION: #Sta/Elev= 15 6 1943 111938.17 321936.38 54.2 1936.64 87.8 1937.02 APPENDIX E: PROPOSED CONDITIONS HEC-RAS INPUT F LE 2 94.5 1931.88 951929.95 991929.62 107.2 1930.13 1081931.85 112.2 1930.98 119 1933.47 123.3 1938.22 132 1938.43 143.2 1939.46 #Mann= 4,1 , 0 6 .025 0 87.8 .045 0 94.5 .03 0 119 .045 0 Bank Sta=87.8,123.3 Exp/Cntr=0.1,0.1 Type RM Length L Ch R = 1 ,113.80 ,80,74,72 BEGIN DESCRIPTION: 113+80 END DESCRIPTION: #Sta/Elev= 15 -81936.42 101936.42 531934.62 56.2 1934.71 661934.61 70.5 1934.02 86.8 1932.13 881929.87 90.4 1929.11 941928.27 99.5 1927.52 106.8 1928.56 108 1930.02 121 1937.85 130.7 1937.92 #Mann= 4 ,-1 , 0 -8 .025 0 66 .045 0 88 .03 0 108 .045 0 #Block Obstruct= 1 ,-1 10 53 1937 Bank Sta=86.8,121 Exp/Cntr=0.1,0.1 Type RM Length L Ch R = i ,113.06 ,81,81,81 BEGIN DESCRIPTION: 113+06 END DESCRIPTION: #Sta/Elev= 17 -701936.47 -40 1932.9 401932.35 661932.48 84.1 1933.9 84.2 1931.55 90.5 1926.61 94.3 1926.54 97.4 1926.06 102.5 1926.76 107.3 1926.45 111 1927.51 115 1927.52 122 1933.9 123.2 1933.87 135 1935.51 147 1944.94 #Mann= 4,-1 , 0 -70 .025 0 84.2 .045 0 90.5 .03 0 123.2 .045 0 Bank Sta=84.1,122 Exp/Cntr=0.1,0.1 Type RM Length L Ch R = 1 ,112.25 ,50,50,45 BEGIN DESCRIPTION: 112+25 END DESCRIPTION: #Sta/Elev= 16 -1051936.99 -951934.52 -601931.82 -151931.08 58.5 1929.59 88.4 1928.32 90 1924.1 90.8 1923.17 97.4 1922.72 99.5 1921.89 106.8 1921.37 108.5 1921.66 109.2 1924.34 119 1931.17 136.5 1931.75 143.7 1935.86 #Mann= 3 ,-1 , 0 -105 .025 0 90 .03 0 109.2 .045 0 Bank Sta=88.4,119 Exp/Cntr=0.1,0.1 Type RM Length L Ch R = 1 ,111.75* ,50,50,45 #Sta/Elev= 28 -108.99 1935.91 -98.73 1934.36 -62.81 1931.91 -37.8 1930.94 -16.64 1930.62 -16.351930.62 58.77 1928.17 59.71 1928.13 73.85 1928.67 89.45 1927.19 90.45 1924.81 90.95 1924.21 95.07 1922.89 96.39 1922.12 100.95 1920.65 104.1 1920.83 104.31 1921.04 105.4 1922.43 106.5 1922.9 108.55 1923.78 113.07 1925.04 118 1925.87 123.55 1928.61 141.3 1929.69 147.68 1929.85 151.04 1930 162.35 1932.45 165 1935 #Mann= 3 ,-1 , 0 -108.99 .025 0 89.45 .03 0 123.55 .045 0 Bank Sta=89.45,123.55 Exp/Cntr=0. 1,0. 1 Type RM Length L Ch R = 1 ,111.25 ,15,15,15 BEGIN DESCRIPTION: 111+25 END DESCRIPTION: #Sta/Elev= 17 -1131934.82 -401930.47 -181930.16 60 1926.7 74.5 1928.38 90.5 1926.05 95.1 1919.93 100 1920 103.2 1921.04 106.2 1922.03 APPENDIX E: PROPOSED CONDITIONS HEC-RAS INPUT FILE 3 112.8 1922.86 120 1922.65 128.1 1926.06 152.3 1927.83 161 1928.03 181 1929.03 187 1935 #Mann= 6 ,-1 , 0 -113 .025 0 130 .013 0 60 .025 0 74.5 .045 0 95.1 .03 0 120 .045 0 Bank Sta--90.5,128.1 Exp/Cntr=0.1,0.1 Type RM Length L Ch R = 3,111.18 BEGIN DESCRIPTION: Maintenance Bridge END DESCRIPTION: Bridge Culvert--1,0,0,-1 Deck Dist Width WeirC Skew NumUp NutnDn MinLoCord MaxHiCord MaxSubmerge Is_Ogee 1,12,2.6„2,2,1926.7„0.95,0,0,0„ 77 160 1930 1930 1928 1928 77 160 1930 1930 1928 1928 BR Coef= I , 0, 0, 0 ,,,0.8,-1„1, WSPro=,,,, I 0 0 ,-1 ,-1 , 0, 0, 0, 0, 0 Type RM Length L Ch R = 1 ,111.10 ,40,27,15 BEGIN DESCRIPTION: 111+10 END DESCRIPTION: #Sta/Elev= 15 -1181934.02 -281929.47 -101929.34 581926.44 931925.66 95.6 1920.77 100.8 1919.18 104.8 1919.63 113.2 1921.86 122 1923.22 130.6 1926.77 144.2 1927.83 161 1928 181 1929 186 1935 #Mann= 6 ,-1 , 0 -118 .025 0 -28 .013 0 58 .025 0 93 .045 0 95.6 .03 0 122 .045 0 Bank Sta=93,130.6 Exp/Cntr-0.1,0.1 Type RM Length L Ch R = 1 ,110.83 ,50,73,80 BEGIN DESCRIPTION: 110+83 END DESCRIPTION: #Sta/Elev= 12 -20 1928 -101926.26 60 1924 901920.46 96.5 1920.46 100.4 1920.41 105 1920.39 112.7 1920.57 116.4 1921.72 122 1925.46 156.5 1926.03 166 1928 #Mann= 3 ,-1 , 0 -20 .013 0 60 .025 0 116.4 .045 0 Bank Sta=60,122 Exp/Cntr=0.1,0.1 Type RM Length L Ch R = 1 ,110.09 ,20,15,5 BEGIN DESCRIPTION: 110+09 END DESCRIPTION: #Sta/Elev= 11 -90 1926.7 0 1924.5 60 1923 75 1922 89.6 1921.02 95 1916.29 108 1915.85 115.2 1915.83 115.3 1921.1 119.5 1921.75 155 1926.81 #Mann= 4,-1 , 0 -90 .025 0 0 .013 0 60 .025 0 115.3 .045 0 Bank Sta=75,119.5 Exp/Cntr=0.1,0.1 Type RM Length L Ch R = 1 ,109.95 ,50,50,45 BEGIN DESCRIPTION: 109+95 END DESCRIPTION: #Sta/Elev= 14 -90 1924.8 5 1923.75 67 1922 88.2 1921.91 89.4 1919.22 94.5 1918.15 100.2 1917.43 105 1917.23 108.2 1916.77 109.5 1916.78 116 1917.49 122.4 1922.28 146.8 1923.9 153.1 1926.81 APPENDIX E: PROPOSED CONDITIONS HEC-RAS INPUT FILE 4 #Mann= 4,-l , 0 -90 .025 0 5 .013 0 67 .03 0 116 .045 0 Bank Sta=88.2,122.4 Exp/Cntr=O.1,0.1 Type RM Length L Ch R = 1 ,109.44 ,20,20,15 BEGIN DESCRIPTION: 109+44 END DESCRIPTION: #Sta/Elev= 9 -95 1923.5 14.5 1921.2 65 1921.5 841912.08 101.4 1911.87 108.7 1912.89 121 1920.9 137 1920.54 147 1925 #Mann= 4 ,-1 , 0 -95 .025 0 14.5 .013 0 65 .03 0 121 .045 0 Bank Sta=65,121 Exp/Cntr---O.1,0.1 Type RM Length L Ch R = 1 ,109.25 ,75,75,75 BEGIN DESCRIP'T'ION: 109+25 END DESCRIPTION: #Sta/Elev= 12 -85 1923 251920.19 67.8 1921-03 82.6 1914.2 85.1 1913.07 93.4 1912.07 109.1 1911.15 111.2 1912.9 111.5 1914.54 120 1920.9 135 1920.54 137 1921.89 #Mann= 5 ,-1 , 0 -85 .025 0 25 .013 0 67.8 .025 0 82.6 .03 0 120 .045 0 Bank Sta=67.8,120 Exp/Cntr=0.1,0.1 Type RM Length L Ch R = 1 ,108.50 ,65,65,70 BEGIN DESCRIPTION: 108+50 END DESCRIPTION: #Sta/Elev=14 -501923.27 -351918.55 251917.98 451918.64 71.6 1918.46 80.5 1917.99 90.1 1910.16 91.8 1907.99 94.8 1907.11 1001908.27 104.1 1908.79 109.2 1909.9 131.2 1920.01 143.1 1919.86 #Mann= 5 ,-1 , 0 -50 .025 0 25 .013 0 71.6 .03 0 109.2 .045 0 131.2 .025 0 Bank Sta=80.5,131.2 Exp/Cntr-0.1,0.1 Type RM Length L Ch R = 1 ,107.85 ,85,85,85 BEGIN DESCRIPTION: 107+85 END DESCRIPTION: #Sta/Elev= 19 -30 1923 101917.27 201916.49 43.4 1916.51 71.5 1915.99 75.5 1916.05 83.9 1915.34 92.9 1907.92 971906.41 1001906.56 106.8 1905.8 108.5 1907.9 110 1907.95 118.5 1911.82 122.7 1913.08 146 1914.63 147 1917.05 160 1917.19 170 1923 #Mann= 4,-l , 0 -30 .013 0 71.5 .03 0 122.7 .025 0 160 .045 0 Bank Sta=83.9,122.7 Exp/Cntr=O.1,0.1 Type RCS Length L Ch R = 1 ,107.00 ,40,41.67,43.33 BEGIN DESCRIPTION: 107+40 END DESCRIPTION: #Sta/Elev= 18 -50.1 1920 -50 1910 231913.36 491913.37 78.4 t912.65 83.1 1912.67 87.1 1912.18 92.8 1905.09 941904.41 100.4 1903.35 105.2 1903.7 108.3 1905.16 111.5 1905.5 114.8 1905.58 118.7 1911.97 1431911.83 184 1912.5 2111920.25 #Mann= 5 ,-1 , 0 -50.1 .025 0 23 .013 0 83.1 .03 0 APPENDIX E: PROPOSED CONDITIONS HEC-RAS INPUT FILE 5 118.7 .025 0 184 .045 0 Bank Sta=87.1,118.7 Exp/Cntr=0.1,0.1 Type RM Length L Ch R = 1 ,106.583*,40,41.67,43.33 #Sta/Elev= 30 -58.39 1917.6 -58.29 1910.82 -57.45 1909.94 16.97 1912.1 17.05 1912.1 43.78 1912.15 50.06 1912.05 72.88 1911.95 74.1 1911.87 78.94 1911.65 83.07 1911.11 90.17 1904.69 91.66 1903.88 95.62 1902.58 99.63 1902.12 103.68 1902.4 104.85 1902.55 108.22 1903.8 108.25 1903.8 110.75 1904.17 111.7 1904.43 115.29 1905.23 119.53 1910.36 131.91 1910.5 137.11 1910.62 148.27 1910.68 154.15 1910.78 196.74 1911.36 215.67 1914.51 228.67 1918.83 #Mann= 5 ,-1 , 0 -58.39 .021 0 16.97 .013 0 74.1 .03 0 83.07 .025 0 215.67 .045 0 Bank Sta=83.07,119.53 Exp/Cntr=0.1,0.1 Type RM Length L Ch R = 1 ,106.166*,40,41.67,43.33 #Sta/Elev= 30 -66.69 1915.19 -66.58 1911.64 -65.72 1909.85 10.95 1910.85 11.02 1910.85 38.56 1910.92 45.03 1910.89 68.54 1911.23 69.79 1911.1 74.78 1910.62 79.03 1910.05 87.53 1904.29 89.32 1903.35 94.06 1901.28 98.87 1900.88 103.24 1901.19 104.51 1901.4 108.15 1902.44 108.17 1902.45 110.87 1902.94 111.91 1903.37 115.78 1904.87 120.37 1908.75 134.66 1909.08 140.66 1909.35 153.53 1909.53 160.33 1909.66 209.49 1910.22 231.34 1911.92 246.33 1917.41 #Mann= 5 ,-1 , 0 -66.69 .017 0 10.95 .013 0 68.54 .024 0 79.03 .025 0 231.34 .045 0 Bank Sta=79.03,120.37 Exp/Cntr=O. 1,0. 1 Type RM Length L Ch R = 1 ,105.75 ,15,15,15 BEGIN DESCRIPTION: 105+75 END DESCRIPTION: #Sta/Elev= 17 -751912.79 -741909.75 51909.59 401909.72 64.2 1910.5 751908.98 92.5 1899.98 98.1 1899.65 102.8 1899.97 108.1 1901.09 111 1901.71 121.2 1907.14 137.4 1907.67 144.2 1908.09 166.5 1908.53 2471909.33 2641915.99 #Mann= 4,-1 , 0 -75 .013 0 64.2 .03 0 121.2 .025 0 247 .045 0 Bank Sta=75,121.2 Exp/Cntr=0.1,0.1 Type RM Length L Ch R = 2,105.70 BEGIN DESCRIPTION: Memorial Atkinson END DESCRIPTION: Bridge Culvert--1,0,0,-1 Deck Dist Width WeirC Skew NumUp NllmDn MinLoCord MaxHiCord MaxSubmerge Is-Ogee 3,10,2.6„4,4,1908„0.95,0,0,0„ 76 90 110 122 1908.25 1910.15 1910.19 1908.25 0 0 0 0 76 90 110 122 1908.25 1910.15 1910.19 1908.25 0 0 0 0 BR Coef=-1 , 1 , 0,1, 0 ,,,0.8,-1,1,0, WSpm=.,,, 1 0 0 ""-1 ,-1 ,-1 , 0, 0, 0, 0, 0 Culvert=7,7.41,20,10,0.013,0.5,1,41,1,1899.65,100,1900.12,100.Culvert #1 .0.2 Type RM Length L Ch R = 1 ,105.60 ,25,25,25 BEGIN DESCRIPTION: 105+60 END DESCRIPTION: #Sta/Elev= 17 -751912.79 -741909.75 51909.59 401909.72 64.2 1910.5 751908.46 8781904.72 901901.44 931900.68 1001900.12 107.2 1899.78 109.5 1901.75 110.8 1908.37 123.5 1907.1 1668 1908.53 2471909.33 2641915.99 APPENDIX E: PROPOSED CONDITIONS HEC-RAS INPUT FILE 6 #Mann= 4,-1 , 0 -75 .013 0 64.2 .03 0 110.8 .025 0 247 .045 0 Bank Sta=75,110.8 Exp/Cntr=0.1,0.1 Type RM Length L Ch R = 1 ,105.35 ,125,125,125 BEGIN DESCRIPTION: 105+35 END DESCRIPTION: #Sta/Elev= 21 -551912.82 -541909.75 -201909.65 0 1909.1 171907.63 66.8 1907.58 721907.62 81.3 1906.97 91.2 1901.1 941900.38 100 1900.13 105.5 1900.13 112.3 1900.39 114.3 1900.87 118 1904.33 139.9 1904.98 1521906.93 1821907.62 2191908.05 2541908.73 269 1911.88 #Mann= 5 ,-1 , 0 -55 .013 0 72 .03 0 91.2 .015 0 139.9 .025 0 254 .045 0 Bank Sta=81.3,118 Exp/Cntr=O.1,0.1 Type RIM Length L Ch R = 1 ,104.10 ,110,120,130 BEGIN DESCRIPTION: 104+10 END DESCRIPTION: #Sta/Elev= 18 151903.66 381903.94 671903.33 72.2 1903.41 77.9 1903.79 781903.64 84.1 1902.65 901896.89 97.1 1895.69 99.8 1895.66 110 1894.99 115.1 1896.42 123.2 1900.95 165 1902.09 175 1902.35 1761903.55 255 1905.6 265 1915 #Mann= 4,-1 , 0 15 .013 0 78 .03 0 123.2 .025 0 255 .045 0 Bank Sta=84.1,123.2 Exp/Cntr~0.1,0.1 Type RIM Length L Ch R = 1 ,102.90 ,45,45,40 BEGIN DESCRIPTION: 102+90 END DESCRIPTION: #Sta/Elev= 18 251899.95 46.9 1900.23 74.2 1899.64 781899.73 80.3 1899.58 86.8 1893.02 96.5 1892.18 1001891.82 106 1891.3 111.2 1892.85 115.8 1896.4 138.7 1897.65 165 1898.48 180 1898.74 181 1899.94 2151902.73 280 1903.3 290 1913 #Mann= 4 ,-1 , 0 25 .013 0 80.3 .03 0 115.8 .025 0 280 .045 0 Bank Sta=80.3,115.8 Exp/Cntr---O.1,0.1 Type RIM Length L Ch R = 1 ,102.45 ,60,55,50 BEGIN DESCRIPTION: 102+45 END DESCRIPTION: #Sta/Elev= 19 25 1901 261898.35 541898.51 771898.16 84.9 1897.91 87.2 1893.77 90.5 1892.13 95.4 1890.83 1001890.48 109.2 1890.74 115 1890.3 121.4 1895.75 146 1896.66 166 1897.83 186 1897.86 1871899.06 2231901.99 285 1902.8 295 1912 #Mann= 4,1 , 0 25 .013 0 84.9 .03 0 121.4 .025 0 285 .045 0 Bank S ta=84.9,121.4 Exp/Cntr-O.1,0.1 Type RM Length L Ch R = 1 ,101.90 ,55,60,65 BEGIN DESCRIPTION: 101+90 END DESCRIPTION: #StaiElev= 20 29 1901 30 1896.6 51.5 1896.56 68.9 1895.93 79.2 1896.13 APPENDIX E: PROPOSED CONDITIONS HEC-RAS INPUT FILE 7 841895.96 85.5 1894.66 91.1 1890.08 97.3 1888.44 106.1 1888.14 107 1890.32 112.1 1894.29 126.1 1895.25 152 1895.45 185 1896.64 1951896.65 248 1901.6 2631901.81 280 1902 290 1912 #Mann= 4 ,-1 , 0 29 .013 0 85.5 .03 0 107 .025 0 280 .045 0 Levees,,-1,165,1898 Bank Sta=84,112.1 Exp/C=4. 1,0. 1 Type RM Length L Ch R = 1 ,101.30 ,40,45,50 BEGIN DESCRIPTION: 101+30 END DESCRIPTION: #Sta/Elev= 16 20 1896 211894.41 571894.24 731893.84 74.6 1893.79 80.2 1893.98 931887.48 93.2 1887.42 96.7 1886.67 1001886.47 104.6 1886.64 110.8 1887.59 118 1894 1411893.52 2141894.53 237 1897.34 #Mann= 3 ,-1 , 0 20 .013 0 80.2 .03 0 118 .025 0 Levees,,-1,134,1896.5 Bank Sta=80.2,118 Exp/Cntr=0.1,0.1 Type RM Length L Ch R. = 1 ,100.85 ,15,15,15 BEGIN DESCRIPTION: 100+85 END DESCRIPTION: #Sta/Elev= 13 30 1895 311893.53 521893.33 68.1 1892.6 71 1892.5 86.6 1884.71 102.4 1884.71 107.5 1885.77 115 1893 131 1892.13 1581892.93 2481893.97 2971897.11 #Mann= 3 ,-1 , 0 30 .013 0 71 .03 0 115 .025 0 Levees,,-1,131,1895.5 Bank Sta=71,115 Exp/Cntr--0. 1,0. 1 Type RM Length L Ch R. = 1 ,100.70 ,35,35,40 BEGIN DESCRIPTION: 100+70 END DESCRIPTION: #Sta/Elev= 13 301894.59 311893.12 521892.92 68.1 1892.19 711892.09 86.6 1884.3 102.4 1884.3 107.5 1885.36 115 1892.59 131 1891.72 1581892.52 2481893.56 297 1896.7 #Mann= 3 ,-1 , 0 30 .013 0 71 .03 0 115 .025 0 Levee=-1, 77,1895.5,-1.131,1895.5 Bank Sta=71,115 Exp/Cntr=0.1,0.1 Type RM Length L Ch R. = 1 ,100.35 ,25,25,60 BEGIN DESCRIPTION: 100+35 END DESCRIPTION: #Sta/Elev= 19 01893.55 451892.02 601892.82 80.1 1891.03 85.2 1890.11 86.9 1890 871883.36 1001883.36 1191883.36 119.1 1887.5 128 1887.5 128.1 1891 135.6 1891.58 166 1892.37 188 1892.41 2051892.82 2581893.51 2801895.65 2891898.32 #Mann= 3 ,-1 , 0 0 .013 0 80.1 .03 0 135.6 .025 0 Levee=-1,87,1894.5.-1.128.1894.5 Bank Sta=86.9.128.1 Exp/Cntr-0. 1,0. 1 Type RM Length L Ch R = I ,100.10 ,75.75,75 BEGIN DESCRIPTION: xs at us windburn way (100+10), modified for 32' bridge span 25 degree skew (0.91) made in channel section (formerly 86.9 to 120.1) END DESCRIPTION: APPENDIX E: PROPOSED CONDITIONS HEC-RAS INPUT FILE 8 #Sta/Elev= 21 2 1895 31892.95 361891.65 47.5 1891.5 76.5 1888.83 86.9 1883 86.991 1882 98.821 1882 117.021 1882 117.112 1890 128.012 1890.16 135.012 1889.92 173.012 1890.95 200.012 1891.14 232.012 1891.81 283.012 1891.24 298.012 1891.29 318.012 1891.35 338.012 1894 361.012 1896.1 367.012 1901.28 #Mann= 4 ,-1 , 0 2 .013 0 76.5 .018 0 86.9 .03 0 128.012 .035 0 Levee=-1,86.9,1894,-1,117.12,1894 Bank Sta=86.9,117.112 Exp/Cntr=0.1,0.1 Type RM Length L Ch R = 3,99.8 BEGIN DESCRIPTION: Winburn Way END DESCRIPTION: Bridge Culvert--1,0,0,-I Deck Dist Width WeirC Skew NumUp NumDn MinLoCord MaxHiCord MaxSubmerge Is-Ogee 2,72,2.6„14,13,1894„0.95,0,0,0„ 50 80 84 84.01 85.17 89.13 94.51 100 105.49 110.87 114.83 115.99 116 120 1894 1894 1894 1894 1894 1894 1894 1894 1894 1894 1894 1894 1894 1894 0 0 0 1883.49 1886.31 1888.49 1889.62 1890 1889.62 1888.49 1886.31 1883.49 1881.45 0 0 60 65 65.01 66.17 70.13 75.51 81 86.49 91.87 95.83 96.99 97 0 0 1890.6 1890.6 1890.6 1890.6 1890.6 1890.6 1890.6 1890.6 1890.6 1890.6 1890.6 0 0 0 1880.99 1883.81 1885.99 1887.12 1887.5 1887.12 1885.99 1883.81 1880.99 0 BR Coef=-l , 1 , 0,1, 0 ,,,0.8,0,1,0, WSPro=,„, 1 0 0 ,-1 ,-1 , 0, 0, 0 , 0, 0 Type RM Length L Ch R = 1 99.35 ,25,25,25 BEGIN DESCRIPTION: 99+35 END DESCRIPTION: #Sta/Elev= 11 8 1896 8.1 1891 311891.01 45 1890.1 551889.47 64.9 1889.47 65 1890.6 65.1 1879.85 96.9 1879.85 97 1890.6 130 1890.2 #Mann= 2,1 , 0 8 .035 0 65 .013 0 #XS Ineff= 2, 0 0 65 1890.6 97 0 1890.6 Bank Sta=65,97 Exp/Cnv=0.1,0.1 Type RM Length L Ch R = 1 99.10 ,60,50.50 BEGIN DESCRIPTION: 99+10 END DESCRIPTION: #Sta/Elev= 11 -30 1896 -5 1891 311891.01 45 1890.1 551889.47 611889.85 61.1 1879.8 92.9 1879.8 931889.85 1061889.85 106.1 1895 #Mann= 2 ,-1 , 0 -30 .035 0 61 .013 0 Levee=0,,,-1,93,1891.85 Bank Sta=61,93 Exp/Cntr=0.1,0.1 Type RIM Length L Ch R = I 98.60 ,5,5,5 BEGIN DESCRIPTION: 98+60 END DESCRIPTION: #Sta/Elev= 11 211895.96 311891.01 45 1890.1 551889.47 631889.47 681888.85 68.1 1879.76 99.9 1879.76 1001888.85 118 1888.8 118.1 1894 #Mann= 2,1 , 0 APPENDIX E: PROPOSED CONDITIONS HEC-RAS INPUT FILE 9 21 .035 0 68 .013 0 Levee,,,-1,100,1890.85 Bank Sta=68,100 Exp/Cntr=O. 1,0. 1 Type RM Length L Ch R = 1 98.55 ,35,35,35 BEGIN DESCRIPTION: 98+55 END DESCRIPTION: #Sta/Elev= 9 211895.96 311891.01 45 1890.1 551889.47 69.6 1879.76 99.9 1879.76 100 1888.85 118 1888.8 118.1 1894 #Mann= 2 -1 , 0 21 .035 0 55 .03 0 Levee=0-4,100,1890.85 Bank Sta=55,100 Exp/Cntr=0.1,0.1 Type RM Length L Ch R = 1 98.20 ,1,1,1 BEGIN DESCRIPTION: 98+20 END DESCRIPTION: #Sta/Elev= 15 59 1896 601890.55 68.7 1890.17 69.4 1890.13 741887.33 831885.44 92.9 1879.66 93.5 1878.21 1021879.09 110.4 1881.54 114 1885.9 118 1887.89 136.4 1887.83 155 1887.62 155.1 1896 #Mann= 5 ,-1 , 0 59 .03 0 83 .018 0 92.9 .03 0 110.4 .018 0 114 .013 0 Levees,,-1,118,1890.89 Bank Sta=83,118 Exp/Cntt-=O.1,0.1 Type RM Length L Ch R =1 98.19 ,49,49,49 BEGIN DESCRIPTION: 98+19 END DESCRIPTION: #Sta/Elev= 15 59 1896 601890.55 68.7 1890.17 69.4 1890.13 741887.33 831885.44 931879.69 93.5 1878.21 1021877.69 1051879.21 114 1885.9 118 1887.89 136.4 1887.83 155 1887.62 155.1 1896 #Mann= 5 ,-1 , 0 59 .03 0 83 .018 0 93 .03 0 105 .018 0 114 .013 0 Levee=0,,,-1,118,1890.89 Bank Sta=83,118 Exp/Cntr=0.1,0.1 Type RM Length L Ch R = 1 97.70 ,35,30,30 BEGIN DESCRIPTION: 97+70 END DESCRIPTION: #Sta/Elev= 18 67.4 1892.68 67.5 1886.68 72 1886.9 90.4 1877.6 911877.11 93.1 1876.23 95.4 1875.52 1001875.62 104.8 1876.4 1071876.35 108 1877.1 111.3 1879.1 113.4 1884.78 115.7 1886.51 126 1885.95 140 1886 155 1887.09 155.1 1895 #Mann= 2 ,-1 , 0 67.4 .03 0 115.7 .013 0 Levee=0,,,-1,115.7,1887.51 Batik Sta=72,115.7 Exp/Cntr=0.1,0.1 Type RM Length L Ch R = 1 97.40 ,35,35,40 BEGIN DESCRIPTION: 97+40 END DESCRIPTION: #Sta/Elev= 14 541888.55 54.1 1884.5 591884.47 61.1 1884.6 76.3 1877 92.1 1875.51 96 1875.57 100 1875.81 106.1 1876.99 109 1883.99 122 1884.81 138 1884.81 162 1885.07 162.1 1895 #Mann= 4 ,-1 , 0 54 .03 0 61.1 .03 0 109 .018 0 APPENDIX E: PROPOSED CONDITIONS HEC-RAS INPUT FILE 10 122 .13 0 Bank Sta=61.1,109 Exp/Cntr=O. 1,0. 1 Type RM Length L Ch R = 1 97.05 ,35,35,30 BEGIN DESCRIPTION: 97+05 END DESCRIPTION: #Sta/Elev= 14 50 1888 59 1884 72.5 1880.6 81.7 1876 95.6 1874.59 102.6 1874.73 106 1875.08 110.5 1875.74 110.6 1883.92 118 1883.24 122 1883.51 135 1883.36 149 1883.28 149.1 1893 #Mann= 3 ,-1 , 0 50 .03 0 72.5 .03 0 110.5 .013 0 Bank Sta=72.5,110.6 Exp/Cnw=O. 1,0. 1 Type RM Length L Ch R = 1 96.70 ,25,25,25 BEGIN DESCRIPTION: 96+70 END DESCRIPTION: #Sta/Elev= 13 46 1888 56.4 1884.15 73.2 1878.4 80 1875 97.3 1873.46 103 1873.79 106.2 1874.01 108.9 1875.04 109 1882.35 136 1882.5 136.1 1886-11 145 1886.11 145.1 1890 #Mann= 3 ,-1 , 0 46 .045 0 73.2 .03 0 108.9 .013 0 Levees,,-1,109,1884.35 Bank Sta=73.2,109 Exp/Cnu=O. 1,0. 1 Type RM Length L Ch R = 1 96.45 ,10,10,10 BEGIN DESCRIPTION: 96+45 END DESCRIPTION: #Sta/Elev= 15 471882.93 551879.85 70 1879.7 81.4 1874 85.2 1873.92 96.3 1873.42 104.2 1872.47 107 1874.34 109.5 1875.65 115.5 t88143 115.6 1882.21 126.2 1882.9 135 1881.76 138 1881.58 138.1 1887 #Mann= 3 ,-1 , 0 47 .03 0 109.5 .018 0 115.5 .013 0 Levees,,-1,115.6,1884.21 Bank Sta=70,115.6 Exp/Cntr=0.1,0.1 Type RM Length L Ch R = 3,96.40 BEGIN DESCRIPTION: Footbridge END DESCRIPTION: Bridge Culvert--1,0,-1,-1 Deck Dist Width WeirC Skew NumUp NumDn MinLoCord MaxHiCord MaxSubmerge Is-Ogee 2,6,2.6„5,5,1880„0.95,0,0,0„ 69.9 70 98 115.6 115.7 1884.7 1884.7 1887.5 1887.2 1887.2 0 1879.7 1882.5 1882.2 0 70.9 71 99 116.6 116.7 1884.7 1884.7 1887.5 1887.2 1887.2 0 1879.7 1882.5 1882.2 0 BR Coef=-1 , 0, 0, 0 ,,,0.8,-1„l, WSpro=,,,, I 0 0.,,,-l ,-1 ,-1 , 0, 0, 0, 0, 0 Type RM Length L Ch R = 1 96.35 ,40,45,50 BEGIN DESCRIPTION: 96+35 END DESCRIPTION: #Sta/Elev= 15 391882.58 501879.67 671879.35 71.5 1879 77.5 1876 83.7 1875.39 94.8 1873.97 96.9 1873-24 103.1 1873.1-4 108.8 1874.13 116.7 1881.25 121 1881.05 126 1881.35 136 1881.58 136.1 1885 #Mann= 3 ,-1 , 0 39 .03 0 108.8 .018 0 116.7 .013 0 Levee=0,,,-1,116.7,1884.25 Bank Sta=71.5,116.7 APPENDIX E: PROPOSED CONDITIONS HEC-RAS INPUT FILE I 1 Exp/Cntr~.1,0.1 Type RM Length L Ch R = 1 95.90 ,20,25,25 BEGIN DESCRIPTION: 95+90 END DESCRIPTION: #Sta/Elev= 21 32 1885.6 35 18816 451878.44 54.8 t878.38 61.5 1978.01 71.2 1877.7 80.6 1873 92.1 1872.92 96.5 1872.13 1001871.61 102.7 1871.16 106.8 1871.99 108.2 1873 110.1 1878.26 110.8 1878.2 115.5 1878.81 116 1879.32 133 1879.75 133.1 1883.27 140 1883.27 140.1 1885 #Mann= 3 ,-1 , 0 32 .03 0 108.2 .018 0 116 .013 0 Levees.,-1,116,1883.65 Bank Sta=71.2,116 Exp/Cntr=O. 1,0. 1 Type RM Length L Ch R = 1 95.65 ,5,5,5 BEGIN DESCRIPTION: 95+65 END DESCRIP'T'ION: #Sta/Elev= 16 46 1885.7 511880.68 561876.81 621877.27 69.7 1877.75 761877.75 78.5 1877.5 92.3 1870.6 93.1 1870.52 97.6 1871.1 105.2 1870.53 1073 1871.92 117.2 1877.91 117.4 1880.38 132 1878.91 132.1 1885 #Mann= 2 ,-1 , 0 46 .03 0 117.2 .013 0 Levees,,-1,117.4,1883.65 Bank Sta=78.5,117.4 Exp/Cnw=O. 1,0. 1 Type RM Length L Ch R = 1 95.60 ,25,20,15 BEGIN DESCRIPTION: 95+60 END DESCRIPTION: #Sta/Elev= 14 50 1885.7 551880.68 621876.81 671877.27 74.5 1877.75 801877.75 911872.06 93.1 1870.52 97.6 1871.1 109.2 1871.85 110 1873.4 110.5 1880.65 134 1878.58 134.1 1885 #Mann= 2 -T , 0 50 .03 0 110 .013 0 Levee,,,-1,110.5,1883.65 Bank Sta=80,110.5 Exp/Cntr=0.1,0.1 Type RM Length L Ch R = 1 95.40 ,2,2,2 BEGIN DESCRIPTION: 95+40 END DESCRIPTION: #Sta/Elev= 13 70 1886 80.2 1876.94 90.2 1871.94 90.3 1869.92 951870.25 100 1870 106.7 1869.89 107 1871.81 108 1872.16 109 1880.26 117 1880.74 132 1877.16 132.1 1885 #Mann= 2 ,-1 , 0 70 .03 0 108 .013 0 Levee-0,,,-1,109,1883.74 Bank Sta=80.2,109 Exp/Cnw=O. 1,0. 1 Type R.M Length L Ch R = 1 95,38 ,75,68,60 BEGIN DESCRIPTION: 95+38 END DESCRIPTION: #StaiElev= 13 70 1886 90.2 1876.94 90.2 1871.94 90.3 1869.92 951870.25 100 1870 106.7 1869.89 107 1871.81 108 1872.16 116 1876.93 117 1880.74 132 1877.16 132.1 1890 #Mann= 2,-l , 0 70 .03 0 116 .013 0 Levee=0,,,-1,117.1883.74 Bank Sta=80.2.117 APPENDIX E: PROPOSED CONDITIONS HEC-RAS INPUT FILE 12 Exp/Cntr-=O.1,0.1 Type RM Length L Ch R = 1 94.70 ,85,70,60 BEGIN DESCRIP'T'ION: 94+70 END DESCRIPTION: #Sta/Elev= 10 75 1888 85 1878.3 91.2 1878.31 91.5 1870.52 97.9 1868.72 102.4 1869.77 109 1869.32 109.5 1875.03 133 1875.92 133.1 1890 #Mann= 2,-l , 0 75 .03 0 109 .013 0 Bank Sta=91.2,109.5 Exp/Cntr=o.1,0.1 Type RM Length L Ch R = 1 94.00 ,75,75,75 BEGIN DESCRIPTION: 94+00 END DESCRIPTION: #Sta/Elev= 14 62 1884 65 1881 75.1 1881.74 75.2 1869.19 91.2 1868.22 95.1 1965.97 97.8 1965.57 1031866.82 109.3 1866.99 110.1 1870.01 116.5 1871.6 126.1 1877.28 161 1881.99 165 1884 #Mann= 4,-1 , 0 62 .03 0 65 .013 0 75.2 .03 0 116.5 .018 0 #XS Ineff= 2, 0 0 89.1 1884 117 0 1884 Bank Sta=75.1,126.1 Exp/Cntr~0.1,0.1 Type RM Length L Ch R = 3,93.60 BEGIN DESCRIPTION: Main Street END DESCRIPTION: Bridge Culvert--1,0,-I,-1 Deck Dist Width WeirC Skew NumUp NumDn MinLoCord MaxHiCord MaxSubmerge Is-Ogee 13,50,2.6„9,9,1884„0.95,0,0,0„ 75 89 89.1 96.2 102 108.7 117 117.1 161 1881.74 1882.17 1882.17 1882.2 1882.2 1882.15 1882.23 1882.23 1882 0 0 1871.92 1874.09 1874.93 1874.18 1871.6 0 0 0 85 85.1 95 100 105 109 109.1 150 1881.74 1882 1882 1882 1882.2 1882.2 1882.15 1882.15 1880.59 0 0 1870.02 1872-61 1872.93 1872-08 1870.27 0 0 BR Coef=-1 , 1 , 0 ,1, 0 WSPro=,,,, I 0 0 ,-1 ,-1 , 0, 0, 0, 0, 0 Type RIM Length L Ch R = 1 93.25 ,30,50,70 BEGIN DESCRIPTION: 93+25 END DESCRIPTION: #Sta/Elev= 15 35 1885 35.1 1869.87 631869.64 81 1869.6 821867.47 85 1866.4 85.5 1865.97 981864.95 1031864.79 1081865.08 108.5 1866.34 109 1870.72 126 1870.43 130 1880.79 150 1880.59 #Mann= 4,-1 , 0 35 .03 0 81 .025 0 82 .03 0 109 .025 0 #XS Ineff= 2, 0 0 85.1 1879 109 0 1879 Bank Sta=81,109 Exp/Cntr--0.1.0.1 Type RM Length L Ch R = 1 92.75 ,25,30,30 BEGIN DESCRIPTION: 92+75 END DESCRIPTION: #Sta/Elev= 15 73 1885 73.1 1869.42 851869.42 85.1 1867.15 871866.53 931864.59 961863.79 103.5 1863.45 1081864.92 1121868.36 123 1868.43 129 1868.37 145 1869.84 155 1875.89 156 1877 #Mann= 3 ,-1 , 0 73 .013 0 85.1 .03 0 112 .025 0 Bank Sta=85.1,112 APPENDIX E: PROPOSED CONDITIONS HEC-RAS INPUT FILE 13 Exp/Cntr=O. 1,0. 1 Type RM Length L Ch R = I 92.45 ,15,15,15 BEGIN DESCRIPTION: 92+45 END DESCRIPTION: #Sta/Elev= 14 91 1885 91.1 1873.21 921863.98 1011861.59 1031861.85 107 1862.72 107.2 1863.81 109 1864.02 115 1867.53 123 1868.3 128 1868.3 134 1869.5 144 1874.5 145 1877 #Mann= 2 ,-1 , 0 91 .03 0 109 .025 0 Bank Sta=92,109 Exp/Cntr=O. 1,0. 1 Type RM Length L Ch R = 1 ,92.30 ,10,10,10 BEGIN DESCRIPTION: 92+30 END DESCRIPTION: #Sta/Elev= 14 70 1880 70.1 1864 931863.98 951863.21 1001862.16 104.8 1861.8 106 1864.06 113 1868.08 119 1868.11 125 1868.47 135 1869.06 140 1869.06 149 1873.43 150 1877 #Mann= 3 ,-1 , 0 70 .07 0 93 .03 0 113 .025 0 Bank Sta=93,106 Exp/Cntr=0.1,0.1 Type RM Length L Ch R = 1 92.20 ,15,15,15 BEGIN DESCRIPTION: 92+20 END DESCRIPTION: #Sta/Elev= 9 70 1880 70.1 1864 931863.98 951863.21 1001862.16 104.8 1861.8 106 1864.06 108.9 1864.2 140 1880 #Mann= 3 ,-1 , 0 70 .07 0 93 .03 0 108.9 .025 0 Bank Sta=93,106 Exp/Cntr=0.1,0.1 Type RM Length L Ch R = 1 92.05 ,20,29,40 BEGIN DESCRIPTION: 92+05 END DESCRIPTION: #Sta/Elev= 9 95 1880 95.1 1862.67 961862.55 1001862.27 105.1 1863.03 109.5 1863.34 109.6 1863.4 125 1863.4 160 1880 #Mann= 2,-l , 0 95 .03 0 125 .025 0 Bank Sta=95.1,125 Exp/Cnm=0.1,0.1 Type RIM Length L Ch R = 1 91.76 ,8,8,8 BEGIN DESCRIPTION: 91+76 END DESCRIPTION: #Sta/Elev= 12 81 1880 81.1 1863.83 94.1 1862.51 97.5 1861.18 102.4 1861.11 104 1862.7 108.2 1863.8 124 1868.67 128.5 1870.58 164 1870.03 190 1872.6 210 1875 #Mann= 2,1 , 0 81 .03 0 108.2 .018 0 Bank Sta=81.1,128.5 ExpiCntr=O.1,0.1 Type R.M Length L Ch R = 3,91.72 BEGIN DESCRIPTION: Footbridge END DESCRIPTION: Bridge Culvert--1,0,-I.-1 Deck Dist Width WeirC Skew NumUp NumDn MinLoCord MaxHiCord MaxSubmerge Is-Ogee 2, 2.6„4.4.1870.6„0.95,0,0,0„ 50 125 125.1 128 APPENDIX E: PROPOSED CONDITIONS HEC-RAS INPUT FILE 14 1872.84 1872.96 1872.96 1870.58 1871.84 1871.96 0 0 50 125 125.1 128 1872.31 1872.95 1872.95 1870.53 1871.31 1871.31 0 0 BR Coef=1 , 0, 0 „ 0 ,,,0.8,-I„1, WSPro=,,,, 1 0 0,,,,-l ,-1 ,-1 , 0, 0, 0, 0, 0 Type RM Length L Ch R = 1 91.68 ,18,18,18 BEGIN DESCRIPTION: 91+68 END DESCRIP'T'ION: #Sta/Elev= 12 81 1880 81.1 1863.83 94.1 1862.51 97.5 1861.18 102.4 1861.11 104 1862.7 108.2 1863.8 124 1868.67 128.5 1870.58 164 1870.03 190 1872.6 210 1875 #Mann= 2 ,-1 , 0 81 .03 0 124 .018 0 Bank Sta=81.1,128.5 Exp/Cntr-=O.1,0. l Type RM Length L Ch R = 1 91.50 ,45,40,35 BEGIN DESCRIPTION: 91+50 END DESCRIPTION: #Sta/Elev= 15 80.9 1880 811868.67 85.5 1868.67 85.6 1867.77 87.9 1862.53 91.3 1861.95 93.5 1861.38 96.2 1860.76 99.7 1860.9 103.4 1861.41 113.4 1861.5 132.2 1870.9 177 1870 190 1872.6 210 1875 #Mann= 3 ,-1 , 0 80.9 .013 0 85.5 .03 0 132.2 .018 0 Bank Sta=85.5,132.2 Exp/Cntr-0.1,0.1 Type RM Length L Ch R = 1 91.10 ,40,40,40 BEGIN DESCRIPTION: 91+10 END DESCRIPTION: #Sta/Elev= 11 551881.09 89 1876 89.1 1862.09 911859.88 991860.16 119 1860.2 127 1871.03 128 1873.61 160 1870.3 170 1872 190 1875 #Mann= 2 ,-1 , 0 55 .03 0 89 .013 0 #XS Ineff= 2, 0 0 119 0 1873 Bank Sta=89,128 Exp/Cntr-0.1,0.1 Type RM Length L Ch R = 2,90.90 BEGIN DESCRIPTION: Lilthia Way END DESCRIPTION: Bridge Culvert--1,0,-1,-I Deck Dist Width WeirC Skew NumUp NUmDn MinLoCord MaxHiCord MaxSubmerge Is-Ogee 2,37,2.6„3,3,1873„0.95,0,0,0„ 55 86 128 1881.08 1877.23 1877.61 0 0 0 55 86 130 1881.08 1877.23 1877.61 0 0 0 BR Coef=-1 , 1 , 0 ,1, 0,,,0.8,0,1,0, WSPro=,,,, 1 0 0,,,,-l -I -I , 0, 0, 0, 0, 0 Culvert=5,10,30,38.0.02,0.5,1,41,1,1859.88.104,1860.75,104,Culvert#1 ,0,1 Type RM Length L Ch R = 1 90.70 ,50,35 25 BEGIN DESCRIPTION: 90+70 END DESCRIPTION: #Sta/Elev= 12 55 1881 88 1877 88.1 1862.19 92.5 1861.74 1011860.75 119 1861 129 1870 130 1877 144 1870 190 1870 APPENDIX E: PROPOSED CONDITIONS HEC-RAS INPUT FILE 15 260 1872.5 265 1875 #Mann= 2 ,-1 , 0 55 .03 0 88 .013 0 #XS Ineff= 2, 0 0 119 0 1871 Bank Sta=88,130 Exp/Cntr=0. 1,0. 1 Type RM Length L Ch R = 1 90.35 ,25,25,25 BEGIN DESCRIPTION: 90+35 END DESCRIPTION: #Sta/Elev= 13 67 1880 67.1 1869.38 76 1874.67 76.1 1869.29 84 1869 29 90.8 1870.82 90.9 1859.85 1001857.52 120 1858 120.1 1871 1741870.32 1901870.03 260 1872.5 #Mann= 3 ,-1 , 0 67 .03 0 90.8 .013 0 120.1 .02 0 #XS Lid=2 90.8 1870.82 1869.62 120.1 1871 1869.7 Bank Sta=90.8,120.1 Exp/Cntr-0. 1,0. 1 Type RM Length L Ch R. = 1 90.10 ,70,65,65 BEGIN DESCRIPTION: 90+10 END DESCRIPTION: #Sta/Elev= 11 0 1872.5 321869.06 91.7 1869.87 91.8 1860-44 921859.27 100 1859.32 107 1860.23 120 1860.3 120.1 1870.08 147 1871.07 290 1872.5 #NL%m=3,-1,0 0 .03 0 91.7 .02 0 147 .025 0 #XS Lid=2 91.7 1869.87 1868.67 120.1 1870.08 1868.88 Bank Sta=91.7,120.1 Exp/Cntr=0.1,0.1 Type RM Length L Ch R = 1 89.45 ,55,65,70 BEGIN DESCRIPTION: 89+45 END DESCRIPTION: #Sta/Elev= 11 7.7 1869.32 611863.59 88.4 1860.96 94.2 1856.55 991855.64 105.7 1855.5 120 1857 137.6 1865.8 156.8 1865.82 185.8 1865.63 194 1866.53 #Mann= 3 ,-1 , 0 7.7 .03 0 88.4 .03 0 137.6 .02 0 Bank Sta=88.4,137.6 Exp/Cntr=0.1,0.1 Type RM Length L Ch R. = 1 88.80 ,40,40,40 BEGIN DESCRIPTION: 88+80 END DESCRIPTION: #Sta/Elev= 15 23.4 1868.31 38.8 1863.94 50.2 1863.5 84.2 1860.8 93.7 1854.85 96.1 1853.74 103.5 1854.03 105.5 1857.67 115 1859.15 123.2 1864.11 135.5 1864.22 140.3 1864.67 146 1864.43 162.2 1864.98 180 1866 #Mann= 3 ,-1 , 0 23.4 .03 0 84.2 .03 0 123.2 .02 0 Bank Sta=84.2,123.2 Exp/Cntr=0.1,0.1 Type RM Length L Ch R. = 1 88.4 ,85,80,30 BEGIN DESCRIPTION: 88+40 END DESCRIPTION: #Sta/Elev= 15 0 1865.43 44.2 1863.47 80 1860.22 92 1855.11 94.1 1853.92 100 1853.73 104.8 1854.5 107.9 1855.8 120 1862.28 128.1 1863.33 141.2 1863.18 152 1862.87 155 1863.06 170 1865 190 1867.5 #Mann= 3 ,-1 , 0 APPENDIX E: PROPOSED CONDITIONS HEC-RAS INPUT FILE 16 0 .03 0 80 .03 0 120 .02 0 Bank Sta=80,120 Exp/Cntr--O. 1,0. 1 Type RM Length L Ch R = 1 87.60 ,35.35,50 BEGIN DESCRIPTION: 87+60 END DESCRIPTION: #Sta/Elev= 18 30 1867 30.1 1864.33 50 1861 69.038 1860.6 69.745 1853.83 72.57301 1852.07 75.0475 1852.02 77.522 1851.15 85.299 1851.99 89.1875 1851.97 94.49001 1852.32 105.802 1852.53 112.165 1852.97 114.286 1853.29 122.063 1862.16 160 1862.5 175 1865 185 1867.5 #Mann= 3 ,-1 , 0 30 .025 0 69.038 .03 0 122.063 .015 0 #XS Ineff= 2, 0 0 77 1861 107 0 1862.1 Bank Sta=69.038,122.063 Exp/Cntr=0.1,0.1 Type RM Length L Ch R = 2,87.5 BEGIN DESCRIPTION: Water Street END DESCRIPTION: Bridge Culvert--1,0,-1,-1 Deck Dist Width WeirC Skew NumUp NumDn MinLoCord MaxHiCord MaxSubmerge Is-Ogee 2,31,3. l „4,3,1861 „0.95,0,0,0„ 68 94.5 119.9 122 1860.6 1861.1 1862.16 1862.16 0 0 0 0 60 87 113 1860.8 1861.1 1862 0 0 0 BR Coef=-1 , I , 0 ,1, 0 ,,,0.8,-1,1,0, WSPm=,,,, 1 0 0 ,-1 ,-1 , 0, 0, 0, 0, 0 Culvert=5,7,30,35,0.02,0.5,1,41,1,1852,92,1851,86,Culvert#1 ,0,2 Type RM Length L Ch R = 1 87.25 ,35,50,50 BEGIN DESCRIPTION: 87+25 END DESCRIP'T'ION: #Sta/Elev= 14 10 1866 10.1 1864.33 59.662 1860.8 61.783 1857.79 66.025 1851.28 68.146 1849.2 72.7415 1851.43 76.63 1851.79 81.2255 1851.34 83.7 1852.03 105 1852 113 1862 120 1862 180 1865 #Mann= 2,-l , 0 10 .03 0 113 .02 0 #XS Ineff= 2 , 0 0 71 1859 101 0 1860 Bank Sta=59.662,113 Exp/Cntr~. 1,0. 1 Type RM Length L Ch R = 1 86.75 ,70,90,105 BEGIN DESCRIPTION: 86+75 END DESCRIPTION: #Sta/Elev= 10 89 1880 89.1 1856.17 90.5 1851.66 921851.35 1001849.24 103.1 1849.78 107 1851.22 112.5 1853.14 126.5 1856.11 145 1860 #Mann= 3 ,-1 , 0 89 .013 0 89.1 .03 0 112.5 .045 0 #XS Ineff= 2, 0 0 89.1 1856.17 112.5 01853.14 Bank Sta=89.1,112.5 Exp/Cntr=0.1.0.1 Type RM Length L Ch R = 1 85.85 ,80,80,80 BEGIN DESCRIPTION: 85+85 END DESCRIPTION: #Sta/Elev= 17 85 1854.7 85.1 1849.04 87.8 1848.02 91 1847.4 93.1 1845.52 93.7 1844.82 96.2 1844.57 98.8 1844.61 100.9 1844.03 103.8 1845.63 APPENDIX E: PROPOSED CONDITIONS HEC-RAS INPUT FILE 17 107.1 1846.02 110.7 1846.63 114.2 1846.36 115.9 1846.39 118.9 1846.7 119.5 1848.51 129.5 1858.51 #Mann= 3 ,-1 , 0 85 .045 0 87.8 .03 0 119.5 .03 0 Bank Sta=91,119.5 Exp/Cntr=O. 1,0. 1 Type RM Length L Ch R = 1 85.05 ,90.90,90 BEGIN DESCRIPTION: 85+05 END DESCRIPTION: #Sta/Elev= 13 -51853.72 6.5 1854.26 21.2 1854.07 80.3 1850.41 86.7 1846.5 901845.66 951844.66 1001843.87 101.8 1844.55 1071845.71 114.6 1846.49 124 1848.16 130 1853.37 #Mann= 4 ,-1 , 0 -5 .013 0 21.2 .045 0 86.7 .03 0 114.6 .03 0 Bank Sta=86.7,124 Exp/Cntr=0.1,0.1 Type RM Length L Ch R = 1 84.15 ,60,60,60 BEGIN DESCRIPTION: 84+15 END DESCRIP'T'ION: #Sta/Elev= 12 221851.97 551850.57 74.5 1848.42 80.6 1847.02 89.4 1846.58 95 1843.27 100 1842.52 102.5 1843.69 107 1846.68 116 1845.07 123 1844.96 145 1851.34 #Mann= 4,-1 , 0 22 .013 0 55 .045 0 74.5 .03 0 107 .045 0 Bank Sta=89.4,107 Exp/Cntr---0.1,0.1 Type RM Length L Ch R = 1 83.55 ,110,100,80 BEGIN DESCRIPTION: 83+55 END DESCRIPTION: #Sta/Elev= 12 -20 1852.5 20 1852.5 60 1850 68.5 1847.95 84.5 1845.65 931841.85 95.4 1841.48 1061840.48 1071842.14 1201846.78 165 1846.89 180 1860 #Mann= 4 ,-1 , 0 -20 .013 0 20 .045 0 84.5 .03 0 120 .045 0 Bank Sta=84.5,120 Exp/Cntr-0. 1,0. 1 Type R-M Length L Ch R = 1 82.55 ,55,60,70 BEGIN DESCRIPTION: 82+55 END DESCRIPTION: #Sta/Elev= 14 -20 1850.5 20 1850.5 50 1850 841846.01 92.3 1839.7 95 1838.57 101.6 1838.31 107 1839.07 108 1839.59 110 1841.34 125 1843.07 140 1844.76 160 1855 180 1860 #Mann= 4,-1 , 0 -20 .013 0 20 .045 0 92.3 .03 0 110 .045 0 Bank Sta=84.110 Exp/Cntr=0.1,0.1 Type RM Length L Ch R = 1 81.95 ,45,45,45 BEGIN DESCRIPTION: 81+95 END DESCRIPTION: #Sta/Elev= 17 -50 1848.5 -30 1848.5 10 1848.5 84.4 1844.38 881837.88 94.5 1837.02 102 1837.35 103.5 1837.66 110 1837.62 112.5 1837.58 118 1837.53 131 1842.33 148.5 1843.77 155 1846.39 160 1850 170 1852 180 1855 #Mann= 5 ,-1 , 0 APPENDIX E: PROPOSED CONDITIONS HEC-RAS INPUT FILE 18 -50 .03 0 -30 .013 0 10 .045 0 84.4 .03 0 131 .025 0 Bank Sta=84.4,131 Exp/Cntr=O. 1,0. 1 Type RM Length L Ch R = 5,81.90 BEGIN DESCRIPTION: dragons teeth END DESCRIPTION: #Inline Weir SE= 20 86.1 0 86.2 1842.76 88.7 1842.76 88.8 0 93.9 0 941841.65 96.5 1841.65 96.6 0 101.9 0 1021841.78 104.5 1841.78 104.6 0 109.9 0 1101841.79 112.5 1841.79 112.6 0 117.9 0 1181842.29 1311842.33 1501842.33 rW Dist,WD,Coef,Skew,MaxSub,Min_EI,Is_Ogee,SpillHt DesHd 1,2.5,3„0.95„ 0 ,,,0,0, Type RM Length L Ch R = 1 81.50 ,40.40,40 BEGIN DESCRIPTION: 81+50 END DESCRIPTION: #Sta/Elev= 12 -200 1850 51845.67 591846.46 89.5 1836.19 921835.72 100.8 1835.52 109 1835.78 109.1 1836.36 117 1845.88 141 1847.01 145 1851.36 177 1852.12 #Mann= 1 ,-1 , 0 -200 .03 0 #XS Ineff= 2, 0 0 89.5 1847 109.1 0 1847.5 Bank Sta=59,117 Exp/Cntr=O. 1,0. 1 Type RM Length L Ch R = 2,81.40 BEGIN DESCRIPTION: Van Ness END DESCRIP'T'ION: Bridge Culvert--1,0,-1: I Deck Dist Width WeirC Skew NumUp NUtnDn MinLoCord MaxHiCord MaxSubmerge Is-Ogee 2,36,2.6„4,4,1845.67„0.95,0,0,0„ 5 89.5 117 177 1845.67 1847.1 1847.69 1852.12 0 0 0 0 -10 90 112 157 1844.18 1847.1 1847.64 1848.85 0 0 0 0 BR Coef=-1 , 1 , 0,1, 0 ,,,0.8,0,1,0, WSpro=,,,, 1 0 0 ,111-1 ,-1 ,-1 , 0, 0, 0, 0, 0 Culvert=5,7.54,20,43,0.02,0.5,1,41,1,1835.65,100,1835.4,100,Culvert#1 , 0.2 Type RM Length L Ch R = 1 81.10 ,20,20,20 BEGIN DESCRIP'T'ION: 81+10 END DESCRIPTION: #Sta/Elev= 10 -200 1850 -101844.18 431845.58 82.5 1845.4 901835.39 100 1835.4 110 1835.37 115 1846.78 157 1848.85 197 1851.83 #Mann= 1 -t , 0 -200 .03 0 #XS Ineff= 2, 0 0 90 1845 110 0 1846 Bank Sta=82.5,115 Exp/Cntr=0.1,0.1 Type R,.I Length L Ch R = 1 80.90 ,40,40,40 BEGIN DESCRIPTION: 80+90 END DESCRIPTION: #Sta/Elev= 12 -200 1850 -101844.18 431845.58 82.5 1845.4 901834.85 96 1834.19 102 1834.04 109 1834.12 1301840.564 157 1848.85 197 1851.83 198 1860 #Mann= 2 ,-1 , 0 -200 .03 0 -10 .03 0 APPENDIX E: PROPOSED CONDITIONS HEC-RAS INPUT FILE 19 #XS Ineff= 2, 0 0 91 1857 109 0 1858 Bank Sta=82.5,130 Exp/Cntr=0.1,0.1 Type RM Length L Ch R = 3,80.7 BEGIN DESCRIPTION: SPRR END DESCRIPTION: Bridge Culvert--1,0,-1,-1 Deck Dist Width WeirC Skew NumUp NumDn MinLoCord MaxHiCord MaxSubmerge Is-Ogee 2,37,2.6„8,8,1857.24„0.95,0,0,0„ -200 0 90 91 100 109 110 200 1857 1857.24 1858.16 1858.16 1858.16 1858.16 1858.16 1859.19 0 0 0 1845.47 1849.92 1843.12 0 0 0 92 93 102 108 111 113 200 1857.24 1858.16 1858.16 1858.16 1858.16 1858.16 1858.16 1859.19 0 0 1844.6 1849.05 1847.64 1834.77 0 0 BR Coef=-1 , 1 , 0,1, 0 ,,,0.8,0,1,0, WSPro=,,,, 1 0 0 ,-1 ,-1 , 0, 0, 0, 0, 0 Type RM Length L Ch R = 1 80.5 ,35,35,35 BEGIN DESCRIPTION: 80+50 END DESCRIPTION: #Sta/Elev= 10 371856.63 501851.376 751841.271 92 1834.4 1001833.81 108 1834.23 111 1834.77 130 1841 194 1857.64 196 1860 #Mann= 1 ,-1 , 0 37 .03 0 #XS Ineff= 2, 0 0 92 1855 111 0 1855 Bank Sta=75,130 Exp/Cntt=0.1,0.1 Type RM Length L Ch R = 1 80.15 ,1,1,1 BEGIN DESCRIPTION: 80+15 END DESCRIPTION: #Sta/Elev= 9 781841.76 921833.87 104.5 1833.44 1071833.88 1121837.72 122.5 1840.32 153.5 1842-01 1851840.26 300 1842.5 #Mann= 3 ,-1 , 0 78 .03 0 112 .025 0 122.5 .013 0 Bank Sta=78,112 Exp/Cntr=0.1,0.1 Type RM Length L Ch R = 1 80.14 ,110,109,110 BEGIN DESCRIPTION: 80+14 END DESCRIPTION: #Sta/Elev= 9 781841.76 921833.87 97.5 1830.43 1071833.88 1121837.72 122.5 1840.32 153.5 1842.01 1851840.26 300 1842.5 #Mann= 3 ,-1 , 0 78 .03 0 112 .025 0 153.5 .013 0 Bank Sta=78,112 Exp/Cntr=0.1,0.1 Type RM Length L Ch R = 1 79.05 ,65,65,65 BEGIN DESCRIPTION: 79+05 END DESCRIPTION: #Sta/Elev= 9 73.6 1836.84 90.2 1830.42 961829.36 1011829.16 108 1829.9 115.5 1834.57 127 1834.1 183 1834.41 330 1837.5 #Mann= 3 ,-1 , 0 73.6 .03 0 115.5 .025 0 127 .013 0 #XS Ineff= 2.0 0 73.6 1836.84 115.5 01834.57 Bank Sta=73.6.115.5 Exp/Cntr--O. 1,0. 1 APPENDIX E: PROPOSED CONDITIONS HEC-RAS INPUT FILE 20 Type F-M Length L Ch R = 1 78.40 ,80,90,95 BEGIN DESCRIPTION: 78+40 END DESCRUMON: #Sta/Elev= 12 621834.99 831835.65 951828.48 971827.41 99.5 1827.21 104 1827.76 108 1828.2 116 1832.73 153.5 1832.61 211 1833.38 330 1835 370 1837.5 #Mann= 4 -1 , 0 62 .03 0 95 .03 0 116 .025 0 153.5 .013 0 #XS Ineff= 2, 0 0 831835.65 116 01832.73 Bank Sta=83,116 Exp/Cntr-0.1,0.1 Type RM Length L Ch R = 1 77.5 ,75,75,90 BEGIN DESCRIPTION: 77+50 END DESCRIPTION: #Sta/Elev= 14 67.5 1833.76 791834.14 921826.57 961825.14 101.5 1825.17 105 1825.69 107 1826.56 115 1830.79 135 1829.98 163 1830.39 1831831.13 210 1832.5 400 1835 450 1837.5 #Mann= 3 ,-1 , 0 67.5 .03 0 115 .025 0 135 .013 0 #XS Ineff= 2, 0 0 791834.14 115 01830.79 Bank Sta=79,115 Exp/Cntr~-.1,0.1 Type RM Length L Ch R = 1 76.75 ,70,75,80 BEGIN DESCRIPTION: 76+75 END DESCRIPTION: #Sta/Elev= 12 6681831.66 791831.73 91 1824.7 951823.25 1001823.56 103.2 1823.6 110 1824.46 121.5 1829.23 135 1833.19 179 1828.8 199 1832 205 1831.88 #Mann= 3 ,-1 , 0 66.5 .03 0 121.5 .025 0 135 .013 0 Bank Sta=79,121.5 Exp/Cntr=0.1,0.1 Type RM Length L Ch R = 1 76.00 ,50,45,25 BEGIN DESCRIPTION: 76+00 END DESCRIPTION: #Sta/Elev= 14 0 1832 40 1832 76.5 1829.73 86.5 1827.21 92 1823.1 94 1821.58 101 1821.81 102 1823.15 106.5 1823.25 121 1822.98 137 1829.39 147 1825.68 190 1826.71 231 1837.74 #Mann= 4 ,-1 , 0 0 .013 0 40 .03 0 121 .025 0 147 .013 0 Bank Sta=86.5,121 Exp/Cntr=0.1,0.1 Type RM Length L Ch R = 1 75.55 ,65,65,65 BEGIN DESCRIPTION: 75+55 END DESCRIPTION: #StaiElev= 13 -50 1832.5 0 1830 40 1829.5 471828.31 861819.08 100 1819.08 114 1819.08 127 1827.74 143 1827.79 157 1827.87 1841828.19 2081828.62 250 1832 #Mann= 5 >-1 , 0 -50 .03 0 0 .013 0 47 .03 0 127 .025 0 157 .013 0 #XS Ineff= 2, 0 0 861828.31 114 01827.74 Bank Sta=47,127 Exp/Cntr=0.1,0.1 APPENDIX E: PROPOSED CONDITIONS HEC-RAS INPUT FILE 21 Type RM Length L Ch R = 2,75-25 BEGIN DESCRIPTION: Hersey Street END DESCRIPTION: Bridge Culvert--1,0,-1,-1 Deck Dist Width WeirC Skew NumUp NumDn MinLoCord MaxHiCord MaxSubmerge Is Ogee 5,55,2.6„10,11,1827.74„0.95,0,0,0„ 47 75 92 95.1 97 102 104 106 109 126 1828.31 1828.7 1829.87 1829.87 1829.87 1829.9 1829.9 1830 1830 1827.74 0 0 0 0 0 0 0 0 0 0 33 61 81 89 93 95 100 102 104 107 118 1827.28 1828.25 1828.43 1828.93 1828.75 1828.75 1828.75 1828.75 1828.75 1828.75 1828.23 0 0 0 0 0 0 0 0 0 0 0 BR Coef=-1 , 1 , 0,1, 0 ,,,0.8,0,1,0, WSPro=,,,, 1 0 0 ,,,,-1 ,-1 ,-1 , 0, 0, 0, 0, 0 Culvert=5,9.5,28,55,0.024,0.5,1,41,1,1819.08,100,1816.12,100,Culvert#1 ,0,5 Type RM Length L Ch R = 1 74.9 90,110,130 BEGIN DESCRIPTION: 74+90 END DESCRIPTION: #Sta/Elev= 12 0 1830 441827.58 561827.86 811826.89 861816.12 100 1816.12 114 1816.12 117 1828.23 120 1826.19 182 1826.1 2231826.78 250 1828 #Mann= 1 ,-1 , 0 0 .03 0 #XS Ineff= 2, 0 0 86 1822 114 0 1822 Bank Sta=81,117 Exp/Cntr~.1,0.1 Type RM Length L Ch R = 1 73.80 ,0,0,0 BEGIN DESCRIPTION: 73+80 END DESCRIPTION: #Sta/Elev= 13 431827.22 531824.77 701818.08 891816.28 901815.36 941815.46 991815.96 1061816.11 109 1816.6 1161820.42 1401820.61 173 1821.3 300 1821.3 #Mann= I ,-1 , 0 43 .03 0 Bank Sta=70,116 Exp/Cntr=O. 1,0. 1 Chan Stop Cuts=-1 APPENDIX FOUR to Ashland Creek Flood Restoration Project Final Report November 3, 1997 Ashland Creek Environmental Report October 31, 1997 Submitted to: City of Ashland Ashland, Oregon Submitted by: Fishman Environmental Services 434 NW Sixth Avenue Portland, OR 97209-3600 (503) 224-0333 ASHLAND CREEK FLOOD RESTORATION PROJECT APPENDIX FOUR ENVIRONMENTAL REPORT Prepared by: Fishman Environmental Services and Watershed Applications, Ltd. Prepared for: Otak, Inc. October 31, 1997 FES 97037-02 P `,PROJECn7800\7844\FLDREPORWPPENDD\WOZRPT.FNL APPENDIX FOUR TABLE OF CONTENTS INTRODUCTION 1 1 AQUATIC RESOURCES 1 2 BRIDGE REPLACEMENT RECOMMENDATIONS 7 3 STREAM CHANNEL REHABILITATION 10 4 PROJECT STAFF 19 LIST OF FIGURES Figure 1: Ashland Creek Study Reach 23 Figure 2: Lithia Park Features 24 Figure 3: Boulder Weir and Boulder Ramp Treatments 25 Figure 4: Grouted Stone Bank Treatment 26 Figure 5: Low Boulder Bank Treatment 27 Figure 6: Possible Retaining Wall Configuration Along Winburn Way 28 LIST OF TABLES Table 1: ASHLAND CREEK WATER QUALITY DATA 6 Table 2: LITHIA PARK BRIDGE REPLACEMENT MATRIX 9 Table 3: RECOMMENDED STREAM CHANNEL IMPROVEMENTS 20 0 o Ashland Creek Environmental Report `j Page Four-i INTRODUCTION This report consists of three major sections: 1) Aquatic Resources; 2) Bridge Replacement Recommendations, and 3) Stream Channel Rehabilitation. Section 1 discusses the condition of aquatic habitat observed during the summer of 1997, and provides a summary of information available for fish populations, aquatic invertebrates and water quality. Section 2 presents findings and recommendations related to bridge locations in Lithia Park. Section 3 presents findings and recommendations concerning channel conditions, including stream information pertaining to bank condition, fish habitat and passage, recreation and aesthetics. Figure 1 shows the Ashland Creek study area and indicates station numbers along the creek. Figure 2 shows features in the Lithia Park portion of the study area. All recommendations made in this report need to be evaluated for feasibility by City and Park staff. 1 AQUATIC RESOURCES Methods Aquatic resources in Ashland Creek were surveyed on April 23 and July 10, 1997 by Paul Fishman and Steve Johnson of Fishman Environmental Services. Visual observations of fish inhabiting pool areas and identification of potential barriers to fish movement were made during the July 10 field visit. Qualitative observations of benthic fauna and substrates were made in several areas between the Hersey Street Bridge and the Parks and Recreation offices in Lithia Park during the initial field visit and from the Main Street Bridge upstream to the Granite Street reservoir during the second visit. Water quality data were collected from sites near the major bridge crossings as well as within Lithia Park. Findings The severe storms and consequent flooding in January 1997, in addition to causing extensive property damage in the downtown area of Ashland, also led to mobilization and transportation of large volumes of fine to coarse granitic sands released from slides and erosion of streambanks. Much of this material became embedded in the interstices between the larger gravel and cobble substrates found throughout the study reach extending from the Hersey Street Bridge to the Parks and Recreation offices in Lithia Park. Despite the sedimentation resulting from these storm events, some salmonid fish spawning did occur within the watershed during the winter months. It is not known whether the observed juvenile salmonids emerged from Ashland Creek or less affected tributary streams. Although most of the potential spawning areas observed in the study area appeared to be highly embedded with sand, some salmonid spawning was successful as evidenced by the presence of juvenile (young-of-the year) salmonids. Young-of-the-year salmonids, most of which appeared to be rainbow/steelhead trout (Oncorhynchus mykiss), were observed in most suitable O 0 Ashland Creek Environmental Report 7 Appendix Four Page 1 rearing areas, particularly within the Lithia Park reach. Rainbow/steelhead fry typically emerge from March through June. In addition, some larger trout in the 10-14 inch length range were also observed in pool areas. These are likely either resident rainbow or cutthroat (Salmo clarki) trout. A report on the effects of long-term siltation on aquatic organisms in Ashland Creek (Hegdahl 1988) included fish trapping at several locations in the Lithia Park reach. No fry were collected during this study. However, 80 juvenile steelhead were trapped, most likely age 1+ juveniles that emerged the previous spring. The report suggests that these fish are migratory steelhead. The length distribution of these fish would also suggest that rainbow trout/steelhead do rear in Ashland Creek throughout the year. Mike Evenson, District Biologist for Oregon Department of Fish and Wildlife (ODFW), indicated that little fish survey work has been done by ODFW on Ashland Creek. There are no established goals for fish production in Ashland Creek. A 1977 survey of the lower five miles of Ashland Creek (Bear Creek to the Granite Street reservoir) produced an estimate of 50 summer steelhead. ODFW presently has hatch boxes along Ashland Creek where they raise coho salmon (Oncorhynchus kisutch) eggs from the Cole Rivers Hatchery (Rogue River) as part of the Salmon and Trout Enhancement Program (STEP). They also occasionally release "excess" adult coho from Cole Rivers Hatchery into Ashland Creek. There does not appear to be a program to monitor the creek for returning adult fish.' The lower reaches of Ashland Creek make up 19% of steelhead trout spawning habitat in the Bear watershed according to the 1995 Bear Watershed Analysis (USDA Forest Service 1995). Rainbow trout were observed in the East and West Forks of Ashland Creek (above Hosler Dam) in approximately the first mile of stream habitat. The rainbow trout are probably remnant populations of past steelhead runs before Hosler Dam was constructed in 1928. Hosler Dam is located 4.3 miles upstream from the mouth of Ashland Creek. The East Fork and West Fork of Ashland Creek have healthy resident cutthroat trout populations. In both of these streams some hybridization between rainbow and cutthroat trout has occurred. Historical sea-run cutthroat trout presence has been questioned; currently, they are not present in the watershed. Coho salmon historically spawned and reared in the tributaries and main stem of Bear Creek, but today the population of coho salmon is significantly reduced in the watershed. Urbanization, agriculture, water withdrawals, loss of stream/floodplain connectivity, channel simplification, and water quality issues inhibit the recovery of coho salmon. Information on other fish species that occur in Ashland Creek is a by-product of investigation of salmonids in the Bear watershed. The Pacific lamprey, a candidate species for listing as threatened under the Endangered Species Act (ESA), spawn in the upper mainstem of Bear Creek and 1 personal communication, Mike Evenson and Chuck Fustich, ODFW, May, 1997. O Ashland Creek Environmental Report Appendix Four Page 2 tributaries. The lower watershed contains populations of warmwater fish including large and small mouth bass, black crappie, bluegill, catfish; brown bullhead, yellow perch, carp, and goldfish (USDA Forest Service 1995). It is not known whether these species reside in lower Ashland Creek. Generally, the habitat and flow conditions found in Ashland Creek are not preferred by these species. Two concrete dam/diversion structures present significant barriers to fish passage through the Lithia Park reach. Both structures would likely be classified as multiple falls since a fish has several routes from which to choose. The first (downstream-most) structure has a 4.5-foot drop from the top of the structure to the downstream water surface. The average plunge pool depth of 2.5 feet is inadequate to allow easy upstream access by migratory fish. It has been suggested that a ratio of 1:11/a (fall height/plunge pool depth) provides the best standing wave for leaping. This particular structure is likely passable during certain flow conditions where the differential elevation and water velocities are within the swimming and leaping capabilities of the species moving upstream, but presents a formidable barrier during low flows. The upstream-most concrete dam/diversion structure is not as high as the other structure (2.5 feet), but also presents a passage problem during low flow conditions. There are two main considerations in determining whether these structures provide adequate passage opportunities in their current condition. First, plunge pool depth. Aaserude (1984) found that the following conditions are necessary to provide optimum leaping conditions in plunge pools: 1) depth of penetration of the falling water should be less than the depth in the plunge pool and 2) depth of the plunge pool must be similar to or greater than the length of the fish attempting to pass. Secondly, landing conditions must be carefully considered. It is important to determine the landing conditions at the crest of the obstacle for a range of flow conditions. If depths are not sufficient at the upstream end during landing, the fish may lose momentum and be swept back downstream. There must be sufficient depth and velocity must be low enough to allow the fish to propel itself upstream. These issues will need to be investigated further if improved fish passage is determined to be a stream improvement goal. It is likely that engineered fish ladders or a series of smaller jump pools are necessary to make these waterfall structures more passable for adult salmonids. Rock and gravel have accumulated on the upstream side of each of these structures, so that water depth is the same as depth over the spillway. This is also a concern for fish passage. Invertebrate fauna observed in lower Ashland Creek during the two 1997 field visits included: diptera (midge and black flies); ephemeroptera (mayflies); odonata (dragonflies); trichoptera (caddisflies); oligochaetes (segmented worms); and gastropods (snails). These taxa comprise an invertebrate community similar to the taxa found in 1988 (Hegdahl 1988). The aquatic invertebrate community did not appear to be particularly dense in most areas. The round cobble and sand substrates that dominate Ashland Creek are easily moved by increases in flow volume and velocity, making it difficult for many taxa to colonize these areas. The taxa that do occur in Ashland Creek are characteristic of a relatively healthy system and include both highly adaptive and water quality- sensitive taxa. 0 0 . 9C1," Ashland Creek Environmental Report Appendix Four Page 1 Water quality in Ashland Creek was sampled using an ICM Aquacheck in situ meter. Parameters included temperature, dissolved oxygen, pH, and conductivity. Water samples were also collected during some field visits and analyzed for turbidity at the Fishman Environmental Services office. Results of water quality sampling are presented in Table 1. Dissolved oxygen readings taken on August 7, 1997 were considerably lower than other values from the same trip. Air temperatures were particularly warm during the afternoon when sampling occurred. Assuming these values are not an equipment error, they indicate that warm water temperature and low dissolved oxygen levels could be a problem for fish during hot summer periods. In general, water temperatures above the mid-50s (°F) and dissolved oxygen concentrations below 5 ppm are not favorable for steelhead. Additional monitoring of stream temperature and dissolved oxygen is recommended during hot-weather summer low flows. Seasonal low oxygen levels could limit the habitat value of Ashland Creek for salmonids. It is interesting to note that the downstream water quality stations, such as the Winburn Way, Main Street, and Hersey Street Bridge areas, consistently had higher conductivity values than the upstream stations through Lithia Park. Several factors may be responsible for this difference including dissolved nutrient ions from local and agricultural runoff and possibly the addition of the Lithia spring waters that enter Ashland Creek near the bandshell. Recommendations Fish production goals for Ashland Creek are not clearly defined by ODFW and there may be room for improvements to fish habitat and populations through a number of actions. Initially, we recommend that representatives of the City meet with ODFW staff to determine if a local management/monitoring program could be developed to assist the agency's efforts. This program could include such tasks as visual spawning surveys during peak months, observation of the potential passage barriers within Lithia Park during fish (steelhead) migration, and summer monitoring of temperature and dissolved oxygen to determine if water quality is acceptable for salmonid residence in the lower creek. Information gathered through this initial program could be used to identify future improvement projects, such as removal of passage obstacles, if necessary, (building smaller jump structures to facilitate fish passage) or establishment of minimum flow conditions to maintain water quality in Ashland Creek. Volunteer efforts could be coordinated with Southern Oregon University and provide a long-term source of vital information. 0 Ashland Creek Environmental Report Appendix Four Page 4 References Aaserude, R.G. 1984. New concepts in fishway design. M.S. Thesis, Dept. Civil and Environmental Engineering, Washington State University. Hegdahl, D. 1988. The delayed long term effects of heavy siltation from the cleaning of Reeder Reservoir (Jackson County, Oregon) on aquatic organisms living in Ashland Creek. Powers, P.D. and J.F. Orsborn. 1985. Analysis of Barriers to Upstream Fish Migration: An Investigation of the Physical and Biological Conditions Affecting Fish Passage Success at Culverts and Waterfalls. Bonneville Power Admin. Fisheries Project No. 82-14. Contract DE- A179-82BP36523. USDA Forest Service 1995. 1995 Bear Watershed Analysis. Ashland Ranger District. Rogue River National Forest. 0 Ashland Creek Environmental Report Appendix Four Page 5 TABLE 1: ASHLAND CREEK WATER QUALITY DATA FES 97037.• ASHLAND CREEK FLOOD RESTORATION PROJECT WATER QUALITY DATA TIME DO DO COND TURB DATE STATION hr TEMP C TEMP F m %sat H NTU Jul 10, 97 Main St. 1100 11. 53.1 10 7.6 67.9 Jul 10, 97 Winburn 1350 13.3 55.9 9.61 71 65.3 0.82 Jul 11,97 Hersey 852 11 51.8 -10 7.5 70. 1.78 Reeder Jul 11, 97 Res" 1031 14.4 57.9 8.2 7.4 44.6 Au 07, 97 _Hersey 1333 18.2 64.8 3.3 34 7.2 164 0.85 Au 07, 97 Winburn 1340 18.9 66.0 2.9 30 7.2 15 Au 07, 97 Pioneer 134 17. 63.9 3.6 36 7.1 71.8 1.02 Au 08, 97 Res. inflow 824 13.6 56.5 9. 90 7.2 62.5 Au 08, 97 below Res. 828 14.4 57.9 9. 93 6.6 63.1 Au 08, 97 above TID 83 14.4 57.9 10.5 100 6.9 68.8 Au 08, 97 TID inflow 839 16.5 61. 10.6 105 7.1 58.5 Au 08, 97 bridge site-* 844 15.0 59.0 10.3 100 7.2 68.3 Au 08, 97 Pioneer 853 15.0 59.0 10.1 98 7.1 68.8 Au 08, 97 Winburn 859 15.1 59.2 10.2 100 7.2 114 Au 08, 97 Winburn 910 air 16.2 61.2 Se 15,97 Hersey 735 12.1 53.8 10.6 98 7.9 106 Se 15, 97 Winburn 750 12.2 54.0 11 101 7. 111 Se 15, 97 Pioneer 810 12.3 54.1 10.1 95 7.8 75. dnstr TID Se 15,97 inflow 825 12.4 54.3 9.9 91 7. 75.9 upstr TID Se 15, 97 inflow 830 12.6 54. 10.1 94 7. 76.2 dnstr Se 15,97 Reservoir 850 12.9 55.2 10.2 93 7.6 68.4 upstr Se 15, 97 Reservoir 900 12. 54.9 9.3 86 7.9 71.6 data collected by: method. g:I19971970371phase4Iwgdata P. Fishman A ua-Check wb2 TABLE NOTES: Conductivity in micromhos Shallow inflow to reservoir First washed-out bridge downstream of TID inflow Res. = Swimming reservoir 0 Ashland Creek Environmental Report Appendix Four Page 6 2 BRIDGE REPLACEMENT RECOMMENDATIONS Introduction This section of the Ashland Creek Environmental Report contains information about the bridges over Ashland Creek in Lithia Park. The information and recommendations are a result of field assessment of the stream corridor conducted during the summer, following the January 1997 flood event. The information is intended to provide baseline information and recommendations that the Park Commission and the community can use for making decisions concerning the replacement of bridges that were destroyed in the January 1997 flood. The information on park bridges is summarized in the accompanying matrix (Table 2) and referenced to the text in this section of the report (Section 2). Maps of the stream corridor showing bridge locations are included at the end of the report (Figures 1 and 2). For this discussion, bridges are numbered consecutively upstream. The station numbers 'are approximate and can be determined from the figures included at the end of this report. "Status" refers to the presence or absence of an operational bridge span at a particular bridge location indicated by abutments. "Park priority" refers to the level of need for the bridge indicated by park staff. "Landscape location" refers to hydraulic, geomorphic and/or habitat conditions influencing the acceptability of a given bridge location. "Right bank" and "left bank" refer to the side of the channel when viewing downstream. Findings The study findings and recommendations are summarized in Table 2. Bridge #1 Location: station 101+90 Status: absent Park priority: high (replacement a priority) Landscape location: acceptable Trail connections: intact Recommendations Replace with a longer span (34 feet minimum) and a broad arch form for improved conveyance capacity. a Station numbers are referenced to the project topographic survey, and indicate distance in feet upstream from a control point. The stations are 100 feet apart; for example, station 98 is 100 feet upstream from station 97. The number 98+75, for example, means 75 feet upstream from station 98. C Ashland Creek Environmental Report Appendix Four Page 7 Bridge #2 (Atkinson Bridge) Location: station 105+70 Status: present Park priority: high Landscape location: acceptable Trail connections: intact Recommendations Repair the apparently minor flood impact damage to the upstream face of the span. Bridge #3 Location: station 111+10 Status: present Park priority: high (access to maintenance shed) Landscape location: acceptable Trail connections: intact Recommendations Repair minor bank erosion in this vicinity on an as-needed basis. The gunite/"rockcrete" abutments are undercut and will be subject to rapid failure in future flood events. Bridge #4 Location: station 113+00 Status: absent Park priority: low (no need to replace) Landscape location: poor Trail connections: intact Recommendations Do not replace. Location is unsatisfactory from a number of standpoints. The very large instream boulder at this location interferes with flow conveyance and will tend to rack up debris and enhance bank erosion. However, this boulder provides good habitat (scour pool below) and may be impossible to move in any case without dynamiting. There are existing bridges 400 feet upstream and 550 feet downstream (Atkinson Bridge) of this bridge location, providing adequate access across the creek. Allow the grouted/gunite-covered banks here to naturally deteriorate or remove and replace with boulders. The prominent gap at the former abutment location on the left bank should be repaired with a rock treatment and blocked off to prevent public access to banks and channel for reasons of both safety and erosion control. 0 0 MN - Ashland Creek Environmental Report-, Appendix Four Page 8 d O CD co CO o rn O X n d~ N N~ M M O Y a O M ~ d O O ` U O ~ ns C ~ ~ O C N t•, ~ 3 U_ U d t W w+ C r'.cc a; 5 . ~p > U u o c. t0 0 CL S- cm N .O ,.W- V W C_ O t L a d O C U y C a> E O U Y O C i U as ca = ee d ° Cc a O p > 0 iIm m w y 'D 'O om co as a> a1 = r~ a) C C CD U O v O O O O C a7 _ C d C C vi i U aQ N M E E a i ~r i i ~ > fy9 O = C t6 U fts U a c L-: o p > O cn ° L) CD No z U O_ OTC Z E o Q o p a0i w o Z = Z r_ CL 0 C y O 0 o y F~ U m ° as rr W cm m 'C c CD M 'C U O a o .y t0 m o w a J m 4) W o d ! 'a o Y c a a' a) d o L N_ U cn z d J O V U U U Q V ca m m as W f+ n. Z C C O C Z O d U a Z m d m cn Q a a a O p U d o m (1) U a U U Z Q cVa cc W W p W W w z 2 2 2 r~.r O W N W ~O W W Q Zp O O J Ur p a ~ z o N z o 0 0 0 O o) r- r- o d + + + + r- L r- c+) ~ o o r- cn r- N W W ~ O m Z d 3 STREAM CHANNEL REHABILITATION Introduction These observations and recommendations are organized by stream section, or "reach," starting at the Hersey Street bridge and working upstream. Within each reach, we have documented existing conditions, and have recommended near-term improvements, and long-term improvements. Objectives are provided for all recommended improvements. The station numbers are approximate and can be determined from the figures included at the end of this report. "Left" and "right" bank refer to the bank when looking downstream. Some of these recommendations will need to be evaluated for effect on flood hydraulics before they are implemented. Some recommendations might not be acceptable to City or Park staff due to physical or operational constraints. Findings and Recommendations Findings and recommendations are summarized in Table 3. Hersey St. to Main Street Reach; Stations 75+50 to 94+00 Existing Conditions: The stream channel above Hersey St. bridge is primarily a riffle between culverts, where small pools are generally formed by the drop. Substrate is gravel/cobble/small boulder with moderate to heavy embeddedness (sand). The lower part of the reach is largely confined but the banks are natural appearing; the upper section of the reach is tightly confined and the banks have been modified from their natural condition with slurry concrete. Near-term improvements: Remove all floatable woody debris, flood debris, and cultural debris from channel and channel margins. Objective: Improve channel appearance and minimize downstream flood risk from debris accumulation. O 0 Ashland Creek Environmental Report Appendix Four Page 10 Station 81+80: Remove old flashboard dam piers ( "Dragon's Teeth"). Objective: Minimize the opportunity for debris accumulation in the channel. Station 84+30: Remove old building foundation on left bank. Objective: Improve channel appearance and flow conveyance.' Station 84+00: Protect large cottonwood from eventual undermining and toppling with selected boulder placement. Objective: Save large streamside tree. Long-term improvements: Culvert floors throughout this reach are all smooth and present fish passage barriers at both high and low streamflows. Structures should be modified with baffles or other roughness devices to facilitate fish passage. Objective: Improve fish passage conditions. Station 78+50 left bank: Rebuild bank adjacent to recycling center. Bank is presently composed of dumped asphalt. Construct new bank at lower angle (2H: IV) and protect with rock toe. Replant with native woody riparian vegetation. (Note: This recommendation would conflict with the proposed development of a skateboard park at this location.) Objective: Enhance visual appeal; approve fish habitat. Station 80+40: Remove or modify artificial grade control structure. One option would be to remove the structure and install a single channel spanning boulder weir. Another possible option would be to construct a porous "ramp" out of large boulders leading up to the existing structure. ' As a policy, buildings or other structures should not be allowed in the stream channel. O Ashland Creek Environmental Report Appendix Four Page 11 Objective: Facilitate fish passage; provide grade control; provide visual interest and fish-holding habitat in this riffle-dominated reach (see Figure 1) Station 81+00: Reduce the drop downstream of the Van Ness bridge by adding large boulders to the pool tail. Objective: Provide visual interest and increase pool depth for fish habitat; improve fish passage. Water Street/Bluebird Park Reach; Stations 81+00 to 94+00 Other than some riparian zone habitat improvement potential, this reach offers only limited habitat enhancement opportunities. The reach of Ashland Creek through Bluebird Park to the Main Street bridge is essentially a concrete-lined ditch with only very limited habitat value under existing conditions. Calle Reach (Guanajuato Way); Stations 94+00 to 100+00 Existing Conditions: The stream channel above the boulder knickpoint up to the plunge pool/backwater pool just below the original Winburn Way box culvert concrete apron is primarily riffle; substrate is gravel/cobble/small boulder heavily embedded with sand. Left bank is a poured concrete wall upstream from Main Street to the footbridge at Station 96+50 (with low bouldery bench below this in places); upstream of bridge becomes steep boulder flood deposit (95 feet long, +8 feet high, mainly large boulder/cobble); the gunite/boulder treatment continues upstream to the culvert. Right bank is gunite/boulder treatment upstream from Main Street to footbridge (interrupted by a short section of poured concrete wall). Gunite continues a short distance upstream of the footbridge and becomes a poured concrete wall supporting the overhanging deck (which has now been removed). The concrete wall transitions upstream to an eroding bouldery/sandy bank with two established maple trees rooted in the steep bank. Finally, a short section of stacked concrete slabs extends upstream to the culvert. Near-term Improvements: Remove diseased trees (mainly alders with bark abraded by flood impact) identified by Park staff. Cut as low as possible to the ground surface and leave roots to decay in place. Objective: Minimize downstream flood risk from debris accumulation; preserve bank stability. Remove racked up woody debris on boulder knickpoint just upstream of the Main Street Bridge. Objective: Minimize downstream flood risk from debris accumulation. O Ashland Creek Environmental Report J Appendix Four Page 12 Remove in channel debris (asphalt and concrete pieces) which has been marked with a pink "X." Objective: Improve channel appearance. Long-term Improvements: Station 94+25 Convert the existing loose, boulder-controlled knickpoint to a large boulder "'porous ramp" or staggered weir. A ramp structure would be sufficiently "impermeable" to maintain a shallow backwater pool (in this instance) as currently exists but would be sufficiently "porous" (i.e., have sufficient gaps) to allow fish passage under ordinary flow conditions. (Such a structure would probably need to be grouted unless very large stone was used; further hydraulic analysis would be required to determine if grouting is required for stability reasons). A staggered weir structure would consist of several channel-spanning boulder weirs, one below the other, which would maintain the backwater pool but provide sufficiently low drops to allow fish passage under ordinary flow conditions'. Grouting requirements are as noted above. Either type of structure should span the entire channel and should be secured to the existing banks where feasible. The structure(s) should have an upstream-arch configuration in plan view and should have a shallow dip toward the channel centerline to focus the flow away from the banks. Objective: Facilitate fish passage; provide grade control; provide visual interest and fish-holding habitat in this riffle-dominated reach (the structure would be highly visible from Main Street Bridge). (See Figure 3) Station 94+50 A few large boulders could be placed in the shallow backwater pool upstream of the boulder knickpoint for visual interest. The boulders should be placed with a low enough profile so that they do not unduly accumulate floating debris. Very large boulders should be placed and deeply embedded into the substrate so that no artificial anchoring is required. Objective: Add visual interest; provide additional fish habitat diversity. 4 Note: all placed instream boulders should be "granitic" in composition, blocky and subrounded to rounded in shape, i.e. they should appear to be native river rock. Quarry rock should not be used in visible locations as it would appear unnatural. s The weirs constructed under the new Winburn Way bridge are good examples of this type of facility. a a ~ Ashland Creek Environmental Report Appendix Four Page 13 Station 94+00 to Winburn Way crossing Locally repair failed sections of the rock/cement (gunite or shotcrete) bank facing as needed. In lieu of the gunite/boulder treatment, we recommend a treatment consisting of carefully placed river boulders which are grouted in a manner minimizing the visibility of the cement grout (i.e., the grout should be removed from visible rock faces so the boulders look like a natural rock bank). This treatment could include tree wells on the upper part of the bank. Objective: Improve bank stability and visual appearance. (See Figure 4) Station 95+50 Build a channel-spanning boulder weir with plunge pool by placing a number of +24-inch boulders. Objective: To break up the long, visually uninteresting riffle here; provide additional fish habitat diversity. Station 95+75 Build a channel-spanning boulder weir with plunge pool by placing a number of +24-inch boulders. Add a few large boulders to create a short deflector on the left bank to protect several streamside trees (if these are to be retained). Objective: To break up the long, visually uninteresting riffle; provide additional fish habitat diversity. Station 96+75 to 97+00 Remove the flood-damaged overhanging deck.6 Objective: Improve flood conveyance and public safety. Station 97+00 to 98+00 Left bank boulder flood deposit. This consists of sand, gravel, cobble mixed with large boulders. This represents a very droughty, coarse-grained deposit with a south aspect (little revegetation potential). The area is unattractive and highly visible from the Calle. Proposed Treatment. The rehabilitation of this section of streambank is dependent on hydraulic/flood passage considerations and on the geotechnical engineering design that will be developed for the hillslope failure above this bank. Ideally, this bank could be designed to provide usable space along the creek, and to provide fish habitat elements. One concept is to create a low terrace adjacent to the creek, using grouted boulders for low retaining walls. 6 The overhanging deck has recently been removed. 0 0 Ashland Creek Environmental Report Appendix Four Page 14 Objective: Attractively stabilize the streambank. Add visual interest; provide additional fish habitat diversity. Provide more public space on the west side of the creek across from the Calle. (See Figure 5) The ±15 ft. high failure slope above the boulder deposit. Scarps above existing trees suggest that this slide is likely to be re-mobilized this winter. Total failure is highly probable within the same time frame. The slope is highly visible from the Calle. The area at top of the failure is grassed public open space. Proposed Treatment. A retaining wall is necessary to buttress the slope. We think this should be an attractive feature (because of visibility from the Calle) that can incorporate steps up to the upper open space area near Granite Street. Stone or log structures, or a textured concrete structure, are obvious options. For aesthetic reasons, we would recommend against treatments using gabions, concrete blocks, sheet piling or similarly intrusive, unattractive options. Vicinity of Winburn Way crossing Existing culverted crossing to be replaced. In-channel and bankside designs have been incorporated in the final bridge design and alignment. Lower Lithia Park Reach (Winburn Way to Butler Bandshell); Station 100+00 to 114+00 Existing Conditions The stream through this reach is channelized and moderately to highly confined and flowing close to bedrock. Substrate is predominantly boulder/cobble (the streambed is probably armored) with abundant superficial sand deposits. The lower part of this reach is almost exclusively riffle. Pools (mostly backwater type, some small plunge pools and lateral scour pools) are more abundant in the upper part of this reach. However, all pools are veneered with deep sand deposits and generally lack overhead cover, minimizing their habitat value. Banks consist mainly of boulder/cobble/sand with minimal groundcover and shrub growth. Trees are relatively abundant on both banks (good canopy cover) and many are rooted in the vicinity of the summertime water surface elevation. Most of the existing bankside trees appear stable and should remain so under expected flow conditions (no severely leaning, partially-uprooted trees were evident). Trees consist mainly of white alder, maple, and ash. Many of the trees (especially alders) have been abraded by the flood and this has lead to insect damage; these fatally-diseased trees should be removed by Park staff as soon as possible. Banks are in an eroded condition in a number of places; these areas are susceptible to further scour by high flows. The failure mode is direct hydraulic action leading to grain-by-grain removal. 0 Ashland Creek Environmental Report Appendix Four Page 15 Near-term Improvements: Remove diseased trees identified by Park staff. Cut as low as possible to ground surface and leave the roots to decay in place. Objective: Minimize downstream flood risk from debris accumulation. Remove in-channel flood debris and large floatable woody debris (previously marked with a pink "V). Objective: Improve channel appearance and minimize downstream flood risk from debris accumulation. Long-term Improvements: Station 100+00 to 101+80 (Right Bank) Restoration/enhancement recommendations will depend on final engineering of the approach to the Winburn Way crossing. Final placement of the park flood wall and bridge wingwall will dictate channel and bank improvements. Station 100+00 to 101+00 (Left Bank) Restoration/enhancement recommendations will depend on final engineering of approach to Winburn Way crossing. Final placement of bridge wingwall and road retaining wall will dictate channel and bank improvements. Station 101+90 Instream habitat improvement. Construct an at-grade boulder weir (Figure 3) with plunge pool in the pinched channel segment just upstream of the bridge. Objective: Improve channel appearance and fish habitat complexity. The weir would be visible from the bridge and will add amenity value. Station 102+30 to 103+30 (Left Bank) Proposed Treatment. Remove two diseased alders at downstream end of this area. Minimal width (11-18 feet) between the waterside edge of the sidewalk and the low-flow channel margin. Construct a retaining wall or bank revetment through this reach. We recommend a grouted stone wall or high- angle grouted boulder bank, as previously described. The wall or bank could be wavy in plan view, forming lower bank "pockets" where trees could be planted (or preserved) and similar pockets along the sidewalk for vegetation. Remove the existing angular riprap at the upstream end of this section O Ashland Creek Environmental Report Appendix Four Page 16 and replace with previously described treatment. The alignment of the newly-constructed upstream boulder revetment on the right bank (see below) forces flow into this bank. This underscores the need for a particularly robust treatment here. Objective: Protect the streambank from further erosion; protect the sidewalk. (See Figure 6) Station 102+90 to 103+60 (Right Bank) Park staff constructed an ungrouted boulder revetment on the right bank. This appears likely to remain stable under expected future flows. The bank above has been planted. We suggest placement of a few additional large boulders at the upstream end of this treatment to prevent any flanking of the structure. Station 103.70 to 104+00 Proposed Treatment. An existing backwater pool provides good fish habitat (many fish observed in this area during the field assessment); extensive undercut roots of large maple on left bank. Enhance the pool by building up a porous weir at the head of the riffle. Place boulders adjacent to undercut roots to enhance local scour. Place a few boulders on right bank to deflect flows toward undercut roots. Station 104+20 (Left Bank) A large boulder has slid down the bank. Reposition into the eroded alcove along the sidewalk. Add additional rock to fill obvious large gaps. Station 105+00 to 105+70 (Right Bank) Children's Wading Area. This is a good feature but the flat, wide channel bottom creates very shallow flow during the summertime. This is not conducive to the passage of fish or other aquatic organisms, or to temperature amelioration. However, benefits probably outweigh any disadvantages. The concrete slab channel floor is also beginning to deteriorate in places. Eventual repair could include alteration of the streambed to allow a low flow channel (although this would reduce the wading opportunities). Station 105+80 to 107+80 (Right Bank) Children's Playaround. The playground closely encroaches on the creek, creating an unstable bank situation. Average distance between the low-flow channel margin and the playground fence is approximately 12 feet (bank height here is approximately 8 feet). We recommend that the fence and playground be relocated about 10 feet landward of the existing location, if this is feasible in relation 0 Ashland Creek Environmental Report ~ Appendix Four Page 17 to playground design and safety standards. The new playground edge could be "wavy" for visual interest. The bank can then be reconstructed with large boulders placed in a manner leaving "planting pockets" where trees can be planted. Station 108+00 (Right Bank) Break up the pieces of cemented rock on the bank here and place and restore boulders to the channel, taking care not to cause bank erosion as a result of boulder placement. Station 109+50 (Concrete dam/diversion structure) Significant fish barrier. Drop is 4.5 feet from top of structure to lower water surface. Average plunge pool depth is 2.5 feet. Maintain structure for grade control (stream is adjusted to this). Install an engineered fish ladder on right bank for fish passage. Station 110+25 (Concrete dam/diversion structure) Significant fish barrier. Drop is 2.5 feet from top of structure to water surface. Average plunge pool depth is 2.8 feet. Maintain structure for grade control (stream adjusted to this). Install an engineered fish ladder on right bank. Consider hardening the right bank in this vicinity, which is heavily trampled. We carefully considered options for these two dams/diversion structures. We advise against removing the structures because they control the stream grade, and removal could precipitate grade changes up- and downstream. Simple fish ladders are recommended rather than other options such as boulder step-pools or ramps because of cost and hydraulic impacts. Fish ladder design could incorporate rock facing or other treatments for visual quality. The sediment accumulations on the upstream sides of these structures should be removed periodically to maintain a minimum water depth for fish passage. Station 110+50 (Left Bank) There is currently considerable informal access from the parking area into the long backwater pool here. Close off portions of this area with barrier logs and create hardened access point(s). Station 112+25 (Right Bank) Remove the large concrete block (abutment or bridge foundation remnant) from channel. Replace the block (if feasible) with 4-5 large stream boulders to maintain a favorable scour pool downstream of the block. 0 0 Ashland Creek Environmental Report Appendix Four Page 18 Station 113+00 Repair the banks with boulders where the bridge abutments are to be removed. Instream Habitat Improvement. This area is high visible from the gazebo. If the gunite-covered bank is to be rebuilt, consider adding a ramp log extending into the pool, keying this into the right bank. Replant the upper bank. 4 PROJECT STAFF Fishman Environmental Services Paul A. Fishman, M.S., C.E.P. Senior Ecologist Steven R. Johnson, B.S. Aquatic/Fisheries Ecologist Watershed Applications, Ltd. Todd Moses, M.A. Geomorphologist Scott Morris, Ph.D. Fluvial Geomorphologist O Ashland Creek Environmental Report Appendix Four Page 19 Table 3: RECOMMENDED STREAM CHANNEL IMPROVEMENTS (Shaded cells indicate improvements that have recently been completed.) STREAM REACH STATION RECOMMENDED OBJECTIVE (approximate) IMPROVEMENT (see note at end) Hersey to Main Streets Reach 75+50 to 94+00 entire reach remove floatable wood, F, A demolition and cultural debris (N) all culverts install baffles or other FP treatments on culvert bottoms 81+80 remove concrete "dragon F teeth" (l) 84+00 left bank protect large cottonwood E, FH, F tree (N) 84+30 remove cement foundation F, A, FH from stream channel (N) 78+50 left bank remove asphalt, rebuild and FH, A plant bank (L) 80+40 remove or modify grade FP, FH, G control structure (L) 81+00 improve pool below Van FP, FH, A Ness culvert (L) Calle Reach 94+00 to 100+00 entire reach remove diseased trees (N) F, B R I. 94+00 remove w °W (V x; F entire reach remove flood dehj"q A 96+75 remove 'ti;.`.:. ' ry F 94+25 create "staggered weir" (L) FP, G, A, FH 94+50 place large boulders (L) A, FH entire reach repair/replace failed gunite A, B (L) 195+50;95+75 create boulder weirs (L) 7 A, FH 0 o~ Ashland Creek Environmental Report Appendix Four Page 20 Table 3 (continued) STREAM REACH STATION RECOMMENDED OBJECTIVE (approximate) IMPROVEMENT (see note at end) 97+00 to create boulder bank and A, B, FH, R 98+00 terrace (L) Lower Lithia Park Reach 100+00 to 114+00 entire reach remove diseased trees (N) F, B entire reach F, A 'I~~saody 100+00 to 101+80 design stream bank rehab to B, A key in to Winburn Way work (L) 101+90 construct boulder weir (L) A, FH 102+30 to 103+30 construct bank revetment B left bank (L) 102+90 to 103+60 place boulders at upstream B right bank end of new revetment (L) 103+70 to 104+00 enhance fish habitat with FH porous weir and boulders (L) 104+20 left bank reposition large boulder (L) B 105+00 to 105+70 possible creation of low FP right bank flow channel (L) 105+80 to 107+80 move fence and playground B, A, F right bank about 10 ft inland (L) 108+00 right bank break-up cemented rock B clusters (L) 109+50 Concrete dam: construct FP engineered fish ladder on right bank (L) 110+25 Concrete dam: construct FP engineered fish ladder on right bank (L) O Ashland Creek Environmental Report Appendix Four Page 21 Table 3 (continued) STREAM REACH STATION RECOMMENDED OBJECTIVE (approximate) IMPROVEMENT (see note at end) 110+50 left bank Restrict access from parking B lot; create hardened access points (L) 112+25 right bank Remove large concrete A, FH block from channel; replace with boulders to maintain plunge pool (L) 113+00 Repair bank with boulders B, A after bridge abutment removal (L) Key to table: N = Near-term project; L = Long-term project F = minimize flood risk; B = protect stream bank; A = improve aesthetics G = provide grade control; FP = improve fish passage; FH = improve fish habitat R = improve access and recreation use; EC = erosion control right or left bank as viewed looking downstream 0 0 Ashland Creek Environmental Report Appendix Four Page 22 5~ S ~oNb o V SERY lS w v W o LLJ O' 0 Lw y~ ST. O LLJ _ ct LN ~S -cis Q ct W Li w U O LLJ 5 w > m w ~ Q l u~=w Z \ (nwL)w mwcnC),~- - JS ♦ y Cn = o 41 d a m~ O v Z m ~O<y 0 e7 cr-- . O F - cn U y~ ~ cl:~ y 8 Q02 \ vJ cr 06 Q ~z b c._ 0o u~nOo v N N = e E Z w N L m O O ~ L3. C G. v~G~ a 1S ~oooo yM e U cl~ O ~nb8 >>i w Q Q o O Q z Q~~ J `'~'yj m O o ~ ~ ~ J b0~ O c n O~Q by S -{~>>b > C) w O ST. ti~ D < a w ~ b~ Sl c~n L) FO S41 Goo L Q) LID Lo GLENVIEW DR. bbd S c 3 /Yj L ST. z ~ v - :7 w 1S ~2~d3d mi o w ~ is U w imms V, ca w 2 Q w > 2 O LY z w cn c o m = O_ J w L. Z Q a O U < ~ c Ln U F- b M01 7R ° U) v c c`c w a o w m 3 V) w r- cn c UJ J n L) O Q W (n Lj1 0 U W p iQ Q Q o J > ~C V~ a. ' d o ~ 3 c o ® W o o . n F y 0 q D J K ~ C C a° 11 E :r 0 UD ~o ~oo 00 •N v c <r ' X ^ CZ 'El z • =Q-'to ~d "r, ov ~ U • .N CIO Cr O m ~ ~/_r1y~Or. U H.•Lw~ V L.I : :::~'.'}}}:::'ti't u V ~ 106 0 to -v ~ w co v ~ v ca ~ ~ rn G VD (:)N a i 0+ cz vi ~m t: n - z C7 r O D s.. v r/I v m). IL ® III U ~I C FLOW Riffle Riffle % • • • Plunge Pool , ; . ' Boulder Weir Riffle FLOW • • Cascade with Micro-Pools Riffle Boulder Ramp LEGEND Conaultantsor ecology and Ashland Creek natural reforuce mmragematt o Fishm® Environwental 5ccvicee DRAWN: T. Moses 434 NWSLtAvcnuc.Sum304 Flood Restoration Project J Portland Oregon 97209-3600 (503)223-0333 APPROVED: P. Fishman 7 DATE: October 1997 Watershed Applications BOULDER WEIR SCALE: No sale & BOULDER RAMP TREATMENTS 4.11 NW Seth Ave. Suite 305 PoNana, Oregon 97209 Figure 4 3 Project 4 97037-2 Large Shrub or Small Tree in Planting Pocket Walkway Grouted Boulders , Creek • LEGEND mmmgemeat nam-hl2rouice owce Ashland Creek ° haft -1 334 NW ESua rr Aveaue~ servs- 304 DRAWN: _I Moses Portland. Oregon 97209.3600 Flood Restoration Project (503)224-0333 APPROVED: P. Fishman DATE: October 1997 f j1~ltershed Applications GROUTED STONE BANK TREA'T'MENT SCALE: No scale 434 ma sodh Ave. Suds 305 PorOantl, Oregon 97209 Figure # •4 Project # 97037-2 i v 1 Lawn Creek Low Stone Retaining Wall Grouted Boulders . . LEGEND °~"artfs "eCO`°gy cmd nerr<>~ >u°,Ke ~gmu Ashland Creek Ashland Creek Fishman Ern iroomerrml services DRAWN: T. Moses "i WSixtbAvenue •Suire304 Flood Restoration Project ~ Portland. Oregon 97209-3600 (503)224-0333 APPROVED: P. Fishman DATE: October 1997 =f!m= 11%~tershed Applications LOW BOULDER BANK TREATMENT SCALE: No scale 434 NW Si nn Ave. Suns 305 PoNand. Oregon 97209 Figure # 5 Project 4 97037-2 4i f ~r New Planting on Street Level Bench `f r Q ~t Preserved Q Existing Streamside c Trees ~ LS Retaining "rye Wai I Edge of • Water r' j• New Planting on Street Level Bench • LEGEND uluuta "-`°gyan° Ashland Creek wnvd nsoiace mmwgnnenr ` Fishmm Envievomental Servixs DRAWN: T Moses " 434N4O hAo a ue- S itO3~ Flood Restoration Project PonW (503)224-0333 APPROVED: P. Fishman DATE: October 1997 `ietershed Applications POSSIBLE RETAINING WALL SCALE: No scale CONFIGURATION ALONG WINBURN WAY 434 NW Sam Ave. SuMe 305 Portland. Oregon 97209 Figure # 6 Project # 97037-2 APPENDIX FIVE to Ashland Creek Flood Restoration Project Final Report November 3, 1997 Ashland Creek Early Action Items April 28, 1997 Submitted to: City of Ashland Ashland, Oregon Submitted by: Otak, Inc. 17355 SW Boones Ferry Road Lake Oswego, OR 97035 (503) 635-3618 M e m o r a n d u m To: Ashland Park Commission From Lawrence Magura and the Otak Project Team 17355 SW Boones Ferry Rd. Copies: Greg Scoles, City of Ashland, and any concerned Lake Oswego, OR F97035 erry Phone (503) 635-3618 citizens Fax (503) 635-5395 Date: April 28, 1997 Subject: Early Action /Flood Risk Reduction Measures - Otak Project No. L7844 Introduction The Otak team has been placed under contract by the City of Ashland to make recommendations for actions that are prudent to reduce the risk of flood during the upcoming year. It was initially estimated that some of the larger project improvements, such as improvements to the Winburn Way crossing may not be completed within this up- coming building season. As such, there is a continuing degree of flood risk to the areas impacted by last January's flood event until stream channel improvements can be completed. In the short term, however, some improvements that will be part of a larger, comprehensive effort can be constructed which will significantly reduce the risk of flooding in the Park front lawn and Plaza areas. We were requested to evaluate the stream conditions and report our initial recommendations to you. Providing more immediate recommendations will allow you and the community an opportunity to consider possible improvements that may be constructed this summer and be in place before the start of the next rainy season. Although most of these recommendations are expected to be completed near the end of May, recommendations relating to lower Lithia Park were delivered to you this last week. These recommendations are described more fully within this memorandum. One of the objectives that was identified to us was the need to make recommendations for visual and aesthetic enhancements to the lawn area of Lithia Park (Lower Lithia Park) directly adjacent to the Plaza by May 1, 1997. Visual and aesthetic enhancements would need to be constructed in such a way that they would not have to be reconstructed once our final recommendations are available by the end of May. To make these recommendations, we evaluated proposed flood risk reduction improvements together with various flood risk reduction scenarios. P: \ PROJECT \ 7800 \ 7844 \ FLDREPOR \APPENDE \ EARLYACT.MO1 Early Action/Flood Risk Reduction Measures Otak L7844 April 28, 1997 Page 2 Ken Mickelsen has advised the team that any proposed solutions should be evaluated using the following criteria: ■ Enhance and improve the riparian corridor along Ashland Creek; ■ Should include a flood protection "line of defense"; for fighting future floods; ■ The lawn area should be functional for multiple park use; ■ Any proposal must blend with the existing aesthetics and historical characteristics of Lithia Park. Although significant citizen involvement is proposed for the total flood restoration project, the Consultants understood that some of the early action items may have limited opportunity for involvement because of the more immediate nature of the recommendations. The Otak Team developed a concentrated effort to analyze several alternatives for interim action items related to lower Lithia Park. Out of the various scenarios, three prominent concepts emerged and were considered in more detail. Each concept was designed to redirect overbank flows that might occur in lower Lithia Park back to the existing channel above Winburn Way for storm events similar in intensity to the storm event that caused the New Years flood. These concepts included: 1. Raise the grade of the lawn to a higher elevation, so that the low spot will not exist to convey future flood events towards the Plaza area. 2. Construction of a flood protection berm along the outside fringe of the lawn area near the creek. 3. Construct an aesthetically-designed, rock-faced, structurally-sound flood wall similar in appearance to the existing rock walls in the park. Each of the alternatives has merit, but the third alternative provided the best solution under the criteria mentioned above. The rock wall concept not only provides a measure of flood protection, it also meets several other park objectives. The wall is designed to create a demarcation boundary between an active use lawn area and what can become an enhanced riparian zone. The wall serves to separate two distinct areas of the Park. The lower Lithia Park lawn has historically been used for active recreational use including picnicking, lounging, walking, gatherings, July 4th celebration and other uses. It is also the primary feature for pedestrian connections between the Park and the Plaza. The use of the wall would not require significant alterations to the existing elevation of the lawn area. The wall could provide a measure of flood protection and preserve the historical characteristics and use of the lawn area. P: \ PROJECT \ 7 800 \ 7844 \ FLDREPOR \APPENDE \EARLYACT..MO 1 Early Action/Flood Risk Reduction Measures Otak L7844 April 28, 1997 Page 3 Secondly, the wall helps to clearly establish a wider riparian zone between the lawn and the creek. This particular area sustained significant erosion damage during the recent flood. The area between the wall and the creek can be developed into an enhanced riparian zone. The wall would be aesthetically pleasing and would match the scale and texture of existing walls within Lithia Park. Lithia Park has numerous locations where rock walls are used to enhance the physical and visual characteristics of the Park. The wall proposed by the Consultants would continue this theme in a manner that is aesthetically pleasing and consistent with the overall architectural characteristics of the Park. It is our vision that, in years to come, park visitors will see the wall as an integrated aesthetic feature, not knowing its design also provides a measure of flood risk reduction for the Ashland community. Our recommendation for the flood wall was based on the extensive professional experience of the Otak project team members with similar structures on other projects. Based on our review of photographs of the lower park area taken during the flood event (provided by the City), it appears that a wall between two and three feet in height, with an adequate foundation, would have been sufficient to deflect the New Year's Day flood waters back towards the creek, and would probably have been able to keep flood water out of the Plaza. An important benefit of a flood wall, especially in areas of relatively shallow flooding, is that they create a line of defense that can be used effectively for sand bagging during future major flood events, thereby giving a fairly modest wall the capability of being temporarily raised to protect against more extreme events. Once a detailed hydrologic and hydraulic evaluation of Ashland Creek has been completed, a specific level of flood protection can be assigned to such a structure. The level of protection provided by the wall itself is one important attribute. Another is created when the wall is evaluated in conjunction with other planned improvements, such as the removal and replacement of the major channel constriction that is caused by the existing Winburn Way Culvert. If the culvert is upgraded to a higher flow capacity, then the level of flood protection provided by the low stone wall will also increase incrementally: The wall, without culvert replacement, may itself provide something on the order of 25-year level of flood protection to the Plaza, but the wall along with a new crossing at Winburn Way may work out to more than 100-year level of flood protection. Clearly, the wall is a "down payment" on reducing future flood damage in the Plaza area, but that down payment, combined with other measures, such as replacing the Winburn Way culvert and the creation of an enhanced riparian corridor between the wall and the creek, seem to clearly make it a "win-win" proposition. For these reasons, plus the fact that the wall itself doesn't require a high degree of hydraulic or engineering analysis to justify its value led to our recommendation that it be built now. Simply put, it's a good idea that fits well into a holistic long-range plan of flood reduction improvements. P: \PROJECT\ 7800 \7844\ FLDREPOR\APPENDE \ EARLYACT.MO 1 Early Action/Flood Risk Reduction Measures Otak L7844 April 28, 1997 Page 4 Our understanding is that the Park Commission has approved the rock wall concept at their April 21, 1997 meeting, subject to comments or questions that may arise within the next few days. Both Clay Moorhead and Paul Fishman (Principals with firms on the Otak Team) were in Ashland April 22 and 23 to conduct stakeholder interviews, evaluate the response to the Park Commission action and to gather ecological data on Ashland Creek. Both Clay and Paul attended a publicized meeting of the Ashland Watershed Partnership (AWP). Clay Moorhead also attended the Chamber Issues Forum on April 23, 1997 to hear comments related to the Park restoration and flood bond measure. At the AWP meeting, Clay and Paul presented the consultant team's alternatives for lower Lithia Park and explained them to the Park Commission. It was specifically mentioned not only by the consultants, but also by members of the AWP, that the action of the Commission left open the opportunity to present concerns related to the proposed rock wall recommendation. Numerous concerns, questions, and alternatives were raised at the AWP meeting concerning the Otak team's recommendation to build a flood wall in lower Lithia Park. It should be noted that many of the technical questions that were raised at this meeting had previously been asked of the consultant team by Parks and Recreation Department staff during our April 16th meeting with them. At that time, the Otak team thoroughly addressed these similar technical concerns when they were raised by staff, and the meeting concluded with a clear consensus for proceeding with the flood wall. The Otak team has carefully reviewed the questions, comments, and suggestions that were made during the AWP meeting. Since the same basic questions were previously asked and answered during our earlier meeting with Parks and Recreation staff, we did not hear anything new of a substantive nature at the AWP meeting that would require us to revise or change our recommendation to construct the flood wall this year, before the next rainy season starts. It should be noted, however, that at both the meeting with Department staff and the AWP meeting, the consultant team pointed out that refinement of the wall design height would certainly be possible and desirable if the results of the proposed detailed computerized hydraulic model of Ashland Creek were available before construction commenced. We anticipate that, when the City of Ashland authorizes us to proceed with development of the computer model, the results generated will only serve to confirm our recommendation to build the flood wall in the lower lawn area of Lithia Park. AWP Issues, Concerns, Comments 1. What happens if a flood goes around/behind the wall upstream? Paul Fishman and his staff were on site April 23 and looked at the area of the park upstream of the existing wall to which the proposed flood wall would link. One of the park staff showed us that flood water had been about 1-foot high against the existing P:\PROJECT\7800\7844\ FLDREPOR\APPENDE\EARLYACT.MOI Early Action/Flood Risk Reduction Measures Otak L7844 April 28, 1997 Page 5 wall. The park area east of the existing wall (i.e., away from the creek) is higher elevation than the path and the area between the wall and the creek. It appears that flows coming out of the creek in the vicinity of the playground area would follow the existing contours along the path and towards the creek and front lawn area, and would be contained by the proposed wall and the higher ground extending from the wall towards the playground area. The proposed wall could be extended south along the path if needed to insure flood containment, the small area in question could be easily sand bagged during a flood event if the threat of outflanking actually developed. 2. An alternative was proposed instead of the three alternatives we had proposed: change the grade in the front lawn area so the elevation decreases from the sidewalk along the east edge of the park (i.e., along the base of the OSF facilities) towards the creek. The existing front lawn of the park is the low spot of the park, and conveys flood flows into the Plaza area. Reducing the elevation of the front lawn so that it grades towards the creek will make this low spot even lower, thereby exacerbating the problem of flood conveyance into the Plaza area. 3. Can the wall be designed so that panels can be added to the top of the wall, thereby increasing the wall height if needed for a larger flood event? This can be considered; however, added wall height will require wider and deeper wall footings. The goal of Phase 2 of our project, however, will be to provide adequate hydraulic capacity within the Ashland Creek floodway to minimize the occurrence and volume of overbank flows in the park, thereby eliminating the need for greater wall height. As an interim measure, however, the wall can be used as a line of defense for effective sand bagging operations, with added height being provided by sand bags stacked up on the lawn side of the proposed wall. 4. Is there a more "temporary" solution to the front lawn area, such as an earthen berm that could be removed later? This is possible. Any temporary solution would need to be designed to provide the desired flood protection, which might mean rock armoring of an earthen berm and other measures. One of our goals was to recommend a solution that would be compatible with park uses and aesthetics, and would not need to be removed later, causing future disruption to the park lawn. 5. Can the existing configuration of Winburn Way (with the temporarily lowered "swale" profile) handle a flood event similar to the last one without flooding the park and plaza? In other words, is the wall needed at all? P:\PROJECT\7800\1844\FLDREPOR\APPENDE\EARLYACT.MOI Early Action/Flood Risk Reduction Measures Otak L7844 April 28, 1997 Page 6 We can't answer this question until we have the hydraulic model developed. The wall recommendation assumes that the Winburn Way crossing would not convey a similar event without flooding some portion of the park, and is therefore a form of insurance for that event. It is highly unlikely that citizens and City staff would be comfortable with a swale in Winburn Way as a long-term flood control measure. Swales are OK in rural areas, but are generally regarded as incompatible with urban values. 6. The wall design should consider the elevation of the base of the wall in respect to potential scouring from a flood event that would undermine the wall. We agree. 7. There is some concern that the wall is a permanent object that might not work (i.e., provide flood protection). The wall could be removed if that decision was ever made, so it does not necessarily need to be regarded as a permanent addition to the park. Our professional evaluation determined that the wall will provide a measure of flood protection for the park lawn and plaza area. The design complements the existing design and uses of the park. 8. We are "putting the cart before the horse" by designing the wall (or other facilities) before we have collected hydrologic data and built the hydraulic model. The wall is a recommendation that our preliminary evaluation determined will provide the desired measure of flood protection in the event another flood similar to the last event occurs before the Winburn Way crossing and other problems are corrected. Once built, the wall becomes a parameter of the hydraulic model and will be factored into the design of other facility changes in the stream system. The hydraulic improvements that will be proposed for the entire stream study reach (Hersey Street to Butler Bandshell) will be integrated with the wall design to protect the city and park from future flood events larger than the New Year's Eve storm. Using the same analogy used in the comment, we're not really pulling the horse with the cart, we're choosing to ride the horse for awhile before we hitch it to the cart so we can make some progress on our journey. 9. Can't some flood event overwhelm or go around the wall? The recommended design for the wall is based on providing flood protection for an event similar to the January 1997 event. There is certainly the possibility of a larger flood event out there somewhere in the future. Our design process for the entire project (i.e., the Hersey Street to upper Lithia Park study reach) will consider a variety of possible storm events, and decisions will need to be made concerning the size storm event that P: \ PROJECT \ 7900 \ 7844 \ FLDREPOR\APPENDE \ EARLYACT.1101 Early Action/Flood Risk Reduction Measures Otak L7844 April 28, 1997 Page 7 flood protection facilities will be designed to handle. The resulting design will incorporate other measures that will, together with the wall, provide the design event protection for storms larger than the New Year's Eve event. Storm protection measures in urban areas are generally designed for a 100-year or more extreme flood event. This assumes that an event larger than the 100-year event will overwhelm the flood protection facilities, and other measures will need to be implemented to protect life and property. Alternative Plan of Action The Otak Team continues to strongly support our original recommendation to build a low flood wall as an immediate improvement to provide a measure of flood protection for lower Lithia Park and the Plaza area this year. The results of the proposed modeling work can be available in a couple of months. As an alternative plan of action, the following sequence of actions is suggested: 1. Approve the rock wall concept as an early action item and proceed with regrading and planting of the lower lawn area in a way that will leave a construction zone for construction of the wall at a later date. This construction zone would be graded and seeded after construction of the wall is completed. 2. We believe that the City's risk of flooding has diminished considerably between now and the middle of November 1997. If construction of the wall is determined to be a prudent improvement, then it should be in place prior to the end of November 1997. Allowing a minimum of three to four months for construction of the wall would mean that a final decision on this matter should occur no later than July 31, 1997. Based on these assumptions, we need to be very clear that deferring a decision on whether to build the wall beyond July 31, 1997 is in fact a decision as well. The effect of deferring this issue beyond July 31, 1997 will likely mean that the rock wall will not be built in time to provide a measure of protection prior to the start of the next flood season. The Otak team would like to suggest an alternative to the immediate construction of the flood wall for consideration by the Commission: Delay construction of the flood wall until after the proposed computer modeling work is completed, if the City authorizes us to begin the modeling work within the next 30 days or so. The work itself can be completed within about two months after receiving authorization to proceed. If the Commission chooses to accept this alternative, this decision would have the following impacts: (1) the start of wall construction would be delayed by about three months; and (2) the concerns raised at the AWP meeting about building the wall before the modeling results are available would be eliminated. P:\PROJECT\7800\7844\FLDREPOR\APPENDE\EARLYACP.MO1 Early Action/Flood Risk Reduction Measures Otak L7844 April 28, 1997 Page 8 Additional Comment. As mentioned in the beginning of this memorandum, these recommendations are only part of the recommendations for early action items to reduce flood risk in Ashland. Further recommendations are being developed and will be presented later in May. The Otak Team will endeavor to continue to encourage public involvement in the development of our recommendations. Thank you for your consideration. P:\PROJECT\7800\7844\FLDREPOR\APPENDE\EARLYACT.MO1