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Home My WebLink AboutAgenda AGENDA Utilities Committee Regular Meeting 3:30 PM - Monday, February 1, 2016 Council Conference Room, 7th Floor, City Hall – 1055 S. Grady Way 1. LOWER CEDAR RIVER RESTORATION ASSESSMENT - briefing a) Final Report 2. CEDAR RIVER MAINTENANCE DREDGE PROJECT - briefing a) PowerPoint 3. ESTABLISHMENT OF 165 ST. SANITARY SEWER EXTENSION S.A.D. #48 a) Agenda Bill LOWER CEDAR RIVER CHINOOK SALMON HABITAT RESTORATION ASSESSMENT STUDY HABITAT RESTORATION SITE POTENTIAL AND FEASIBILITY ANALYSIS REPORT Prepared for City of Renton Public Works Department Surface Water Utility Prepared by Herrera Environmental Consultants, Inc. AGENDA ITEM #1. a) LOWER CEDAR RIVER CHINOOK SALMON HABITAT RESTORATION ASSESSMENT STUDY HABITAT RESTORATION SITE POTENTIAL AND FEASIBILITY ANALYSIS REPORT Prepared for City of Renton Public Works Department Surface Water Utility 1055 South Grady Way Renton, Washington 98057 Prepared by Herrera Environmental Consultants, Inc. 2200 Sixth Avenue, Suite 1100 Seattle, Washington 98121 Telephone: 206-441-9080 In association with MacLeod Reckord PLLC November 5, 2015 AGENDA ITEM #1. a) i pjj 14-05933-000 lcrra site potential_feasibility analysis.docx ACKNOWLEDGEMENTS Mayor Denis Law Chief Administrative Officer Jay Covington City Councilmembers Randy Corman Marcie Palmer Armondo Pavone Ruth Pérez Don Persson Ed Prince Greg Taylor Stakeholder Participants Jason Wilkinson, WRIA 8 Technical Committee Scott Stolnack, WRIA 8 Technical Committee Kate Akyuz, King County Water and Land Resources Division Gino Lucchetti, King County Water and Land Resources Division Hans Berge, King County Water and Land Resources Division Larry Fisher, Washington Department of Fish and Wildlife Holly Coccoli, Muckleshoot Indian Tribe Fisheries Division Larry Reymann, Renton Parks Commission Mike O’Donin, Renton Parks Commission Al McKenzie, Renton Rowing Center Elizabeth Butler, Washington State Recreation and Conservation Office City Staff Hebe Bernardo, Project Manager, Public Works Department Surface Water Utilities Engineering Ron Straka, Public Works Department Surface Water Utility Engineering Manager Leslie Betlach, Parks Planning and Natural Resources Director Angie Mathias, Senior Planner, Department of Community and Economic Development AGENDA ITEM #1. a) iii pjj 14-05933-000 lcrra site potential_feasibility analysis.docx CONTENTS Purpose and Scope ......................................................................................... 1 WRIA 8 Chinook Salmon Conservation Plan ............................................................. 3 Habitat Restoration and Mitigation Projects Previously Identified and Implemented in the Lower River ....................................................................................... 5 Projects Identified in the WRIA 8 Chinook Salmon Conservation Plan ......................... 5 Previously Constructed Habitat Improvement Sites .............................................. 6 Identification and Evaluation of Potential Restoration Project Sites ............................... 9 Generation and Initial Screening of Potential Restoration Projects ........................... 9 Candidate Restoration Sites Discarded on Basis of Feedback from City Staff and Stakeholders ..................................................................................... 10 Restoration Project Sites Selected for Detailed Assessment ................................... 10 Multi-Objective Evaluation Criteria Used to Compare Sites ................................... 15 Restoration Projects Recommended for Conceptual Design Development ........................ 19 Additional Actions Applicable to the Entire Lower River ............................................ 21 Conclusion .................................................................................................. 23 References ................................................................................................. 25 APPENDICES Appendix A Existing Conditions and Identification of Potential Habitat Restoration Site Opportunities and Constraints Appendix B Concept Designs and Cost Estimates for Highest Ranked Restoration Sites TABLES Table 1. WRIA 8 Plan Site-Specific Protection and Restoration Projects. ........................ 5 Table 2. Candidate Restoration Sites Evaluated and Compared in Detail. ...................... 11 Table 3. Multi-Objective Criteria and Corresponding Scoring System Used to Compare Candidate Restoration Sites. ................................................................ 16 Table 4 Multi-Objective Criteria Scores and Resultant Rankings of Candidate Restoration Sites. ............................................................................. 18 AGENDA ITEM #1. a) iv pjj 14-05933-000 lcrra site potential_feasibility analysis.docx FIGURES Figure 1. Lower Cedar River Restoration Assessment Project Area. ............................... 2 Figure 2. Candidate Restoration Sites and Evaluation Criteria. ................................... 13 AGENDA ITEM #1. a) November 2015 Lower Cedar River Chinook Salmon Habitat Restoration Assessment Habitat Restoration Site Potential and Feasibility Analysis Report 1 PURPOSE AND SCOPE The City of Renton obtained a grant from the Puget Sound Partnership’s Puget Sound Acquisition and Restoration Fund (PSAR) program to study potential Chinook salmon habitat restoration sites in the lower Cedar River and its floodplain to develop conceptual designs for several sites that are deemed the best opportunities. Selection of this study for a grant was recommended by the Lake Washington/Cedar/Sammamish Watershed Resource Inventory Area (WRIA 8) to demonstrate the importance of this work from the WRIA 8 perspective. The grant application was developed in collaboration with the WRIA 8 Technical Committee, which is actively engaged in Chinook salmon recovery planning and related project implementation in the Cedar River watershed. The City contracted with Herrera Environmental Consultants, Inc. (Herrera), in collaboration with MacLeod Reckord, to conduct this study and develop the conceptual designs. This report presents the methods and results of the study. The scope of this project is largely defined by the City’s commitments to the Washington State Recreation and Conservation Office under the grant. The study limits extend from the mouth of the Cedar River at Lake Washington to approximately river mile (RM) 5.2, which coincides with the length of the river within Renton city limits (Figure 1). The habitat restoration opportunities identified in this study are consistent with the objectives outlined in the WRIA 8 Chinook Salmon Conservation Plan (Plan) (WRIA 8 Steering Committee 2005) and ongoing WRIA 8 Chinook salmon recovery scientific understanding. This report documents the following: • A summary of the conservation strategy outlined in the Plan • A summary of habitat restoration projects previously identified for the lower river • A summary of several habitat restoration and mitigation sites that have been constructed to date • A detailed analysis of potential restoration sites and the process used to compare and contrast them to define the best opportunities that can benefit Chinook salmon, while addressing a variety of other feasibility and implementation considerations • Conceptual design information for six sites that ranked highest in the evaluation process A memorandum produced early in the project that characterizes existing conditions in the lower Cedar River and identifies a wide range of Chinook salmon habitat restoration opportunities is contained in Appendix A. The memorandum provides context for the analysis presented in this report. AGENDA ITEM #1. a) !( !( !( !( !( !( !( !( !( !( !( !( !( !( !( !( !( !( !( !( !( !( !( !( !( !( !(!( !( !( !( !( !( !( !( !( !( !( !( !( !( !( !(!( !( !( !( !( !( !( !( !( !( !( !( !(GFGFGFGFGFREACH 1 REACH 2 REACH 3 REACH 4 Lake Washington Cedar River §¨¦405 UV169 UV900 §¨¦405 RM1 RM5 RM4 RM3 RM2 K:\Projects\Y2014\14-05933-000\Project\Reach_Opportunity\project_area.mxd (1/12/2015) 02,7505,5001,375 Feet Legend Reach break GFRiver mile !(1/10th-river mile Cedar River channel Figure 1. Lower Cedar River Restoration Assessment Project Area. AGENDA ITEM #1. a) November 2015 Lower Cedar River Chinook Salmon Habitat Restoration Assessment Habitat Restoration Site Potential and Feasibility Analysis Report 3 WRIA 8 CHINOOK SALMON CONSERVATION PLAN In 2001, 27 local governments in WRIA 8, including the City of Renton, signed an inter-local agreement to jointly fund the development of a conservation plan to protect and restore salmon habitat and support recovery of Chinook populations in the watershed. The resulting science-based Plan, published in 2005, provides recommendations for prioritized actions to protect and restore salmon habitat, and a collaborative approach for implementing those actions over the ensuing 10 years (<http://www.govlink.org/watersheds/8/planning/chinook- conservation-plan.aspx>). Local jurisdictions were identified as key to implementing the Plan because they can have the most impact on salmon spawning and rearing habitat through implementation of stormwater and land use policies, protection and restoration programs, and opportunities for public involvement. The Plan outlines a conservation strategy that relies on a series of ecosystem objectives and guiding principles (WRIA 8 Steering Committee 2005). The WRIA Technical Committee developed a conservation strategy for Chinook salmon habitat protection and restoration that relied on a set of four ecosystem objectives to form the basis for developing and prioritizing habitat management actions: • Maintain, restore, or enhance watershed processes that create habitat characteristics favorable to salmon. • Maintain or enhance habitat required by salmon during all life stages and maintain functional corridors linking these habitats. • Maintain a well-dispersed network of high-quality refuge habitats to serve as centers of population expansion. • Maintain connectivity between high-quality habitats to allow for population expansion into recovered habitat as degraded systems recover. The conservation strategy analysis determined that two Chinook salmon populations in WRIA 8 are at high risk of extinction, the Cedar River and Sammamish populations. The Cedar River population is at highest risk because of steeply declining abundance trends (WRIA 8 Technical Committee 2010). Because habitat degradation is the primary factor driving that decline, areas used by Cedar River Chinook were identified as the highest restoration priority. The conservation strategy divided areas used by salmon populations into three tiers based on watershed conditions and Chinook abundance and use, with Tier 1 subareas having the highest quality habitat and highest fish abundance, and Tier 3 having the most degraded habitat and infrequent Chinook use. Although the extents of the Cedar River in Renton were identified as Tier 1 subareas, much of the available habitat in the lower 5 miles of the river lacks attributes favorable to Chinook salmon, particularly juveniles that need rearing and refuge habitat that is generally unavailable due to developed land uses on both banks of the river and minimal connectivity of the main stem river with its historical floodplain. AGENDA ITEM #1. a) November 2015 Lower Cedar River Chinook Salmon Habitat Restoration Assessment Habitat Restoration Site Potential and Feasibility Analysis Report 5 HABITAT RESTORATION AND MITIGATION PROJECTS PREVIOUSLY IDENTIFIED AND IMPLEMENTED IN THE LOWER RIVER Identification and design of potential Chinook salmon habitat restoration sites in the lower river is informed by sites previously identified for habitat protection and restoration in WRIA 8 planning work, and the status of several previously constructed salmon habitat sites. This section briefly describes this background information. Projects Identified in the WRIA 8 Chinook Salmon Conservation Plan The Plan included a prioritized list of specific protection and restoration projects in the lower Cedar River within and near the City of Renton. Table 1 lists these projects. The river reaches noted in Table 1 are similar to those shown in Figure 1. As of the time this report was produced, a project that protects existing forested areas along the river from development (project C210) and a project that protects existing good quality habitat features in Reaches 3 and 4 (project C213) have been implemented. Currently the City of Renton manages 251 acres of open space and 538 acres of park land along the Cedar River. In addition, in a three-way partnership between the City of Renton, King Conservation District, and Forterra, invasive and non-native knotweed along the Cedar River riparian corridor is being eradicated and replaced with native plant species (project C209). Table 1. WRIA 8 Plan Site-Specific Protection and Restoration Projects. Reach (see Figure 1) WRIA 8 Project No. Description 1 C201 Explore opportunities to improve habitat in Reach 1 where there are extensive areas of industrial land use C202 Re-vegetate Reach 1 with overhanging vegetation where possible C203 Revegetate riparian areas where possible C204 Explore redevelopment options C205 Protect and maintain existing riparian vegetation 2, 3 C206 Improve riparian habitat in area of industrial use C207 Improve riparian habitat in area of multi-family residential use C208 Maplewood neighborhood flood buyouts and floodplain restoration C209 Riparian restoration in parkland C210 Protect existing forested, riparian habitat in City of Renton’s parkland C211 Restore side-channel on right bank 3, 4 C212 Riparian restoration and conifer underplanting in forested riparian areas, particularly in Ron Regis park near slide area C213 Protect existing riparian habitat and LWD 4 C214 Protect habitat in Reach 4 and explore ways to reduce flooding and erosion in Ron Regis Park such as adding LWD and setback levee AGENDA ITEM #1. a) November 2015 Lower Cedar River Chinook Salmon Habitat Restoration Assessment 6 Habitat Restoration Site Potential and Feasibility Analysis Report Previously Constructed Habitat Improvement Sites Several habitat improvement projects have been constructed in the Cedar River within Renton city limits, primarily as mitigation for maintenance dredging that occurs in the lower mile of the river for flood protection purposes. Most of these projects were not specifically designed to restore or enhance Chinook habitat, but they collectively provide ancillary benefits to Chinook habitat functions and are thus summarized here to provide context for the habitat restoration analysis described in this report. • Sockeye salmon spawning and rearing channels: o In 1998, the Groundwater Side Channel was constructed in the left bank (facing downstream) floodplain on the north edge of Maplewood Golf Course from RM 4.5 to 4.6. o In 2001, the Elliot Spawning Side Channel was constructed in the left bank floodplain from approximately RM 4.55 to 4.8 near the Groundwater Side Channel (and connecting to that channel near the confluence with the river). The project was originally constructed to provide fish-spawning and side-channel habitat. In 2006 and 2009, the berm at the upstream end of the side channel was overtopped by flood flows that caused large debris piles to accumulate at three areas in the channel and erosion of the channel banks, and resulted in silt deposition that reduced spawning habitat functions. The side channel was repaired in 2012 to once again improve and provide off-channel aquatic spawning and rearing areas. Sand and debris were removed from approximately 1,200 linear feet (LF) of the channel. Logs with root wads were installed, gravel substrate was placed, eroding side slopes were repaired, and vegetation that had been eroded during the floods was replanted (Renton 2015). o The groundwater side channel constructed in 1998 was destroyed by a landslide triggered by the Nisqually earthquake in 2001. The slide inundated the side channel, obliterating its ability to function as off-channel habitat. In partnership with the US Army Corps of Engineers, the City of Renton re-established a sockeye salmon spawning and rearing side channel (called the Cedar River Spawning Channel) along the Cedar River between RM 3.4 and RM 3.6 in 2009. The project consisted of the following elements:  Construction of an intake structure at the upstream end of the channel to convey controlled amounts of flow from the Cedar River  Construction of an open channel outlet approximately 1,200 feet downstream from the intake structure to allow flows to re-enter the Cedar River and allow fish to migrate in and out of the channel  Excavation of approximately 6,000 cubic yards of gravel, sand, and silt  Shaping an existing drainage course for approximately 1,000 feet to create the replacement channel  Addition of 600 to 900 cubic yards of gravel to create spawning habitat AGENDA ITEM #1. a) November 2015 Lower Cedar River Chinook Salmon Habitat Restoration Assessment Habitat Restoration Site Potential and Feasibility Analysis Report 7  Installation of native vegetation at two locations along the channel and between the Cedar River and the new channel  Construction of a 12-foot-wide gravel maintenance path adjacent to the west side of the channel, installation of an access gate to deter illegal vehicle access, and installation of educational signs to inform the public • In 1999, the Maplewood Large Woody Debris Levee Project was constructed between RM 4.75 and RM 4.85. This project involved placing large woody debris and building a bioengineered revetment along an existing rock revetment on the left bank of the river at Maplewood Golf Course. • In 1999 to 2000, riparian vegetation was planted at two locations along the lower mile of the river. Approximately 4,850 LF of vegetation was planted on the right bank of the river between South Boeing Bridge to the river mouth (RM 0.75 to RM 0), and approximately 3,800 LF of vegetation was planted from Logan Avenue North to the aircraft hangars on the left bank (RM 1.1 to RM 0.4). In the ensuing 10 years, much of this vegetation died on the left bank. • The Royal Hill Replacement Spawning Channel was constructed in 2010 at approximately RM 3.4. This project replaced the groundwater spawning channel that was overtaken by the Cedar River as a result of the landslide in 2001. The replacement spawning channel is located downstream of the original groundwater spawning channel, just upstream of Maplewood Golf Course (and across the river from Southeast 10th Place and Shelton Avenue Southeast). The project construction included installation of approximately 900 LF of channel with gravel substrate, a culvert inlet structure, anchored large woody debris, a maintenance access road, gate, and riparian habitat plantings. • The bridge over the Cedar River with instream piles at Riverview Park (RM 2.73) was demolished in July of 2014 and was replaced in fall 2015 with a single span bridge with a grated deck that allows more sunlight to reach the water’s surface. The project includes invasive species removal and riparian plantings approximately 650 feet upstream and 200 feet downstream of the bridge on the left bank of the river and roughly 30 feet upstream and downstream of the bridge on the right bank. While these projects collectively have improved habitat for a variety of salmonid species, including Chinook, they were not explicitly designed to provide habitat for Chinook. The two side channels near Maplewood Golf Course and riparian plantings downstream of there are beneficial for juvenile Chinook rearing and refuge. The Cedar River Spawning Channel at RM 3.3 to RM 3.6 is purposefully managed for sockeye spawning, which entails higher velocity flows than are optimal for Chinook rearing and refuge. The side channels near the golf course are particularly important because they represent the only off-channel habitat connected to the river at a range of flow conditions that juvenile Chinook can routinely make use of within Renton city limits. AGENDA ITEM #1. a) November 2015 Lower Cedar River Chinook Salmon Habitat Restoration Assessment Habitat Restoration Site Potential and Feasibility Analysis Report 9 IDENTIFICATION AND EVALUATION OF POTENTIAL RESTORATION PROJECT SITES This section presents a discussion of Chinook salmon habitat restoration sites that were identified and evaluated in the current project, resulting in recommendations for sites to carry forward into conceptual design development. The WRIA 8 Chinook Conservation Plan recommendations for the Cedar River that are pertinent to this assessment include: • Emphasize restoration and long-term maintenance of publicly-owned riparian areas • Restore riparian vegetation wherever possible • Construct a bank restoration demonstration project in a publicly accessible area that includes elements doable by an average property owner • Explore redevelopment and restoration options to effect buffer and floodplain improvements Generation and Initial Screening of Potential Restoration Projects Potential restoration sites were initially identified based upon existing data sources such as published documents and studies, previously adopted plans, aerial photos, high-resolution lidar elevation data, maps, survey data, photos from a floating survey of bank revetment conditions in the lower river conducted by Herrera for the concurrent Cedar River Corridor Plan project being led by King County, and geographic information system (GIS) data. An interdisciplinary team of Herrera staff then performed field reconnaissance along the river banks and in floodplain areas to determine locations that could allow for cost-effective habitat restoration. A project meeting was convened in late January 2015 with City staff from the Public Works Department and Parks Planning and Natural Resources Division and other Cedar River stakeholders to discuss existing Chinook salmon habitat, land use conditions along the river, and potential habitat restoration sites. Stakeholders who attended this meeting included representatives of the Renton Parks Commission, Muckleshoot Indian Tribe Fisheries Division, WRIA 8 Technical Committee, King County Water and Land Resources Division, Renton Rowing Center, and Washington State Recreation and Conservation Office. The discussion in that meeting about potential restoration sites yielded some additional sites and design approaches to consider, and elimination of several sites from further consideration. Through the initial site identification process and with input from the stakeholder group, 28 candidate sites were identified for further screening. These are listed in the memorandum in Appendix A. AGENDA ITEM #1. a) November 2015 Lower Cedar River Chinook Salmon Habitat Restoration Assessment 10 Habitat Restoration Site Potential and Feasibility Analysis Report Candidate Restoration Sites Discarded on Basis of Feedback from City Staff and Stakeholders Based upon input provided by the stakeholder group, the following sites/concepts were eliminated from consideration before more detailed analysis was performed: • Floating riparian islands – deemed risky from a long-term anchoring/stability perspective, and because they could potentially create habitat for fish that are Chinook predators. • Tributary stream reconnection at existing wetland area in Riverview Park – deemed unacceptable because it would result in elimination of the existing wetland, which is perched above river level, and its functional habitat for amphibians and terrestrial animals. Existing wetland conditions were field verified by Herrera in spring 2015. • Madsen Creek confluence area restoration – deemed too complicated for this project to undertake, as there are numerous factors in flux that may affect the future outlet of Madsen Creek to the river. Furthermore, this confluence area may not be an effective location to attempt Chinook habitat restoration. • Molasses Creek alluvial fan area restoration – deemed infeasible to create a large enough restoration site in this location to be worth pursuing given constraints to modifying the existing condition. • Boulder clusters in the main channel – deemed a hazard for recreational floaters and too difficult to incorporate wood or overhanging vegetation that would create desired habitat for Chinook. Restoration Project Sites Selected for Detailed Assessment After culling the site list of candidate sites as described above, project team members from the City, Herrera, and MacLeod Reckord performed additional field reconnaissance to refine the conceptual restoration approach at numerous sites, and to better define the geographic limits of the sites. This reconnaissance resulted in eliminating some additional sites from further consideration due to identification of constraints, and in some cases realization that the habitat that could be created would not be a cost-effective use of available funds compared to other more viable sites under consideration. A total of 14 restoration sites were analyzed in detail, using multi-objective criteria developed in coordination with City staff and with input from stakeholders (specifically representatives of WRIA 8, the Renton Parks Commission, and King County Water and Land Resources Division). Table 2 lists the sites that were analyzed in detail. Figure 2 shows the locations of these sites. The criteria are described in detail in the next section of this report. AGENDA ITEM #1. a) November 2015 Lower Cedar River Chinook Salmon Habitat Restoration Assessment Habitat Restoration Site Potential and Feasibility Analysis Report 11 Table 2. Candidate Restoration Sites Evaluated and Compared in Detail. Site ID River Mile Description 1 1.1 Create shallow sandy alcove, add LWD, and plant riparian vegetation on right bank just upstream of Logan Avenue North. 2 1.1 to 1.45 Relocate Cedar River Trail along the right bank between the Senior Activity Center at RM 1.1 and Bronson Way South at RM 1.45, and grade the river bank where the existing trail lies to provide shallow water habitat with LWD and overhanging native riparian vegetation. This project would have a lesser footprint than described for site no. 3. 3 1.1 to 1.45 Relocate Cedar River Trail along the right bank between the Senior Activity Center at RM 1.1 and Bronson Way South at RM 1.45, and grade the river bank where the existing trail lies to provide shallow water habitat with LWD and overhanging native riparian vegetation. This project would have a greater footprint than described for site no. 2, extending the bank modification up to street level above the existing retaining wall and blending with redevelopment in the adjacent neighborhood per the City Center Community Plan. 4 1.1 to 1.6 Remove gabions, concrete wall and other armoring on left bank between I-405 and Logan Avenue North (including at Jones Park, where a bank modification design was prepared in 2008 but not completed), remove invasive vegetation, and install native plantings on bank with bioengineered bank stabilization methods as applicable. 5 1.5 to 1.6 Remove soft surface trail and invasive vegetation on right bank (area currently fenced off), and create shallow habitat bench with LWD and native plantings at the downstream end where there is room to excavate without removing mature trees. 6 1.7 to 1.8 Create shallow sandy alcove, add LWD, and plant riparian vegetation on right bank upstream of existing “amphitheater” that is heavily used for beach access (note: an alternative may be viable to shift the location of this alcove upstream to property corner, but doing so could induce removal of some mature trees). 7 1.8 to 2.15 Enhance right bank in conjunction with Tri-Park Master Plan redevelopment to flatten right bank to provide shallow edge habitat at range of flows, remove invasive vegetation and armoring, and/or install LWD and bioengineered native plantings. 8 2.15 to 2.4 Remove invasive vegetation on right bank adjacent to Riviera Apartments and plant native riparian vegetation. 9 1.85 to 1.9 Excavate alcove/backwater slough on left bank selectively to retain mature trees and fit in with Tri-Park Master Plan for site improvements, install LWD and native plantings in disturbed area. 10 3.2 Connect inlet and excavate outlet to create flow-through side channel conditions in left bank floodplain. 11 3.3 to 3.6 Selectively plant native shading vegetation along both banks of existing Cedar River Spawning Channel. 12 4.3 to 4.5 Add LWD on channel margins in ways that do not create recreational safety hazard. 13 4.7 Plant willows on both banks and place LWD at the downstream end of the Elliot groundwater channel. 14 4.4 to 4.5 Create side channel on left bank at edge of golf course. RM – river mile. LWD – large woody debris. AGENDA ITEM #1. a) AGENDA ITEM #1. a) November 2015 Lower Cedar River Chinook Salmon Habitat Restoration Assessment Habitat Restoration Site Potential and Feasibility Analysis Report 15 Multi-Objective Evaluation Criteria Used to Compare Sites For any potential Chinook salmon habitat restoration site to be carried forward to implementation along the Cedar River in Renton it must be viable from a variety of perspectives. This is particularly true because most of the land bordering both sides of the river is in public ownership with existing uses that could be affected by a restoration project. Therefore, a thorough evaluation process was used to compare and contrast the 14 candidate restoration sites with each other, based upon multi-objective criteria. City staff who were involved in the project from the outset, from the Public Works Department and Parks Planning and Natural Resources Division, provided input on restoration site evaluation criteria of importance from the City’s perspectives. Those criteria encompass a broad range of considerations from park users’ experience to maintenance requirements to compatibility with other planning efforts the City has undertaken. In collaboration with the core team of City staff, Herrera developed criteria specific to habitat restoration objectives that link to WRIA 8 restoration objectives for Chinook salmon. A draft list of evaluation criteria was then shared with the same group of stakeholders who provided input in January 2015, to get their feedback and to confirm completeness of the criteria. The outcome was the list of criteria presented in Table 3, with score values assigned as shown in the table. Anticipated habitat restoration value was weighted the highest among all other criteria because for any candidate restoration site to be considered worthy of implementation over other sites it has to have strong potential for improving Chinook salmon habitat. Each of the 14 sites was qualitatively assessed using best professional judgment to determine which of the habitat creation/restoration criteria are applicable to the site, to assign score values for those habitat criteria that apply, and to assign appropriate score values for all of the other criteria. Then the sum of the scores for the habitat creation criteria was multiplied based on the site’s relative size: small (multiplier of 1), medium (multiplier of 2), or large (multiplier of 3). This multiplier was not applied to the other criteria. All of the criteria point scores that were assessed for a particular site were then summed to yield a total score. Higher scores indicate greater overall habitat restoration benefit along with other ancillary benefits and/or lesser complications anticipated in implementing the project. Sites with higher scores were therefore considered more worthy of advancing to conceptual design as described in the following section. The sum total score for each of the sites is presented in Table 4 with a corresponding ranking compared to the other sites. The total scoring for sites 5, 10, and 13 produced a three-way tie. A tiebreaker was applied to those sites such that a higher score for the habitat creation criteria warranted a higher ranking among the three, to select a sixth site to carry forward into conceptual design. AGENDA ITEM #1. a) November 2015 Lower Cedar River Chinook Salmon Habitat Restoration Assessment 16 Habitat Restoration Site Potential and Feasibility Analysis Report Table 3. Multi-Objective Criteria and Corresponding Scoring System Used to Compare Candidate Restoration Sites. Criteria Points Description Habitat Creation 3 Would provide off-channel rearing habitat and high flow refuge for juvenile Chinook. 2 Would provide main stem edge habitat for juvenile Chinook that is currently not available in the site location. 2 Would add functional large woody debris (LWD) for improved habitat complexity. 2 Would provide tree shade (canopy cover) to reduce water temperatures in larger area of the river used by juvenile Chinook. 2 Would provide food sources and channel edge cover (overhanging vegetation) to reduce localized water temperatures in areas used by juvenile Chinook. 1 Would reduce predation of juvenile Chinook salmon via eliminating predatory fish habitat, or reducing potential for predation by birds. Multiply sum of total habitat creation points by factor of 1, 2, or 3 based on relative site size Assign the highest value applicable to the site for each of the following criteria: Flood and Erosion Risk Reduction 0 Would have minimal effect on flooding or bank erosion conditions in the lower river. 2 Would reduce flooding and/or bank erosion locally at the restoration site. 3 Would reduce flooding on multiple properties along a length of the river and/or eliminate a significant bank erosion risk. Park Effects -2 Would reduce park area, or otherwise reduce park uses. 0 Would not change park area or use. 3 Would enhance park area or park uses. Trail, Golf Course, and On-River Recreational Use Effects -2 Would complicate or hinder recreational use. 0 No change to recreational uses. 3 Would increase recreational use opportunity, enhance recreational use experience, or improve recreational safety. Constructability -1 Complex construction in the water and/or difficult access for equipment, or potentially risky from a cultural resources or hazardous materials perspective. 1 Moderate constructability issues that should not add a lot of cost or time for project implementation. 3 No or minimal constructability issues. Permitting Complexity -1 Would require full range of local, state and federal permits, and likely to require compensatory mitigation for environmental impacts of construction. 1 Would require full range of local, state, and federal permits, but no mitigation. 3 Would qualify for streamlined permitting process. Funding Potential 0 Not easily fundable with existing grant resources. 2 Fundable by existing City programs. 3 Likely fundable under existing grant programs. Land Rights 0 Site is on private land with no City regulatory control or existing easement. 2 City has regulatory control or an existing easement on the private land, or could otherwise obtain that control without a lot of difficulty. 3 Site is owned by the City or other public entity. AGENDA ITEM #1. a) November 2015 Lower Cedar River Chinook Salmon Habitat Restoration Assessment Habitat Restoration Site Potential and Feasibility Analysis Report 17 Table 3 (continued). Multi-Objective Criteria and Corresponding Scoring System Used to Compare Candidate Restoration Sites. Criteria Points Description Site Maintenance and Self- sustaining Performance Expectations -1 Extensive maintenance could be required for years following construction to control invasive vegetation or unwanted sediment deposition, or maintenance access difficult. 1 Occasional, simple maintenance attention could be required over the long term to accomplish habitat objectives and maintenance access could readily be provided. 3 Negligible maintenance expected for site to accomplish intended habitat objectives. Potential to Bundle with Another Site for Amplified Ecological Lift or Other Benefits 0 No logical site nearby to couple with. 2 Could be bundled with a nearby site such that aquatic habitat could improve to greater extent or implementation would be easier for one or both sites. 3 Clear potential for boosted cumulative outcomes or implementation benefits. Assign as many of the following points to the site as are applicable: Additional Considerations 1 Opportunity to bundle habitat restoration with another planned project/action at the site, thus enhancing potential to implement the restoration component. 1 Habitat restoration at the site would be consistent with adopted plans. -1 Habitat restoration site construction could damage existing functional habitat. 2 Habitat restoration at the site would offer a distinct public education opportunity due to highly visited location. AGENDA ITEM #1. a) November 2015 Lower Cedar River Chinook Salmon Habitat Restoration Assessment 18 Habitat Restoration Site Potential and Feasibility Analysis Report Table 4 Multi-Objective Criteria Scores and Resultant Rankings of Candidate Restoration Sites. Site ID Habitat Creation Flood and Erosion Risk Reduction Park Effects Trail, Golf Course, and On-River Recreational Constructability Permitting Complexity Funding Potential Land Rights Site Maintenance and Self-Sustaining Potential to Bundle with Another Site for Other Considerations Total Score Rank 1 6 0 0 0 3 3 3 3 3 3 2 26 4 2 12 0 0 -2 3 1 3 3 3 3 2 28 3 3 21 0 0 3 -1 -1 3 0 1 3 4 33 2 4 21 0 0 0 1 3 3 3 1 0 2 34 1 5 6 0 0 -2 3 3 3 3 3 2 2 23 6 6 6 0 -2 0 1 3 3 3 3 0 3 20 10 7 14 2 -2 3 -1 1 3 0 1 2 3 26 4 8 6 0 0 0 -1 3 3 0 1 2 0 16 14 9 8 0 -2 3 -1 1 3 3 3 0 2 20 10 10 16 0 -2 0 1 1 3 3 1 0 0 23 6a 11 8 0 0 0 3 3 0 3 3 0 1 21 8 12 4 0 0 0 1 1 3 3 3 2 0 17 12 13 7 0 0 0 3 3 3 3 3 0 1 23 6 14 6 0 0 -2 1 1 3 3 1 2 2 17 12 a Site No. 10 wins tiebreaker based on highest habitat creation score compared to sites 5 and 13. AGENDA ITEM #1. a) November 2015 Lower Cedar River Chinook Salmon Habitat Restoration Assessment Habitat Restoration Site Potential and Feasibility Analysis Report 19 RESTORATION PROJECTS RECOMMENDED FOR CONCEPTUAL DESIGN DEVELOPMENT The City’s scope of work under the grant that funded this study required conceptual design development for up to six restoration sites. The six highest ranked restoration projects/sites (Table 4) were thus carried into conceptual design, adhering to the conceptual restoration approach initially identified for each of those sites (Table 2). As conceptual design development work progressed and more was learned about how best to tailor the restoration approach at a specific site, each concept was adapted to maximize Chinook salmon habitat restoration potential within known constraints. Constraints included such things as prevailing water levels at a range of flow rates in the river, property boundaries, topographic features, and existing trees that can ideally be retained. Existing site bathymetry and bank topography information was derived from a combination of cross- sections from an existing conditions hydraulic model used by the City for analysis of the pending dredging project in the lower 1+ mile of the river (NHC 2014), lidar data for upland areas near the river, and GIS data furnished by the City. Draft conceptual design sketches (plan views and cross-sections) were provided to the core team of City staff involved in the study for review and comment, then the refined conceptual design sketches were presented at a public meeting on June 11, 2015. The sketches and companion descriptive narratives were subsequently shared with the stakeholder group for review and comment. The input provided by these various reviewers is reflected in the final conceptual design results presented in Appendix B, including a brief narrative, construction cost estimate, and graphic plan view and cross-section view for each of sites 1, 2, 3, 4, 7, and 10. This design information aligns with conceptual design guidelines set forth by the Washington State Recreation and Conservation Office (2015). AGENDA ITEM #1. a) November 2015 Lower Cedar River Chinook Salmon Habitat Restoration Assessment Habitat Restoration Site Potential and Feasibility Analysis Report 21 ADDITIONAL ACTIONS AND RESTORATION PROJECT IMPLEMENTATION CONSIDERATIONS APPLICABLE TO THE ENTIRE LOWER RIVER The Muckleshoot Indian Tribe Fisheries Division is highly concerned that artificial light from development bordering the river is adversely affecting Chinook salmon behavior and increasing predation. Reducing artificial light penetration to the river is desirable, and will be analyzed on a case by case basis in the design phase as a component of restoration projects presented in Appendix B as well as in other areas not associated with those project sites, or as a separate habitat improvement project. Implementation of artificial light reduction measures would be dependent on available funding, land rights, permit requirements, and other factors. Another important and widely applicable concern is invasive vegetation growth along the lower river that degrades riparian habitat quality and reduces native food sources for salmon. Removing invasive vegetation and replacing it with native trees and shrubs to improve riparian cover and shade on park lands and other City-owned lands on both banks of the river, particularly downstream of I-405, would be beneficial for fish, wildlife, and pollinators, and can be done in ways that do not hinder views and access to the river by people. Warm temperatures in the river can be a significant barrier to salmon migration in some years. If vegetation is planted on a levee or adjacent to a floodwall in the lower river that is managed so that it remains eligible for federal funding for repair or other modifications (as is the case with existing levee and floodwall facilities downstream of approximately Williams Avenue North), the plantings will be subject to requirements and guidance set forth by the US Army Corps of Engineers (USACE). Specifically, the guidelines presented in Engineering Technical Letter (ETL) 1110-2-583 (USACE 2014), or superseding guidance published by the USACE, will apply. AGENDA ITEM #1. a) November 2015 Lower Cedar River Chinook Salmon Habitat Restoration Assessment Habitat Restoration Site Potential and Feasibility Analysis Report 23 CONCLUSION The information presented in this report satisfies in full the City’s obligations under the grant agreement that funded the project work. The conceptual design information presented in Appendix B is readily useful for the WRIA 8 Technical Committee to use in crafting its future work plans, and also for King County, the City of Renton, and other partners to use in ongoing work to develop and implement the Cedar River Corridor Plan. Input received from various City departments during the course of completing this study, along with input from several stakeholders, has resulted in widespread support for the restoration projects that have been conceptually designed. This creates momentum to make those projects a reality in the years ahead. Before design can be completed at any of the restoration sites presented in Appendix B, some additional data gathering, analysis, and/or public outreach will be needed as described in the narrative accompanying each site’s conceptual design information. The candidate restoration sites described in this report that were not carried into conceptual design development should not be forgotten. All of the potential restoration sites evaluated in detail have some potential benefits for Chinook salmon. There is value in advancing restoration planning and design work at any of sites 5, 6, 8, 9, and 11 through 14 that was beyond what the current project could accomplish. AGENDA ITEM #1. a) November 2015 Lower Cedar River Chinook Salmon Habitat Restoration Assessment Habitat Restoration Site Potential and Feasibility Analysis Report 25 REFERENCES GeoEngineers. 2014. Mitigation Plan – Final Report. Cedar River Maintenance Dredging Project. Prepared for the US Army Corps of Engineers, Seattle District, on behalf of the City of Renton, Renton, Washington. 85 pp. NHC. 2014. HEC-RAS hydraulic model files for the Cedar River, RM 0 to RM 2.1. Northwest Hydraulic Consultants, Seattle, Washington. Renton. 2015. SWP-27-3605 Elliot Spawning Channel Repair Project. City of Renton, Washington. Accessed at: <http://rentonwa.gov/business/default.aspx?id=32160>. USACE. 2014. Guidelines for Landscape Planting and Vegetation Management at Levees, Floodwalls, Embankment Dams and Appurtenant Structures. Technical Letter No. ETL 1110-2-583. US Army Corps of Engineers, Washington, DC. April 30, 2014. WRIA 8 Steering Committee. 2005. Final WRIA 8 Chinook Salmon Conservation Plan. Accessed at: <http://www.govlink.org/watersheds/8/planning/chinook-conservation-plan.aspx>. WRIA 8 Technical Committee. 2010. Technical Memo 2006-01. Finalized September 1, 2010. Washington State Recreation and Conservation Office. 2015. Manual 18: Salmon Recovery Grants. Washington State Recreation and Conservation Office, Salmon Recovery Funding Board, Olympia, Washington. January 2015. AGENDA ITEM #1. a) APPENDIX A Existing Conditions and Identification of Potential Habitat Restoration Site Opportunities and Constraints AGENDA ITEM #1. a) APPENDIX A: LOWER CEDAR RIVER CHINOOK SALMON HABITAT RESTORATION ASSESSMENT – EXISTING CONDITIONS AND IDENTIFICATION OF POTENTIAL SITE OPPORTUNITIES AND CONSTRAINTS Prepared for City of Renton Public Works Department 1055 South Grady Way Renton, Washington 98057 Prepared by Herrera Environmental Consultants, Inc. 2200 Sixth Avenue, Suite 1100 Seattle, Washington 98121 Telephone: 206-441-9080 In association with MacLeod Reckord PLLC April 1, 2015 AGENDA ITEM #1. a) i pjj 14-05933-000 appendix a_lower cedar river restoration assessment.docx CONTENTS Introduction ................................................................................................. 1 Existing and Historical Conditions ........................................................................ 1 Geography, Land Use, and Vegetation in the Floodplain ........................................ 3 Hydrology ............................................................................................... 5 Hydraulics .............................................................................................. 7 River Channel Characteristics ....................................................................... 8 Channel Migration ..................................................................................... 8 Large Wood Presence ................................................................................. 9 Aquatic and Riparian Habitat ........................................................................ 9 Historical Contamination ............................................................................ 10 Summary of Existing Conditions Implications for Habitat Restoration ....................... 12 Restoration Opportunities and Constraints ............................................................ 12 Reach 1 (RM 0.0 – RM 1.6): Lake Washington Reach .................................................. 13 Reach 2 (RM 1.6 – RM 3.3): Lower Trail Reach ........................................................ 15 Reach 3 (RM 3.3 – RM 4.6): Maplewood Reach ........................................................ 17 Reach 4 (RM 4.6 – 5.2): Landslide Reach ............................................................... 18 Next Steps .................................................................................................. 19 Solicit Stakeholder Input on Candidate Restoration Actions ................................... 19 Define Restoration Site Layouts and Impacted Land Uses ...................................... 19 Analyze Performance and Feasibility of Candidate Restoration Sites ........................ 19 Prepare a Restoration Site Potential and Feasibility Analysis Report ........................ 19 Develop Concept Designs ........................................................................... 19 Public Outreach ...................................................................................... 19 References ................................................................................................. 20 ATTACHMENTS Attachment A. Potential Restoration Site Maps Attachment B. Regulatory Database Output of Documented and Potential Contaminant Release Sites AGENDA ITEM #1. a) ii pjj 14-05933-000 appendix a_lower cedar river restoration assessment.docx TABLES Table 1. Cedar River Peak Discharges. ............................................................. 5 Table 2. Candidate Restoration Actions – Reach 1. .............................................. 13 Table 3. Candidate Restoration Actions – Reach 2. .............................................. 15 Table 4. Candidate Restoration Actions – Reach 3. .............................................. 17 Table 5. Candidate Restoration Actions – Reach 4. .............................................. 18 FIGURES Figure 1. Lower Cedar River Restoration Assessment Project Area. ............................ 2 Figure A-1. Reach 1–Restoration Opportunity Along the Cedar River, Renton, Washington. ................................................................................ A-1 Figure A-2. Reach 2–Restoration Opportunity Along the Cedar River, Renton, Washington. ................................................................................ A-2 Figure A-3. Reach 3–Restoration Opportunity Along the Cedar River, Renton, Washington. ................................................................................ A-3 Figure A-4. Reach 1–Restoration Opportunity Along the Cedar River, Renton, Washington. ................................................................................ A-4 Figure B-1. EDR DataMap Area Study. ................................................................ B-1 AGENDA ITEM #1. a) April 2015 Lower Cedar River Chinook Salmon Habitat Restoration Assessment— Existing Conditions and Identification of Potential Site Opportunities and Constraints 1 Introduction Herrera Environmental Consultants (Herrera), in collaboration with MacLeod Reckord, is helping the City of Renton to conduct an assessment of Chinook salmon habitat restoration potential and specific restoration site alternatives in the Cedar River and its floodplain within the City’s jurisdiction. The scope of this project is largely defined by the City’s commitments to the Washington State Recreation and Conservation Office, the State granting agency. The project has been funded through the Puget Sound Acquisition and Restoration Fund (PSAR). This memorandum characterizes existing conditions and identifies Chinook salmon habitat restoration opportunities in the lower Cedar River from river mile (RM) 0.0 to RM 5.2 (Figure 1). A subsequent report will present detailed analysis of restoration opportunities and outline site-specific, feasible restoration actions to benefit habitat for Chinook salmon and other aquatic species. The information presented in this report is the result of collecting and synthesizing existing documents and studies, previously adopted plans, aerial photos, high-resolution lidar (light detection and ranging, which is a method of aerial survey that enables reasonably accurate definition of the ground surface) elevation data, maps, survey data, GIS data, and other relevant information to provide an overview of historical conditions and characterize existing conditions within the assessment area. In addition, an interdisciplinary team of Herrera staff performed field reconnaissance to define the locations and character of existing Chinook salmon habitat, and locations where existing land use, flow conditions, topography, and other factors could allow for cost-effective habitat restoration. Based upon the findings of the field work and review of available information, Herrera prepared this report with input from MacLeod Reckord with respect to park and trail considerations. The remainder of this memorandum summarizes existing and historical conditions, describes restoration site opportunities and constraints, defines specific candidate restoration site areas, and outlines next steps in the project to evaluate candidate restoration sites. Existing and Historical Conditions The lower Cedar River lies within the Puget Lowland in King County, Washington. Existing conditions in the lower river are largely the result of extensive human modification of the natural river system. It is likely that the area between Lake Washington and the Interstate 405 (I-405) crossing was a very dynamic part of the river prior to development, but it has been channelized and diverted from its natural courses. There is geologic evidence that the river frequently alternated outlets, sometimes draining into Lake Washington and sometimes into the Duwamish River via the Black River. In 1912 the lower Cedar River was set in its current alignment when a canal was dug from near the present-day I-405 crossing to Lake Washington. The lake was lowered by about nine feet in 1916, thus switching the ultimate outlet of the Cedar River from the Duwamish Estuary (via the Black River and Duwamish River) to the Hiram Chittenden Locks on the Lake Washington Ship Canal in Seattle. Upstream AGENDA ITEM #1. a) !( !( !( !( !( !( !( !( !( !( !( !( !( !( !( !( !( !( !( !( !( !( !( !( !( !( !(!( !( !( !( !( !( !( !( !( !( !( !( !( !( !( !(!( !( !( !( !( !( !( !( !( !( !( !( !(GFGFGFGFGFREACH 1 REACH 2 REACH 3 REACH 4 Lake Washington Cedar River §¨¦405 UV169 UV900 §¨¦405 RM1 RM5 RM4 RM3 RM2 K:\Projects\Y2014\14-05933-000\Project\Reach_Opportunity\project_area.mxd (1/12/2015) 02,7505,5001,375 Feet Legend Reach break GFRiver mile !(1/10th-river mile Cedar River channel Figure 1. Lower Cedar River Restoration Assessment Project Area. AGENDA ITEM #1. a) April 2015 Lower Cedar River Chinook Salmon Habitat Restoration Assessment— Existing Conditions and Identification of Potential Site Opportunities and Constraints 3 of I-405 the river corridor is defined by steep valley walls throughout much of its length, including the areas between RM 1.6 and RM 5.2 in the assessment area. Development in and near the floodplain upstream of I-405 has been primarily for recreational facilities and residential land uses, with development density generally increasing in the downstream direction. Compared to other major rivers in western Washington, agriculture and industry has played a relatively small role in floodplain development along the Cedar River, with the exception of the portion of the river downstream of RM 2.5. Heavy industrial and commercial development associated with Boeing, PACCAR, and the Renton Municipal Airport is present along both sides of the river downstream of RM 1.1. There is also a significant commercial development presence on the existing and historical floodplains within this same area. Geography, Land Use, and Vegetation in the Floodplain Downstream of I-405 Existing land cover in the Cedar River floodplain downstream of I-405 (from RM 1.6 to the mouth at Lake Washington) is primarily associated with urban development. Though the banks are completely artificial/constructed in this segment, revegetation efforts have made a positive impact on the quality of the riparian area and now the banks are lined with woody (sometimes non-native) vegetation in many locations. The riparian corridor is extremely thin, however, often only a single row of trees, bordered by structures or pavement. Predevelopment land cover adjacent to the river was likely a mix of deciduous woody vegetation, scrub/shrub wetlands and emergent wetlands. The vegetation types in any given location likely alternated between open water and various stages of early successional forest as the outlet of the river migrated between the Black River and Lake Washington. Open space and parklands within the study area range from undeveloped, vacant land to highly developed parks and trails that abut and cross the river. The river banks are more highly disturbed by park and trail development downstream of I-405 than they are upstream of I-405. Facilities include: • Cedar River Trail Park – extending from Lake Washington to Liberty Park and covering approximately 17 acres along the right (north) side of the river channel, including a paved regional trail approximately 1.5 miles in length, a non-motorized boat launch, boathouse, parking, restrooms, and children’s play area. Segments of the trail are periodically inundated and impassable at moderate flood stages. There are ramps at several street crossings that make the connection between the (lower) riverfront trail and (upper) street system and bridge crossings. • Renton Senior Activity Center – located at RM 1.1 on the right bank, approximately 3 acres in size, including community gardens and regional trail access. • Pedestrian (aka Jones Logan) Park – located at RM 1.1 on the left bank, is an open lawn park with a small viewpoint on the river. • Jones Park – located at RM 1.3 on the left bank, with approximately 350 feet of river frontage and comprising approximately 1 acre, including regional trail and water AGENDA ITEM #1. a) April 2015 Lower Cedar River Chinook Salmon Habitat Restoration Assessment— 4 Existing Conditions and Identification of Potential Site Opportunities and Constraints access, picnic facilities, play equipment, open lawn, a viewpoint, and restrooms. The water access and riverside sitting area is periodically inundated by the river. • Liberty Park – located at RM 1.5 on the right bank, with approximately 650 feet of river frontage and comprising approximately 12 acres, including regional trail access, ball fields with grandstands, tennis courts, shelters and restrooms, parking, a skate park, and a children’s play area. Upstream of I-405 Upstream of I-405, the left bank (south side of the river, facing downstream) has recovering mature forest cover along the Cedar River trail embankment. The right (north) bank is much more disturbed, with a mix of land cover conditions ranging from impervious industrial sites to unmanaged forest. A significant portion of the right bank floodplain between RM 2.0 and RM 4.2 is developed for residential use; in that area there is some forest cover, but it is neither continuous nor dense and consists largely of ornamental (non-native) plant species. Invasive reed canarygrass is pervasive in currently undeveloped portions of the left bank upstream of RM 4.6. Channel migration occurred at this location in response to a 2001 earthquake-induced landslide that temporarily blocked the river. This created a braided channel populated by immature woody vegetation bordered by a narrow woody riparian corridor. Beyond this corridor on the right bank lies the valley wall, and on the left bank Ron Regis Park and State Route (SR) 169. Predevelopment land cover upstream of I-405 was predominantly mixed forest, with coniferous vegetation likely reaching the river banks in more confined valley segments. This area was a locus of early development, so complete clearing and conversion to agriculture and residential development likely occurred earlier than most areas in Puget Sound. Open space and parklands in this part of the assessment area, while extensive in total area, are less intensively developed than the facilities downstream of I-405, with less impact to the river bank and riparian environment. Facilities include: • Cedar River Park/Carco Theater/Renton Community Center – located between RM 1.6 and RM 1.8 on the right bank, with approximately 790 feet of river frontage and comprising approximately 20 acres, including regional trail access, a multi-purpose field, Henry Moses Aquatic Center, open lawn, restrooms, beach/water access, and paved parking. • NARCO Property/Cedar River Dog Park – located at RM 1.7 on the left bank, comprising approximately 24 acres, including regional trail access, non-motorized water access, the City of Seattle’s Broodstock Collection Facility (used for salmon collection and monitoring), and a temporary dog park. • Cedar River Natural Area – located between RM 1.9 and RM 3.9 on the left bank, comprising approximately 250 acres, is a heavily wooded natural area with soft surface nature trails. • Riverview Park – located between RM 2.5 and RM 2.8 on the left and right banks (most of the park is on the right bank), with approximately 2,400 feet of river frontage and comprising 11 acres, includes regional trail access, Cedar River Natural Area access, AGENDA ITEM #1. a) April 2015 Lower Cedar River Chinook Salmon Habitat Restoration Assessment— Existing Conditions and Identification of Potential Site Opportunities and Constraints 5 paved parking, a non-motorized boat launch, a shelter, restrooms, open lawn, and a new clear-span pedestrian bridge and habitat planting to be installed in 2015. • Maplewood Roadside Park – located at RM 2.9 on the right bank, immediately abuts Riverview Park and is just over 1 acre in size, including parking, picnic facilities, and informal water access. • Soos Creek Park and Trails, owned by King County – located between RM 3.9 and RM 4.1 on the left bank, with approximately 1,200 feet of river frontage and comprising 80 acres, including trails and forested areas. Molasses Creek flows through this park on the way to the river. • Maplewood Golf Course – located between RM 4.3 and RM 4.9 on the left and right banks, with approximately 4,000 feet of river frontage and comprising 192 acres, is a full service golf course with cart paths, woodlands, and open lawn. • Ron Regis Park – located between RM 4.9 and RM 5.2 on the left bank, with approximately 2,200 feet of river frontage and comprising 45 acres, 13 acres of which is developed, including regional trail access, a ball field, a soccer field, multipurpose fields, sport courts, parking, and open lawn. Madsen Creek flows through this park on the way to the river. Hydrology Cedar River flows are regulated by the City of Seattle’s Masonry Dam. The dam is managed primarily for drinking water supply, not flood control, so controlled releases are generally secondary to storage and water supply demands. The dam is operated to provide a minimum flow of 70 cubic feet per second (cfs) in the river downstream of it per the Instream Flow Agreement for the Cedar River, but the City of Seattle voluntarily releases greater flow rates depending upon circumstances. Annual low flow, fall salmon spawning flows, and spring salmon outmigration flows are estimated to be 206 cfs, 398 cfs and 807 cfs, respectively (NHC 2014). Spawning and outmigration flows are sustained for extended periods per the Masonry Dam operations requirements. Flood frequency in the lower Cedar River is also affected by the operations of the Masonry Dam. A flood frequency analysis using annual instantaneous peak flow data collected at the USGS Cedar River at Renton gage (Station #12119000) was performed by NHC (2014) for the City’s Cedar River Gravel Removal project. Table 1 summarizes the resultant discharge values. Table 1. Cedar River Peak Discharges. Return Interval Discharge (cfs) 1.01 year 1,150 1.5 year 2,500 2 year 3,000 10 year 5,940 50 year 9,860 100 year 12,000 AGENDA ITEM #1. a) April 2015 Lower Cedar River Chinook Salmon Habitat Restoration Assessment— 6 Existing Conditions and Identification of Potential Site Opportunities and Constraints While the flow attenuation caused by Masonry Dam since 1918 has reduced peak flow rates below what would naturally occur in the lower river, the controlled releases from the dam lead to longer durations of peak flow events, as seen in the January 2009 flood event in which the discharge recorded at USGS gage #12119000 in Renton was consistently in the range of 3,000 to 4,000 cfs for nearly a week. This control also affects average weekly and monthly flows, with discharge being held more consistent throughout the year than would be the case if the dam were not in place. Tributaries in the assessment area include Molasses Creek, Madsen Creek, and two other minor tributaries near RM 4.0 and RM 2.5. Generally these small tributaries are high gradient streams that have small basin areas and highly seasonal flows, with small flow contributions relative to the Cedar River mainstem flow. Flow data are not available for the tributaries. A brief description of each tributary within the study area is presented below, followed by a brief description of existing river side channels and groundwater-fed channels that are connected to the mainstem river channel. Molasses Creek Molasses Creek is a high gradient stream that enters the river near RM 4.1. The first few hundred feet of its channel upstream of the confluence with the Cedar River is lined with concrete and includes two large culverts. The channel gradient is approximately 7% between the river and the first culvert, after which it flattens out to 3% as it passes under the second culvert and across a highly-altered alluvial fan before passing in to a narrow vale where the gradient steepens again to 5%. The mean annual flow in Molasses Creek is estimated at 3.1 cfs (EPA 2014). Madsen Creek Madsen Creek once flowed across an alluvial fan, traces of which extend across the valley in the left bank floodplain around RM 5. The creek itself is now highly altered as it comes off the southern slopes of the valley, where it has been diverted eastward and confined between low berms to pass along the edge of an open space that appears to be associated with the New Life Church to the east. The creek turns sharply left to flow along the south side of SR 169, is routed through a peak flow diversion structure and culverts under SR 169 and 149th Avenue SE, then passes along the eastern and northern edges of Ron Regis Park before discharging to the Cedar River at approximately RM 5.0. There is a small vertical drop in the channel bed at its confluence with the Cedar River that is a moderate fish passage barrier at low flows. Madsen Creek is routed through Ron Regis Park in a narrow corridor confined by a “levee” made of concrete ecology blocks on the west side of the channel, then flows into a large riparian area below the park before discharging into the Cedar River. The channel gradient between SR 169 and its confluence with the Cedar River is currently less than 0.5%. Hence, there is significant sediment build up that causes flooding of adjacent properties. Madsen Creek also has an overflow channel which discharges above the current confluence near RM 5.1. Flow in Madsen Creek is variable depending upon upstream stormwater detention and seasonal flows. Mean annual flow in Madsen Creek is estimated at 3.7 cfs (EPA 2014). AGENDA ITEM #1. a) April 2015 Lower Cedar River Chinook Salmon Habitat Restoration Assessment— Existing Conditions and Identification of Potential Site Opportunities and Constraints 7 Unnamed Tributaries An unnamed tributary stream with a confluence at approximately RM 2.5 drains into an extensive wetland system in the left bank (south) floodplain that is separated from the Cedar River by a relict dike; based upon field reconnaissance performed by Herrera staff, it is unclear where the stream confluence with the river is located. This area is within Riverview Park and adjacent to the Cedar River Trail. An additional unnamed tributary enters the Cedar River near RM 4.0, just downstream of Molasses Creek. This tributary flows into the Cedar River over the Person revetment, which likely is a fish passage barrier at low flows. Existing Side Channels Four completed side channel habitat restoration projects exist within the Lower Cedar River assessment area. The flow in these constructed side channels is a combination of groundwater discharges, backwater from the Cedar River, and through-flow from the river upstream during high flow events. The Renton water utility side-channel is located on the left bank at RM 3.2, but it has not been successful and may not currently have a surface water connection to the Cedar River. The Replacement Side Channel (Rolling Hills) is located just upstream at RM 3.3, and receives flow from the river through a culvert at its upstream end. The King County Elliot Groundwater Channel and the Elliot Rearing/Spawning Side-Channel both connect to the river at their downstream confluence and terminus around RM 4.6; the King County Elliot Groundwater Channel is fed exclusively by groundwater, while the Elliot Rearing/Spawning channel is also connected to the river at its upstream end through a pervious levee section. Hydraulics The Cedar River in the assessment area is generally confined by revetments, road and trail prisms, and intermittent levees, with limited floodplain connectivity and side channel connectivity. Confinement decreases moving upstream away from the lake, but despite the gradual reduction in confinement, there is limited floodplain activation at flow rates less than the 10-year return interval flood event in the lower river reaches. Above RM 4.6, however, there is a mid-channel island with extensive amounts of Large Woody Debris (LWD) and pockets of floodplain connectivity in smaller flow events. The river channel is less confined in this area, with a wide riparian buffer between Ron Regis Park and the Cedar River on the left bank and a connected floodplain area with little development on the right bank. The King County Cedar River flood level viewer (available online at http://www.kingcounty.gov/ environment/waterandland/flooding/maps/cedar-river-flood-flows.aspx) was used to evaluate confinement and floodplain connectivity for this initial habitat restoration assessment. The results indicate that areas near the Madsen Creek confluence inundate between a 1.01-year and a 1.5-year return interval flood event. At a flow rate of 2,800 cfs, which is slightly less than the 2-year return interval peak rate, floodplain inundation is likely in four locations: on the right bank near RM 4.8, on the left bank near RM 4.4, on the right bank downstream of the outlet of Molasses Creek (RM 4.1), and in the areas near the Replacement Side Channel (Rolling Hills). At flows between 2,800 cfs and 6,580 cfs (greater than the 10-year return interval peak), much more of the floodplain is activated in the Ron Regis Park area, near the Molasses Creek confluence, and in the Replacement Side Channel (Rolling Hills) area. AGENDA ITEM #1. a) April 2015 Lower Cedar River Chinook Salmon Habitat Restoration Assessment— 8 Existing Conditions and Identification of Potential Site Opportunities and Constraints The lower Cedar River near the mouth at Lake Washington experiences a “lake effect” from the seasonal lake elevation change that is controlled by the US Army Corps of Engineers at the Hiram Chittenden Locks. Hydraulic analysis by NHC (2014) shows that the lake effect currently extends about 2,000 feet upstream from the Lake Washington shoreline, and following the City’s proposed dredging plan may extend up to 4,000 feet upstream. River Channel Characteristics The average width of the mainstem channel varies from 100 to 200 feet in the assessment area, with relatively low variability downstream of RM 4.6. Channel complexity is low in most of the lower Cedar River, with minimal amounts of stable LWD or other features to create habitat diversity. Coupled with widespread uniformity of bed material and bank armoring, this leaves little in the way of high-flow refugia for migrating fish. Upstream of the “lake effect” described above, this also results in high flow velocities that can scour the bed, hindering sustainability of salmonid redds and success of developing salmonid fish embryos. All of the small tributaries described above are currently perched above the river at low flow and are at least partial barriers to fish passage. Floodplain connectivity at varying levels of flow associated with the presence of salmonids could be greatly improved. Establishing off-channel sites that provide high flow refugia and resting areas for salmonids after stretches of uniform channel conditions would be beneficial. Areas of the floodplain where inundation only occurs in high flow events are prime candidates for possible side channel construction. Where tributary confluences are currently fish passage barriers at low flows, tributary channel restoration would be beneficial. Channel Migration Channel migration is prevented downstream of I-405 under existing conditions. The channel alignment was fixed in 1916, and given ongoing flood protection efforts (i.e., dredging and levee maintenance), it is unlikely that channel migration will resume in this part of the river for the foreseeable future. Prior to development, however, this segment of the river was very dynamic, with widespread channel migration and frequent formation/abandonment of distributary channels likely as the Cedar River’s outlet switched episodically between Lake Washington and the Black River. Channel migration has been highly localized upstream of I-405. Below RM 3.3, confinement of the channel by the valley walls has constrained channel migration historically, and under existing conditions revetments have further confined flow. The only locations in the assessment area where channel migration has been relatively notable are near the Maplewood development (RM 3.3 to RM 4.0), the outlet of Molasses Creek (RM 4.0 to RM 4.2), and at Maplewood Golf Course and Ron Regis Park (RM 4.3 to RM 5.1). Prior to realignment of the lower river and lowering of the Lake Washington water level in 1916, channel migration likely occurred downstream of RM 2, as migration of the river mouth propagated upstream, but fill and revetments have lessened – if not outright eliminated – channel migration opportunities in this area. The area upstream of RM 4.6 is one of the most dynamic reaches in the entire length of the Cedar River (within and upstream of the assessment area). There have been two large AGENDA ITEM #1. a) April 2015 Lower Cedar River Chinook Salmon Habitat Restoration Assessment— Existing Conditions and Identification of Potential Site Opportunities and Constraints 9 landslides emanating north of the river in the vicinity of RM 5.0 within the last century (most recently in 2001), both of which triggered rapid channel migration of as much as 400 feet away from the valley wall. The area remains dynamic as it processes the sediment supplied from the landslide in 2001. Downstream channel response has placed erosive pressure on the left bank near RM 4.9 and the upstream end of Ron Regis Park. Large Wood Presence The confining nature of the revetments on both banks and channelization of the river downstream of I-405 limit large woody debris (LWD) accumulation (King County 2015). Local contribution of LWD from trees in the riparian corridor is also limited. This is contrary to predevelopment conditions, in which LWD likely accumulated in this area in large quantities as the river outlet migrated back and forth from the Black River to Lake Washington. LWD volumes in the channel vary considerably upstream of I-405. Channel confinement and revetment construction between RM 1.6 and RM 4.6, as well as intensive land clearing and patchy development, have reduced LWD volumes and accumulation potential. A significant fraction of the wood in these reaches was placed in coordination with the construction of the four constructed spawning side channels. The area upstream of RM 4.6 has some of the largest LWD volumes per linear foot of channel of any place in the Cedar River corridor. Most of the wood that has accumulated in this area is likely derived locally from the landslide itself and due to bank migration in response to the slide. Post-landside bank migration toward Ron Regis Park has recruited mature vegetation from its forested buffer. Further left bank migration will eventually reach areas of the floodplain that are devoid of woody vegetation, however, limiting future LWD recruitment potential. Aquatic and Riparian Habitat Aquatic and riparian habitat characteristics are described in available literature that has been compiled by the Cedar River Corridor Plan team, some of which was produced for City of Renton projects in recent years. This literature is summarized in Herrera (2015). Key documents describing aquatic and riparian habitat conditions in the lower river include: • Cedar River Basin Plan Current and Future Conditions Report (King County 1993) • Lower Cedar River Basin and Nonpoint Pollution Action Plan (King County 1997) • WRIA 8 Chinook Salmon Conservation Plan (WRIA 8 Steering Committee 2005) • Cedar River Watershed Habitat Conservation Plan (City of Seattle 2000) Fish species considered to be a priority in the Cedar River due to their protected status include Cedar River Chinook, winter steelhead, and bull trout (WDFW 2015, King County 2012). Sockeye salmon are also an important fisheries resource in the Cedar River. Chinook spawn in the Cedar River mainstem, primarily above RM 2. Bull trout are rare in the lower Cedar River, likely due to warm water temperatures that hinder suitable habitat for spawning and rearing. Similarly, most steelhead spawning habitat is located further upstream in the watershed, although rearing and migration habitat is present in the lower reaches in Renton. AGENDA ITEM #1. a) April 2015 Lower Cedar River Chinook Salmon Habitat Restoration Assessment— 10 Existing Conditions and Identification of Potential Site Opportunities and Constraints The lower Cedar River basin has been subject to a wide variety of impacts related to increased human population and urban development. Anthropogenic pressures have resulted in high levels of impervious surfaces, loss of floodplain connectivity, and degraded water quality and riparian habitat. Non-native invasive shrubs including Himalayan blackberry and Japanese knotweed are common throughout the riparian corridor. In addition to the colonization and spread of invasive species, riparian vegetation has been altered from historical conditions due to clearing and disturbance for agriculture and urban development. Where forest cover remains in the assessment area it has been converted from large conifer dominated forests to a deciduous dominated forest. The lower three miles of the Cedar River are heavily channelized and bordered by intensive development. Downstream from the I-405 Bridge at RM 1.6, the river flows through parts of downtown Renton, with the Renton Municipal Airport and Boeing manufacturing complex straddling the river near its mouth at Lake Washington. The flood control facilities in the lower reaches of the Cedar River were constructed by the US Army Corps of Engineers and are owned and managed by the City of Renton, which is the local sponsor. Below RM 1.3, the river flows in a constructed channel that has required continuous maintenance and dredging of the bed elevation for flood protection since 1912. The combination of intensive land uses bordering the straightened channel and ongoing maintenance of the river bed and banks has resulted in minimal fish habitat, and that is expected to be the case for a long time into the future. Upstream of RM 3.3 the river channel is bounded by a series of levees that confine the river and limit side channel and off channel habitat features. Complex in-stream structure is generally absent due to channel simplification associated with these levees. Disconnection of the river from a functioning floodplain reduces available habitat, primarily for Chinook salmon, and limits spawning opportunities and redd success due to scouring winter flows. Between the I-405 bridge at RM 1.6 and the SR 169 bridge at RM 4.3, the south side of the river is mainly public parks and other open space that is forested. However, these open space and park areas are generally at higher elevation than the river and thus are not inundated by flood waters, even in extreme flood events. Thus, they provide good riparian habitats but do not afford opportunity, under existing conditions, for fish habitat use, with the exception of the Corps/Renton Replacement Side Channel at RM 3.3. Highly altered and hardened banks with sparse vegetation cover characterizes the north bank between the two highway bridges. The riparian zone on the north side of the river in this area includes a former concrete batch plant, and residential and commercial development with lawns or ornamental landscaping extending to the river bank. Upstream of the SR 169 bridge, channel migration processes have created more diversity of instream habitat, with development of gravel bars that are generally absent downstream of SR 169 and related accumulation of LWD as described previously. Two off-channel salmon spawning channels have been constructed on the south side of the river adjacent to the golf course, both entering the river at RM 4.6. Historical Contamination An important consideration in evaluating potential habitat restoration sites along the river is whether soil or groundwater contamination may be present in areas that would be excavated AGENDA ITEM #1. a) April 2015 Lower Cedar River Chinook Salmon Habitat Restoration Assessment— Existing Conditions and Identification of Potential Site Opportunities and Constraints 11 and connected to the river. Such contamination would not preclude habitat restoration feasibility and potential, but is nonetheless a factor to consider in comparative evaluation of site options because it could affect the cost and timing of implementing a restoration project. Soil contamination could be a threat to water quality and fish habitat if excavation were to result in the release of toxic materials into surface water. The risk of this type of impact could be managed by remediating the contamination in advance of constructing the remainder of the restoration project (for larger scale contamination), or by using careful construction control measures, and will depend on the nature of the project and additional information on the anticipated presence of contamination in the ground. It will be important to compare a project’s potentially short-term effects on water quality with overall long-term benefits for fish habitat due to site restoration. This is because long-term effects of creating useable habitat and removing sources of contamination may outweigh short-term effects of construction. Herrera completed a regulatory database review to determine if there is documented contamination or concern for potential contamination, and any associated cleanup activities that have occurred, on properties within the floodplain in the assessment area. Sites that have documented releases of hazardous substances or wastes to the environment, and facilities that manage hazardous substances or wastes in significant quantities, are required to report these activities and register with either the US Environmental Protection Agency (EPA) or the Washington State Department of Ecology (Ecology). Both the EPA and Ecology maintain databases to track sites with potential and documented releases of hazardous materials as part of their operations. Documented contaminant releases to the environment, as identified in regulatory agency site files, primarily affect soil and/or groundwater. Releases to soil generally are limited in lateral extent and have limited potential for migration beyond the contamination source area. Releases of contaminants to groundwater tend to extend farther away from the source area and can potentially be encountered during excavation and/or dewatering in areas nearby. Potential contaminant release sites were identified based on the site activity registered with regulatory agencies (i.e., registered underground storage tanks [USTs], hazardous waste generators that must comply with the Resource Conservation and Recovery Act [RCRA], handlers of polychlorinated biphenyls [PCBs]; see the listing of regulatory databases in Attachment B). Potential release sites were identified based on the following categories: • Reported current activities (e.g., hazardous waste generator) • Reported current features (e.g., registered USTs at a service station) • Recorded historical activities (e.g., a former dry cleaner or automobile service station) Sites with a potential for contaminant releases have not been characterized and may or may not have soil and/or groundwater contamination. While this information is not definitive, it provides an indication of where there is greater concern for potential to encounter hazardous materials. Such materials could be encountered during excavation, dewatering, and grading activities, which in turn would add cost to a habitat restoration project and potentially subject construction workers and the public to toxic hazards. AGENDA ITEM #1. a) April 2015 Lower Cedar River Chinook Salmon Habitat Restoration Assessment— 12 Existing Conditions and Identification of Potential Site Opportunities and Constraints Environmental Data Resources, Inc. (EDR), a commercial database service that searches EPA and Ecology records for sites of potential concern, evaluated the project assessment area extending beyond the existing and potential future floodplain on either side of the river, plus an additional ¼-mile distance beyond the floodplain extents. A map of the search area and the database search results are provided in Attachment B. The solid green line shown on the map encompasses the assessment area and the dashed green line indicates the ¼-mile extended search area. A discussion of documented and potential release sites that could affect habitat restoration activities within each of the four study reaches is provided in the following section. None of the sites listed in the regulatory database output have been field verified and there could be some variation from the locations provided in the database search. Summary of Existing Conditions Implications for Habitat Restoration This section to be added to the final version of this report Restoration Opportunities and Constraints There are many opportunities in the assessment area to create or enhance Chinook salmon habitat, some of which have site-specific constraints. In addition, an overarching constraint relates to alterations of existing park features that could be in conflict with master plans that the City has formally adopted for several parks in the assessment area. This section describes site-specific opportunities and potential constraints associated with them. The following discussion is organized by reaches, defined as: • Reach 1 (RM 0.0 – RM 1.6): The Lake Washington Reach • Reach 2 (RM 1.6 – RM 3.3): The Lower Trail Reach • Reach 3 (RM 3.3 – RM 4.6): The Maplewood Reach • Reach 4 (RM 4.6 – RM 5.2): The Landslide Reach Concurrent with this City of Renton project, King County is leading preparation of the Cedar River Corridor Plan, and is using river reaches as a defining geographic basis for much of the planning work. The intention of the corridor plan is to incorporate Chinook habitat restoration project site recommendations and associated concept design plans that result from the City’s project, and to then rank and prioritize those restoration concepts in relation to habitat restoration project concepts to be defined further upriver in the rest of the County’s corridor study area. This process of folding in recommended restoration projects in the City’s jurisdiction will be much smoother to accomplish if both projects use the same reach definitions. Thus, the City’s project uses the same reach definitions in the lower 5.2 miles of the river as are being used for the corridor plan. Figure 1 shows the resultant corridor plan reach break lines. The adoption of the King County reach definitions will not affect identification and analysis of potential Chinook habitat restoration sites along the river within Renton. The City’s commitment to prepare concept designs for up to three restoration sites between River Mile AGENDA ITEM #1. a) April 2015 Lower Cedar River Chinook Salmon Habitat Restoration Assessment— Existing Conditions and Identification of Potential Site Opportunities and Constraints 13 1.0 and 1.6, and up to three additional restoration sites between River Mile 1.6 and 4.2, as stated in its grant that is funding the project, will not change as a result of altering the reach definitions as described herein. Reach 1 (RM 0.0 – RM 1.6): Lake Washington Reach Chinook salmon habitat restoration opportunities in Reach 1 are limited to in-channel work and modifications to the bank immediately adjacent to the channel, as the historical floodplain is disconnected from the river channel by levees and revetments and is occupied by commercial, industrial, and residential properties. A list of specific candidate restoration actions identified in Reach 1 is presented in Table 2. These candidate habitat restoration sites are shown on Figure A-1 in Attachment A. Table 2. Candidate Restoration Actions – Reach 1. River Mile Description 1.1 – 1.6 Place floating riparian vegetation/fish refuge islands along flood walls and the edge of the channel where walkways are not present at or near water level. 1.1 – 1.6 Place mid-channel boulder clusters in planar reaches to generate physical complexity. 1.1 – 1.6 Relocate Cedar River Trail along the right bank between the Senior Activity Center at RM 1.1 and Bronson Way South at RM 1.45, and grade the river bank where the existing trail lies to provide shallow water habitat with LWD and overhanging riparian vegetation. Selected segments along the right bank between Bronson Way South at RM 1.45 and I-405 at RM 1.6 could be considered for similar treatment depending on whether a trail crossing at Bronson Way South is at or below grade. 1.1 – 1.6 Plant native riparian vegetation overhanging the river on the left bank between Logan Avenue North at RM 1.1 and Houser Way South at RM 1.6, exclusive of selected locations at Pedestrian Park (RM 1.1) and Jones Park (RM 1.3) where there are existing river viewpoints. Restoration opportunities in this reach include displacement of either the full length or selected segments of the Cedar River Trail on the right bank between the Senior Center and Bronson Way North. An alternate location for the trail would be immediately upslope from its current location, cantilevered off the existing wall, on the current alignment of North Riverside Drive, or further upslope as described in other planning documents. The trail undercrossing at Logan Avenue North would likely be retained, due to the heavy traffic volumes on that road and the need to separate non-motorized users from traffic. However, on lower volume/speed roads, such as Williams Avenue North and Wells Avenue North, trail users could cross at grade without significant challenges. Alternatives to at-grade crossings at Williams Avenue North and Wells Avenue North would be to ramp down to undercrossings at those streets or to build above-grade trail bridges, depending on the extent and continuity of the habitat restoration effort. The trail undercrossing at Bronson Way South is likely one the City and community would want to retain, given traffic volumes on that road, and the proximity to existing park and trail facilities and several amenities for children. Expansion and/or relocation of the Cedar River Trail is identified in the City Center Community Plan and the Parks, Recreation, and Natural Areas Plan. There may be opportunity to phase trail relocation in a manner that accomplishes immediate goals for restoration along the shoreline without implementing the full plan for the greenway/promenade that constitutes the City Center Neighborhood Park. AGENDA ITEM #1. a) April 2015 Lower Cedar River Chinook Salmon Habitat Restoration Assessment— 14 Existing Conditions and Identification of Potential Site Opportunities and Constraints Other opportunities for habitat restoration in this reach include supplemental riparian planting along the left bank, which will be less controversial but may need to be done selectively. Two small parks in this area both have overlooks at the top of the river bank, and there may be property owners who object to dense screen planting that inhibits their view. The path along the top of the bank includes a narrow strip of managed vegetation that permits views of the river all along its length. Interpretive information about the scope and value of the restoration effort to the health of the river and fish populations would be an important part of gaining support for these types of changes in this highly used and very visible segment of the river. Constraints on restoration work include the requirement that it not reduce flood flow conveyance and the expectation of periodic dredging at the lower end of the reach and transient channel response to dredging in the upper end of the reach. There are several constraints associated with relocating a segment of the Cedar River Trail. These include concerns about losing the views and accessibility to the river that are inherent with the existing trail location, as well as pedestrian safety with relocation of this significant, popular segment of the Cedar River Trail through the heart of the residential and civic community. The replacement trail would have to coexist with a low volume, low speed road, and may involve at-grade road crossings that are currently grade-separated. These changes in roadway character could affect traffic flow, posted traffic speed limits, and other roadside modifications that are challenging to accommodate. Ultimately, with development of the full greenway/promenade that constitutes the City Center Neighborhood Park, some of these challenges would be addressed. In addition, although extensive dredge material characterization sampling did not identify any contamination within the river bed material in the area to be dredged under a separate City project (RM 0 -1.25), the regulatory database review disclosed multiple sites near the river in this reach with known or potential contaminant releases. Twelve such sites are listed within the assessment area, including five documented release sites and seven potential release sites. A summary of the five documented contaminant release sites is as follows: • Soil and possibly groundwater contamination, including metals and non-halogenated solvents, was detected in excavated soil on the Cedar River Trail at RM 0.5. • Two of the release sites relate to surface spills to the Cedar River, one of unknown quantity and the second approximately 300 gallons of diesel fuel at RM 0.6. • Action Aviation has a reported release of petroleum hydrocarbons to soil and groundwater at RM 0.6. • The Renton Municipal Airport Fire Training Area has reported releases of base neutral/acid organics, halogenated organics, and petroleum hydrocarbons to soil and groundwater at RM 0.9. The seven potential contaminant release sites include three RCRA generators, an underground storage tank (UST), an historical automobile service station, a dry cleaner, and a site with a surface water discharge permit. None of these sites has reported releases. AGENDA ITEM #1. a) April 2015 Lower Cedar River Chinook Salmon Habitat Restoration Assessment— Existing Conditions and Identification of Potential Site Opportunities and Constraints 15 Thirty three additional sites of potential concern for contamination releases were listed within ¼-mile of the floodplain, including 10 to the north of the river and 23 to the south. Four of the sites to the south reported releases to groundwater, including the following: • Renton Municipal Airport at RM 0.5 • Puget Sound Helicopter at RM 1.0 • Renton School District at RM 1.0 • Castaway Restaurant at RM 1.1 One site to the north of the river, a Texaco/Shell station at RM 1.5, reported a release of petroleum hydrocarbons. Contamination from all of the sites with releases to groundwater could potentially migrate to the floodplain. If restoration actions are proposed at a location that is downgradient of the groundwater flow direction relative to any of these sites of concern, additional analysis of contamination potential should be performed. Reach 2 (RM 1.6 – RM 3.3): Lower Trail Reach In Reach 2 Chinook salmon habitat restoration opportunities are associated with softening existing steep and/or armored banks, widening the narrow riparian zone in places, enhancing existing side-channels, and reconnecting tributaries to the mainstem during low flow. A list of specific candidate restoration actions identified in this reach is presented in Table 3. These candidate habitat restoration sites are shown on Figure A-2 in Attachment A. Table 3. Candidate Restoration Actions – Reach 2. River Mile Description 1.7 Remove concrete wall, terrace banks, and plant riparian vegetation on right bank at Carco amphitheater. Add LWD or floating riparian vegetation/fish refuge island at river’s edge. 1.8 Remove unused/obstructed boat ramp and revegetate bank. 1.9 Acquire all or part of construction equipment storage site on right bank at River Mile 1.9. Remove revetments and detention basins and plant riparian vegetation along river banks. 2.4 Restore sediment and fish passage to tributary stream at 6' culvert under Cedar River Trail. 2.6 Remove wetland-impounding dikes at RM 2.5, reconnect tributary channel to river. 3.2 Restore low-flow connectivity of side-channel at RM 3.2. 3.3 Connect perennial inflow at upstream end of abandoned spawning channel at RM 3.2. Restoration opportunities along Reach 2 may offer some of the highest interpretive or education value for the general public. The setting, close to downtown Renton but with a more sinuous channel and native vegetation than exists in Reach 1, provides a more natural context, making restoration efforts appear to be less contrived and more cost effective to the casual observer. The Carco Amphitheater could be an ideal site from the standpoint of educating the public about salmon habitat restoration efforts, as it is adjacent to the Community Center and is a AGENDA ITEM #1. a) April 2015 Lower Cedar River Chinook Salmon Habitat Restoration Assessment— 16 Existing Conditions and Identification of Potential Site Opportunities and Constraints common site from which news reporters document flood events. This site may be well suited for natural riverine habitat, while continuing to provide pedestrian access to the river’s edge. In the vicinity of RM 1.7 to RM 2.4 on the left bank, there is a wide area currently occupied by an off-leash dog park but planned for major park expansion as part of the Tri-Park Plan. It may be possible to refine the Plan with the addition of specific restoration efforts, but the active recreation program that includes the regional trail, sportsfields, parking, and support facilities would have to be retained. The Tri-Park Plan has been adopted by the City as part of proposed I-405 improvements and the associated EIS. Restoration of sediment and fish passage at RM 2.4 may be accomplished in a number of ways, but could offer greatest interpretive value if the solution were visible to the public. The City is currently undertaking a project to construct Improvements at Riverview Park, including a new clear span pedestrian bridge, invasive plant removal and enhanced riparian planting along the left bank. There are numerous informal, user-created soft-surface trails throughout the Cedar River Natural Area, several of which access the river along its length on the left bank. Some of these river access points may be in locations where frequent pedestrian access has a negative impact on bank stability or creates excessive siltation in the river. It may be beneficial to re- route some trails, install fencing, barricades, or dense planting to redirect access to less vulnerable areas along the river bank, or pervious types of bank hardening to prevent siltation and erosion at the access points. Constraints affecting habitat restoration potential in this reach include narrowness of the riparian zone, existing commercial land uses along the right bank, and limited construction access along the left bank where most restoration opportunities are located. In addition, the regulatory database review disclosed multiple sites with known or potential contaminant releases in this reach. Eight sites of potential concern for contaminant releases were listed within the project area in this reach, including six documented release sites and two potential release sites. One of the release sites, Stoneway Concrete Renton, located northeast of the river at RM 2.1, was identified with a release of petroleum hydrocarbons, metals, and volatile organic compounds to soil and possibly groundwater. Four of the documented contaminant release sites have been reported cleaned up and the fifth, a spill of unknown quantity or material that likely occurred along a paved road northeast of the river at RM 2.8, was likely of limited quantity and would not impact the project area. Thus, the primary concern for potential soil or groundwater contamination in this reach is the Stoneway Concrete Renton property. Two potential release sites include an historical service station and an historical auto repair facility, located northeast of the river at RM 2.1 and RM 3.1, respectively. Neither of these sites had reported releases. Thirteen additional sites of potential concern for contamination releases were listed within ¼-mile of the floodplain, five to the south of the river and eight to the north. None of the sites to the south reported releases to groundwater, but one site northeast of RM 3.0 AGENDA ITEM #1. a) April 2015 Lower Cedar River Chinook Salmon Habitat Restoration Assessment— Existing Conditions and Identification of Potential Site Opportunities and Constraints 17 (Olympic Pipeline) reported groundwater contamination that may have migrated into the floodplain. Reach 3 (RM 3.3 – RM 4.6): Maplewood Reach Chinook salmon habitat restoration opportunities in Reach 3 include revetment removal, reconnection of left bank tributaries and consequent widening of the riparian zone, and widening the active channel at the SR 169/Cedar River Trail crossing. A list of specific candidate restoration actions is presented in Table 4. These candidate habitat restoration sites are shown on Figure A-3 in Attachment A. Table 4. Candidate Restoration Actions – Reach 3. Number Description 4.0 A Remove revetment downstream of bluff at River Mile 4.0. 4.0 B Restore fan (old gravel pit/landslide) above revetment and connect tributary stream to river. 4.1 Remove and replace concrete-lined streambed grade control in Molasses Creek near confluence with Cedar River. Restore Lower Molasses Creek fan upstream of upper access road. 4.3 Remove and replace Cedar River Trail bridge and reroute trail to eliminate drainage from the trail into the river, and increase available channel width. 4.4 Place mid-channel boulder clusters in planar reaches to generate physical complexity. The confluence of Maplewood Creek with the Cedar River occurs at RM 3.35. One option to enhance habitat and education value at this location would be to reconstruct the trail on a clear-span bridge or boardwalk to widen the channel connection. The Maplewood residential community, with maintained backyards along the river, has a significant impact on the right bank of the river from RM 3.4 to RM 4.2. Property owners have built informal trails, patios, or otherwise cleared vegetation from the river bank. There may be an opportunity to provide incentives for residents to revegetate the bank through education about the need for salmon habitat restoration, including financial assistance, or via seeking volunteers for replanting efforts. Restoration constraints include the questionable stability of the old gravel pit impoundment berms at Molasses Creek and in the Person revetment fan, the SR 169 bridge (which would be very expensive to modify), and the extensive residential development in the Maplewood neighborhood. In addition, the regulatory database review disclosed two potential contaminant release sites in and near the floodplain in this reach. One of the sites was an historical dry cleaner located along the road northeast of the river at RM 4.3; the second was reported as side channel activity southwest of the river at RM 3.3. Six additional sites of potential concern for contaminant releases were listed within ¼-mile of the floodplain in the assessment area, but none reported groundwater contamination that could potentially migrate into the floodplain. AGENDA ITEM #1. a) April 2015 Lower Cedar River Chinook Salmon Habitat Restoration Assessment— 18 Existing Conditions and Identification of Potential Site Opportunities and Constraints Reach 4 (RM 4.6 – 5.2): Landslide Reach This reach has the most potential for widening the active channel zone and/or recreating a complex side-channel network to restore and enhance Chinook salmon habitat. It is also the only reach in Renton in which Chinook spawning has been observed outside of constructed spawning channels. The Madsen Creek alignment in particular has many opportunities for improvement. A list of specific candidate restoration actions is presented in Table 5. These candidate habitat restoration sites are shown on Figure A-4 in Attachment A. Table 5. Candidate Restoration Actions – Reach 4. Number Description 4.7 Direct perennial flow into the Elliot Rearing/Spawning Side-Channel at RM 4.55 – RM 4.85. 4.9 A Reconnect blind slough at RM 4.9 to Cedar River. 4.9 B Remove or replace failing geogrid at old side-channel alignment and plant native riparian vegetation after invasive vegetation removal. 5.0 Comprehensive or piecemeal restoration of the lower reach of Madsen Creek. A Reconfigure Madsen Creek – Cedar River confluence to eliminate low-flow fish-passage barrier. B Remove debris, construct trail bridge downstream of Madsen Creek floodplain distributary confluence. C Realign and replant braided section of Madsen Creek away from Ron Regis Park cricket field, D Plant native trees along the west side of Madsen Creek at the eastern edge of Ron Regis Park. E Remove blackberry, plant native trees along the left bank of Madsen Creek downstream of 149th Ave SE. F Fix 149th Ave SE culvert to eliminate bypass into 149th Ave SE ditch and restore fish passage. G Enlarge SR 169 culvert and restore riparian vegetation along Madsen Creek south of SR 169. H Reconfigure Madsen Creek sewer crossing/bypass structure and swale to facilitate fish passage. 5.3 Remove oldest Elliott Bridge left-bank abutment at River Mile 5.3 to allow downstream channel migration or connection to constructed side-channels in Ron Regis Park riparian buffer. Principal constraints to restoration actions in Reach 4 are the presence of the Ron Regis Park sports and multi-use fields, the golf course and related infrastructure at the lower end of the reach, the risk of channel migration rendering restoration actions ineffective or a wasted investment, and the complexity of the Madsen Creek bank and culvert infrastructure at SR 169. The access road alignment and multi-use field configuration at Ron Regis Park could be modified to maximize restoration opportunities for Madsen Creek. The adopted master plan for Ron Regis Park utilized wetland buffer averaging, shoreline setbacks, and floodplain mapping to maximize the active use area of the park, dictating the layout and locations for fields and infrastructure. There may be limited opportunity for relocation of certain amenities. There are no documented or potential contaminant release sites listed within the assessment area in this reach. Seven sites were listed within ¼-mile of the floodplain in this area, but none of these sites reported groundwater contamination that could potentially migrate into the floodplain. AGENDA ITEM #1. a) April 2015 Lower Cedar River Chinook Salmon Habitat Restoration Assessment— Existing Conditions and Identification of Potential Site Opportunities and Constraints 19 Next Steps Solicit Stakeholder Input on Candidate Restoration Actions Herrera will assist the City in convening a meeting with representatives identified by the City as the stakeholder group to obtain input on the candidate restoration site areas identified herein, and to discuss site evaluation criteria and metrics to be applied in detailed analysis of potential restoration sites. Stakeholder comments on the candidate restoration sites will be reflected in the final version of this report. Define Restoration Site Layouts and Impacted Land Uses For each candidate restoration action retained in the final version of this report, Herrera and MacLeod Reckord will prepare a layout sketch and a list of unique site issues/features. The site layouts and listing of issues of interest for each will reflect input obtained from stakeholders. These sketches will be submitted to the City for review and concurrence on the general configuration before detailed site analyses are performed. Analyze Performance and Feasibility of Candidate Restoration Sites Using criteria and metrics defined and discussed with stakeholders, Herrera will conduct an analysis of the quantity and quality of Chinook salmon habitat that could be formed by each candidate restoration action. The analysis will also consider issues affecting feasibility of implementation, and mitigation that could be required for impacts to park and/or trail facilities or for other impacts. Additional field reconnaissance will be performed as needed to support this analysis. Quantitative and qualitative metrics will be used to assess potential habitat gain and ecological lift. Prepare a Restoration Site Potential and Feasibility Analysis Report Herrera will prepare a report documenting the analyses described above, with input from MacLeod Reckord regarding parks and recreational facilities and amenities. The report will include information presented herein, plus an evaluation of existing restoration projects within and near the City of Renton on the Cedar River, a description of the information used in performing detailed analysis of each candidate restoration site, a concept sketch of each site evaluated, a comparative matrix listing pros and cons of each site, concept sketches for displaced and/or modified active/passive recreational facilities, and recommendations for the sites that should be carried forward for conceptual design. Develop Concept Designs Herrera and MacLeod Reckord will prepare conceptual designs and associated narrative information in accordance with RCO Manual 18, Appendix D-1, for up to three restoration sites between RM 1.0 and RM 1.6 and up to three restoration sites upstream of RM 1.6. Public Outreach Final draft results of the project will be shared with the public and stakeholders via a public meeting or other public outreach to be conducted for the King County Cedar River Corridor AGENDA ITEM #1. a) April 2015 Lower Cedar River Chinook Salmon Habitat Restoration Assessment— 20 Existing Conditions and Identification of Potential Site Opportunities and Constraints Plan Project. Public and stakeholder input at this stage will be reflected in the final concept designs and the final version of the Restoration Site Potential and Feasibility Analysis Report. References City of Seattle. 2000. Final Cedar River Watershed Habitat Conservation Plan. Prepared by Seattle Public Utilities. Seattle, Washington. April 2000. EPA. 2014. WATERS Data v1.6.kmz. US Environmental Protection Agency online geospatial information accessed at: http://water.epa.gov/scitech/datait/tools/waters/tools/waters_kmz.cfm Herrera. 2014. Cedar River Corridor Plan Literature Prioritization and Data Gaps. Memorandum prepared for Nancy Faegenburg of King County Department of Natural Resources and Parks Water and Land Resources Division by Herrera Environmental Consultants, Seattle, WA. December 4, 2014. JGM. 2006. Tri-Park Master Plan (Liberty Park, Cedar River Park, and Narco Site). Prepared for City of Renton Community Services by JGM Landscape Architects, Bellevue, Washington. King County. 1993. Cedar River Basin Plan Current and Future Conditions Report. Prepared by King County Department of Public Works, Surface Water Management Division. April 1003. King County. 1997. Lower Cedar River Basin and Nonpoint Pollution Action Plan. Prepared by King County Department of Natural Resources and Cedar River Watershed Management Committee. July 1997. King County. 2012. King County Programmatic Habitat Assessment. King County Department of Natural Resources and Parks, Water and Land Resources Division. June 2012. King County. 2015. Draft Cedar River Large Wood Study. Publication pending. MacLeod Reckord et al. 2009. Renton Trails and Bicycle Plan. Prepared for City of Renton by MacLeod Reckord Landscape Architects, Seattle, WA in association with Transportation Engineering Northwest and Andrew Goulding AIA SEGD. Adopted May 11, 2009. MAKERS and The Transpo Group. 2011. City Center Community Plan. Prepared for City of Renton Department of Community & Economic Development by MAKERS architecture and urban design, Seattle, WA in association with The Transpo Group. Adopted June 6, 2011.MIG. 2011. Parks, Recreation and Natural Areas Plan. Prepared for City of Renton by MIG, Portland, OR. Adopted November 2011. NHC. 2014. Hydraulic Analysis – Cedar River Gravel Removal Project. Technical memorandum prepared for Coast & Harbor Engineering, Inc. by Northwest Hydraulic Consultants, Inc., Seattle, Washington. WDFW. 2015. Salmonscape web mapping system. Washington Department of Fish and Wildlife. http://apps.wdfw.wa.gov/salmonscape/map.html (accessed February 6, 2015). WRIA 8 Steering Committee. 2005. WRIA 8 Chinook Salmon Conservation Plan. AGENDA ITEM #1. a) ATTACHMENT A Potential Restoration Site Maps AGENDA ITEM #1. a) REACH 1Cedar River Liberty Park Pedestrian Park Jones Park Senior Activity Center Cedar River Park NARCO Property Dog Ce d a r R i v e r T r a i lCedar R iver Tra i l 1.1 - 1.6 Renton Lake Washington 405 900 167 900 900HARDIE AVE SWS 2ND ST GARDEN AVE NSUNSE T BLVDNEB R O N S O N WAYN N E P A R K DR WILLIAMS AVE SWELLS AVE N87TH AVE S85TH AVE SN 4TH ST N 6TH ST HOUSERWAYNLOGANAVENN 3RD ST S 4TH ST S 3RD ST WELLS AVE SSW S U N S E T B LV D PELLY AVE NHOUSE R W A Y SRAINIERAVES BRONSONWAYNEBURNETT AVE SPARK AVE NRENTO N A V E SRAINIER AVE NSTEVENS AVE NWSUNSET BLVD NN 8TH ST ABERDEEN AVE NEN R I VERSIDE DR RM1 RM2 1.91.81.7 Renton Municipal Airport K:\Projects\Y2014\14-05933-000\Project\Reach_Opportunity\reach_opp_set.mxd (1/13/2015) 01,2002,400600Feet Legend Reach break Restoration opportunity Trail River mile 1/10th-river mile City limit Lake Washington Newcastle Renton Tukwila Figure A-1. Reach 1 - Restoration Opportunity Along the Cedar River, Renton, Washington. AGENDA ITEM #1. a) REACH 2 Cedar R i v e r Liberty Park ivity Center Cedar River Park NARCO Property Dog Park Riverview Park Cedar River Natural Area Maplewood Roadside Park Ce d a r R i v e r T r a i l Ced Cedar River Natural Area - 1.6 Renton 405 900 RENTONAVESCEDAR AVE SR O L LINGHILLSAVESEL A K EYOUNGSWAYSE NE 4TH ST MONROEAVENESE 5TH STPARK AVE NGRANTAVESNE 3RD S T EDMONDSAVENEPUGET DR SESEROYAL H IL L S D R RM3 RM2 3.33.2 2.62.4 1.91.81.7 K:\Projects\Y2014\14-05933-000\Project\Reach_Opportunity\reach_opp_set.mxd (1/13/2015) 01,2002,400600Feet Legend Reach break Restoration opportunity Trail River mile 1/10th-river mile City limit Lake Washington Newcastle Renton Tukwila Figure A-2. Reach 2 - Restoration Opportunity Along the Cedar River, Renton, Washington. AGENDA ITEM #1. a) REACH 3 Ce dar R i v e r Ceda r R i v e r T r a i l Cedar River Natural Area Maplewood Golf Course Maplewood Neighborhood Soos Creek Park and Trails Renton Mo l a s s es Cr e e k SERENTONMAPLEVALLEYRD RM4 4.7 4.4 4.3 4.1 4.0B 4.0A 3.3 K:\Projects\Y2014\14-05933-000\Project\Reach_Opportunity\reach_opp_set.mxd (1/13/2015) 0 600 1,200300Feet Legend Reach break Restoration opportunity Trail River mile 1/10th-river mile City limit Lake Washington Newcastle Renton Tukwila Figure A-3. Reach 3 - Restoration Opportunity Along the Cedar River, Renton, Washington. AGENDA ITEM #1. a) REACH 4 Cedar Riv e r Maplewood Golf Course Cedar Ri v e r T r a i l Ron Regis Park 5.0 Renton Madson Creekasses Creek SE 144TH ST SE RENT O N M A P L E V A L L E Y R D 140TH WAYSE RM5 4.9A 5.3 HG FE D C BA 4.9B 4.7 K:\Projects\Y2014\14-05933-000\Project\Reach_Opportunity\reach_opp_set.mxd (1/13/2015) 0 600 1,200300Feet Legend Reach break Restoration opportunity Trail River mile 1/10th-river mile City limit Lake Washington Newcastle Renton Tukwila Figure A-4. Reach 4 - Restoration Opportunity Along the Cedar River, Renton, Washington. AGENDA ITEM #1. a) ATTACHMENT B Regulatory Database Output of Documented and Potential Contaminant Release Sites AGENDA ITEM #1. a) .320440440 400480 2004004040 40 80 80 20 120 160200 200240 240280 280320320 320 320360360360360360 440 520480 480440440 440 440 400 40040040040040 0 400360320520 520520 400 40 0 400400 320480 480240 240 360 200 200160120120 20440 44080 8040 40400400 400 400400320 8036080 360 360 360360360360 36036032 0 3 203203203203203 20 280 280280 280280 280280280280280280 240 240240240240240240240200 200200200200200200160 160160160160160160280360 200440480400400400400 400480 4400440 440 440 404040404040 40 40 80 808080 80808080808080 80 80120120120120120120120120120120120120 120 120160160160 160 160160160 160 200 200200 200 2 00200200 200 200 200240240 240 240240240 240240240 240280 280 280 280280280280280 280280280320320320 320 320320320 320320 320320 360360 360360360360360360360360360 400 400 400400400 400400 400440440 44 440)LJXUH%EDR DataMapArea Study122 12 00122 10 00122 08 0047 28 0047 30 0047 28 0047 30 00 122 12 00122 10 00122 08 00AGENDA ITEM #1. a) APPENDIX B Concept Designs and Cost Estimates for Highest Ranked Restoration Sites AGENDA ITEM #1. a) Chinook Salmon Habitat Restoration Site No. 1 AGENDA ITEM #1. a) November 2015 Lower Cedar River Chinook Salmon Habitat Restoration Assessment Habitat Restoration Site Potential and Feasibility Analysis Report B-1 Concept Design Narrative for Lower Cedar River Chinook Salmon Habitat Restoration Site No. 1 Project Site Description This site is currently a lawn area adjacent to the right bank of the river just upstream of Logan Avenue North. The restoration work would entail excavating a shallow semi-circular alcove linked to the main stem river at all flow levels; placing a large wood engineered structure at the downstream edge of the alcove to prevent erosion of the bank where flow re-enters the main stem, and to encourage creation of a scour pool and cover for juvenile salmon; and planting native vegetation on the perimeter of the alcove, and along the river bank between the alcove and the Logan Avenue North bridge abutment. Because this lawn area is a popular location for a variety of purposes, a railing would be placed on the edge of the alcove to discourage people from entering the water, while giving them access to see and learn about the habitat that is created. Goals and Objectives for Addressing Existing Chinook Salmon Habitat Problems This restoration project would support an overall goal of salmon recovery in WRIA 8, which is to restore habitat for Chinook salmon in the lower Cedar River where much of the historical habitat for this species has been lost due to development along the river and in its floodplain. Specific habitat restoration objectives that this project would address are creation of shallow, low velocity edge habitat with overhanging native vegetation that supports juvenile Chinook rearing and refuge from high flows in the river. Concept Design Description The attached site plan and cross-section sketches show the dimensions and specific features of this restoration project concept. Specific elements of the design include the following: • The alcove would be excavated to have a bottom slope ranging from 5H:1V to 10H:1V. • The inland edge of the alcove would be defined by a low terraced wall supported by large boulders (preferably) or made of concrete (if necessary) with native vegetation planted on the terraces. • Sandy substrate would be placed, and would be sustained naturally for the long-term by sand transported from upstream. • The shape of the alcove would promote a balance of low-velocity flows during most river flow conditions, with high enough velocity to prevent unwanted aggradation. Stakeholder Comments and Other Project Considerations Interpretive signage should be included along the railing and walk focusing on salmon habitat creation. To the extent practical, given other uses of the lawn and balancing the desire for public education opportunity, tree and shrub plantings should be used to maximize shade benefits. AGENDA ITEM #1. a) November 2015 Lower Cedar River Chinook Salmon Habitat Restoration Assessment B-2 Habitat Restoration Site Potential and Feasibility Analysis Report The tree and shrub plantings would also help to reduce artificial light penetration into the alcove. Construction Cost Estimate A construction estimate for this project is attached. AGENDA ITEM #1. a) Engineering Construction Cost Estimate for Conceptual Design Project Name: Cedar River: Site 1Project Number: 14-05933-000Client: City of Renton QA Review Completed/Updated By: IBM Last Updated On: 10/12/2015 Approved By: ME Approved On.:10/12/2015 Item No. WSDOT Std Item No. Spec Section Item Description Qty Sub Item Qty Unit Unit Cost Sub Item Cost Total Cost Div 1 General Requirements1 Mobilization 1 L.S. 8% 7,510$ 2 Erosion/Water Pollution Control 1 L.S. 5% 4,694$ Div 2 Earthwork3 General Excavation, Incl. Haul 350 C.Y. 15$ 5,250$ Div 3 Aggregate Production and Acceptance Div 4 Bases 4 Sand Substrate 38 C.Y.40$ 1,520$ Div 5 Surface Treatments and Pavements 5 Brick Path, Incl. Materials and Labor 1500 S.F.24$ 36,000$ Div 6 Structures 6 0909 Large Boulders (4-man) for Rock Wall 74 C.Y.140$ 10,360$ 7 7167 Backfill for Rock Wall 33 C.Y.27$ 891$ Div 7 Drainage Structures, Storm Sewers, Sanitary Sewers, Water Mains, and Conduits Div 8 Miscellaneous Construction8Work Area Isolation From the River (e.g. bulk bags) 100 L.F.120$ 12,000$ 9 4410 Railing, Type Ornamental Steel 114 L.F.110$ 12,540$ 10 LWD Structure 1 L.S.6,140$ 6,140$ 11 Riparian Planting 1530 S.F.6$ 9,180$ Construction Subtotal 106,086$ Surveying 5,000$ 5,000$ Design 30,000$ Permitting 15,000$ Construction Management 20%21,217$ Subtotal with Allied Costs 177,300$ Contingency 50%88,650$ Tax 9.5%10,078$ Total (with Contingency and Tax) 276,000$ Cost Estimate Template: Herrera APWA O:\proj\Y2014\14-05933-000\Calcs\Cost Estimate\CostEst_Site1.xlsm Printed On: 10/12/2015 Page 1 of 1 AGENDA ITEM #1. a) CEDAR RIVER TRAILRIVER MILE 1.1345411232 Create shallow alcove in lawn area between Senior Activity Center and the existing river bank.30 ft60 ftbank- full width 117 ft CEDAR RIVERRiver-rock retaining wall with ornamental native shrubs in continuous terraced planters.Shallow sandy alcove/beach.Large woody debris keyed into bank. Path along beach retaining wall.5Native riparian planting.A’A LOWER CEDAR RIVER:SITE 1200204010FEETAGENDA ITEM #1. a) bank- full discharge1000 cfs500 cfsexisting ground surfaceA A'12341234River-rock retaining wall with ornamental native shrubs in continuous terraced planters.Shallow sandy alcove/beach.Large woody debris keyed into bank at downstream edge of the alcove. Pedestrian path along beach retaining wall. 505102.5FEETLOWER CEDAR RIVER:SITE 1AGENDA ITEM #1. a) Chinook Salmon Habitat Restoration Site No. 2 AGENDA ITEM #1. a) November 2015 Lower Cedar River Chinook Salmon Habitat Restoration Assessment Habitat Restoration Site Potential and Feasibility Analysis Report B-9 Concept Design Narrative for Lower Cedar River Chinook Salmon Habitat Restoration Site No. 2 Project Site Description This site encompasses a 0.3-mile-long section of the Cedar River Trail along the right bank of the river between Bronson Way North and the Renton Senior Activity Center. The existing lower trail is overtopped by flow in the river whenever the water level is running moderately high, several times a year. An existing upper trail located north of North Riverside Drive at the intersection of Williams Avenue North would remain. The restoration work would entail removing the lower pedestrian trail paving and the gabions that support the waterward edge of the trail fill prism, and excavating a shallow habitat bench linked to the main stem river at all flow levels. The existing retaining wall between the trail and North Riverside Drive would not be modified. Because this is a popular pedestrian trail segment for City residents and visitors, the trail would need to be relocated up onto North Riverside Drive, necessitating elimination of one lane of vehicular traffic on the street. Goals and Objectives for Addressing Existing Chinook Salmon Habitat Problems This restoration project would support an overall goal of salmon recovery in WRIA 8, which is to restore habitat for Chinook salmon in the lower Cedar River where much of the historical habitat for this species has been lost due to development along the river and in its floodplain. Specific habitat restoration objectives that this project would address are creation of shallow, low velocity edge habitat with overhanging native vegetation that supports juvenile Chinook rearing. Concept Design Description The attached site plan and cross-section sketches show the dimensions and specific features of this restoration project concept. Specific elements of the design include the following: • The habitat bench beneath the existing trail footprint would be excavated to have a bottom slope of 3H:1V. • The inland edge of the bench is an existing linear planter at the base of the retaining wall – native overhanging vegetation would be planted in this linear feature. • Native river rock and alluvium would be placed for the bench substrate. • Native wetland plants would be installed on the bench. Stakeholder Comments and Other Project Considerations The existing lower trail between Bronson Way North and the Renton Senior Activity Center is for pedestrian use only. Relocating the trail up to North Riverside Drive would likely invite multi-modal use. (Note, the existing upper trail located between Williams Avenue North and the Renton Senior Activity Center is currently multi-modal). The proposed 10-foot-wide trail is the minimum width for multi-use trails (12-foot width is preferred). Shoulders 2 feet wide AGENDA ITEM #1. a) November 2015 Lower Cedar River Chinook Salmon Habitat Restoration Assessment B-10 Habitat Restoration Site Potential and Feasibility Analysis Report on each side of the trail need to be added for a 14-foot total trail width per the adopted City of Renton Trails and Bicycle Master Plan. To the extent practical given the limited space for plantings on the landward edge of the new habitat bench, taller growing trees should be used to maximize shade benefits and limit artificial light penetration to the river and the new habitat bench. To avoid potential scour at existing bridge abutments, the habitat bench design at each bridge undercrossing will need to be tailored to prevent inducing a scour problem. This may require buttressing the landward edge of the new bench to sufficient depth with large boulders or riprap to resist scour. Construction Cost Estimate A construction estimate for this project is attached. AGENDA ITEM #1. a) Engineering Construction Cost Estimate for Conceptual Design Project Name: Cedar River: Site 2Project Number: 14-05933-000Client: City of Renton QA Review Completed/Updated By: IM Last Updated On: 9/24/2015 Approved By: ME Approved On.:10/12/2015 Item No. WSDOT Std Item No. Spec Section Item Description Qty Sub Item Qty Unit Unit Cost Sub Item Cost Total Cost Div 1 General Requirements1 Mobilization 1 L.S. 8% 35,962$ 2 Erosion/Water Pollution Control 1 L.S. 3% 13,486$ Div 2 Earthwork3 General Excavation, Incl. Haul 1,220 C.Y. 15$ 18,300$ 4 Sawcut Asphalt Conc. Pvmt (on Riverside Dr. N.) 1,105 L.F. 2$ 2,210$ 5 0108 Removing Cement Conc. Curb and Gutter 1,105 L.F. 13$ 14,365$ 6 0120 Removing Brick Path and Asphalt, Incl. Haul 2,920 S.Y.10$ 29,200$ 7 Removing Catch Basins 5 Each 1,000$ 5,000$ Div 3 Aggregate Production and Acceptance Div 4 Bases8Streambed Substrate 410 C.Y.60$ 24,600$ Div 5 Surface Treatments and Pavements9New Trail on Edge of Riverside Drive N.1,105 L.F.95$ 104,975$ Div 6 Structures Div 7 Drainage Structures, Storm Sewers, Sanitary Sewers, Water Mains, and Conduits 10 6700 Conc. Curb and Gutter 1,105 L.F.28$ 30,940$ 11 3090 Catch Basins, Type 2 5 Each 3,200$ 16,000$ Div 8 Miscellaneous Construction 12 Work Area Isolation From the River (e.g. silt curtain, bulk 1,600 L.F.120$ 192,000$ 13 Riparian Planting 0.4 Acre 30,000$ 11,935$ Construction Subtotal 498,973$ Surveying 15,000$ Design 20%99,795$ Permitting 15%74,846$ Construction Management 20%99,795$ Subtotal with Allied Costs 788,400$ Contingency 50%394,200$ Tax 9.5%47,402$ Total (with Contingency and Tax) 1,230,000$ Cost Estimate Template: Herrera APWA O:\proj\Y2014\14-05933-000\Calcs\Cost Estimate\z-obs CostEst_Site2.xlsm Printed On: 10/13/2015 Page 1 of 1 AGENDA ITEM #1. a) JONES PARKB’B N 1st StN Riverside Dr.S Riverside Dr.Williams Ave. N Wells Ave. NPelly Ave. NPark Ave. NBronson Way N4123Excavate shallow bench at 3:1 slope beneath existing trail footprintto N. Riverside Drive corridorNative riparian vegetation on existing embankment/planterPreserve existing vegetation at edge of ROW Pedestrian and shared use path relocated to N. Riverside Drive roadway, with vehicular traffic reduced to one way on the roadway5Existing shared use path 66Existing pedestrian path LEGENDparcel boundaryRiver MileRM12 345RM 1.2RM 1.4RM 1.3Replace existing trail at river level with a shallow habitat bench and relocate trail to N. Riverside Drive corridor700 ft25 ft (typ)405 ft470 ft120 ft (bank-full width)Cedar RiverCEDAR RIVER TRAILLOWER CEDAR RIVER:SITE 2120012024060FEETAGENDA ITEM #1. a) 1000 cfs500 cfsbank- full dischargeExcavate shallow bench at 3:1 slope beneath existing trail footprint and place large river rock, native alluvium, and native riparian plantings on bench. Preserve existing vegetation at edge of right-of-wayPedestrian and shared use path relocated to N. Riverside Drive roadway, with vehicular traffic reduced to one way on the roadwayPlan View Note does not shown on this section.15122334 N Riverside DrRight-of-WayCedar River Native riparian vegetation on existing planter terraceB’B4existing 8’ Cedar River Trail (pedestrian only)10’-0”existing ground surface505102.5FEETLOWER CEDAR RIVER:SITE 2AGENDA ITEM #1. a) Chinook Salmon Habitat Restoration Site No. 3 AGENDA ITEM #1. a) November 2015 Lower Cedar River Chinook Salmon Habitat Restoration Assessment Habitat Restoration Site Potential and Feasibility Analysis Report B-17 Concept Design Narrative for Lower Cedar River Chinook Salmon Habitat Restoration Site No. 3 Project Site Description This site is currently a 0.3-mile-long section of the Cedar River Trail along the right bank of the river between Bronson Way North and the Renton Senior Activity Center. The site encompasses two block lengths of a neighborhood street (North Riverside Drive), a block length of an existing upper shared used path extending north of North Riverside Drive at the intersection of Williams Avenue North, landscaping between the street/path and the river, and a 0.3-mile-long section of the lower Cedar River Trail along the right bank of the river. The lower pedestrian trail is overtopped by flow in the river whenever the water level is running moderately high, several times a year. The City is planning a large-scale neighborhood redevelopment project that includes modified connections to the river in this area as per the adopted City Center Community Plan. The habitat restoration work would entail removing the lower trail paving and gabions that support the waterward edge of the trail fill prism, removing the retaining wall between the trail and the street/shared path above (inland of) it, removing street paving and the existing shared use path at the north end of the site, excavating a swath of land between the river and the redeveloped area to the northeast, and creating shallow edge habitat with large woody debris and native riparian plantings on the regraded bank. A multi-use trail would be incorporated in the riparian area on the riverward edge of the redevelopment. A key consideration with this site concept is whether the existing bridge approach roadways intersecting the site on the northeast side of the river could be modified to allow for a continuous river bank cross-section through those roadway crossings (e.g., rebuild the bridges with abutments further to the east) or if the modified river bank would need to “neck down” at each road crossing to match the existing bank beneath the eastern bridge abutments. Goals and Objectives for Addressing Existing Chinook Salmon Habitat Problems This restoration project would support an overall goal of salmon recovery in WRIA 8, which is to restore habitat for Chinook salmon in the lower Cedar River where much of the historical habitat for this species has been lost due to development along the river and in its floodplain. Specific habitat restoration objectives that this project would address are creation of shallow, low velocity edge habitat and off-channel habitat with overhanging native vegetation that supports juvenile Chinook rearing and refuge, and planting native trees to shade a greater area of the river to reduce water temperatures in the warmer months of the year. Concept Design Description The attached site plan and cross-section sketches show the dimensions and specific features of this restoration project concept. Specific elements of the design include the following: • The wide habitat bench beneath the existing lower trail and retaining wall footprint would be excavated to have a bottom slope of 10H:1V. AGENDA ITEM #1. a) November 2015 Lower Cedar River Chinook Salmon Habitat Restoration Assessment B-18 Habitat Restoration Site Potential and Feasibility Analysis Report • The riverward edge of the new bench would be engaged with river flow all of the time, at shallow depths. The inland portion of the new bench would be engaged with river flow during higher water flood events. • Most of the new bench would be planted with native emergent and shrub species. • The higher elevation areas of the regraded bank would be planted with native trees and shrubs that provide greater shading than existing street landscaping. • Native river rock and alluvium would be placed for the bench substrate. • A multi-use trail would be incorporated in the regraded bank, blending with the upland redevelopment to the northeast. Stakeholder Comments and Other Project Considerations The existing lower trail between Bronson Way North and the Renton Senior Activity Center is for pedestrian use only. Relocating the trail up to North Riverside Drive would likely invite multi-modal use. (Note, the existing upper trail located between Williams Avenue North and the Renton Senior Activity Center is currently multi-modal). There should be sufficient space to accommodate a trail that is 12 feet wide with 2-foot shoulders on each side, which is preferred for multi-use trails. At minimum the trail would need to be 10 feet wide with 2-foot shoulders on each side per the adopted City of Renton Trails and Bicycle Master Plan. Taller tree species and trees with thick branch and canopy characteristics between the new trail and the river are recommended to maximize shade benefits. Such trees would also help to reduce artificial light penetration to the river and the new edge habitat created with this restoration layout. Construction Cost Estimate A construction estimate for this project is attached. AGENDA ITEM #1. a) Engineering Construction Cost Estimate for Conceptual Design Project Name: Cedar River: Site 3 Project Number: 14-05933-000 Client: City of Renton QA Review Completed/Updated By: IBM Last Updated On: 9/24/2015 Approved By: MEApproved On.: 10/12/2015 Item No. WSDOT Std Item No. Spec Section Item Description Qty Sub Item Qty Unit Unit Cost Sub Item Cost Total Cost Div 1 General Requirements 1 Mobilization 1 L.S. 8% 86,070$ 2 Erosion/Water Pollution Control 1 L.S. 5% 53,794$ 3 Utility Relocation 1 L.S. 10% 107,588$ 4 Project Temporary Traffic Control 1 L.S. 5% 53,794$ Div 2 Earthwork5 General Excavation, Incl. Haul 28,800 C.Y. 20$ 576,000$ Div 3 Aggregate Production and Acceptance Div 4 Bases6 Streambed Substrate 900 C.Y. 60$ 54,000$ Div 5 Surface Treatments and Pavements 7 New Trail Through Riparian Area 1,685 L.F. 95$ 160,075$ Div 6 Structures Div 7 Drainage Structures, Storm Sewers, Sanitary Sewers, Water Mains, and Conduits Div 8 Miscellaneous Construction 8 Floodplain LWD 20 Each 1,150$ 23,000$ 9 Riparian Planting 2.36 Acre 30,000$ 70,800$ 10 Work Area Isolation From the River 1600 L.F. 120$ 192,000$ Construction Subtotal 1,377,120$ Surveying 30,000$ Geotechnical Investigations 30,000$ Design 15% 206,568$ Permitting 100,000$ Construction Management 20% 275,424$ Subtotal with Allied Costs 2,019,000$ Contingency 50% 1,009,500$ Tax 9.5% 130,826$ Total (with Contingency and Tax) 3,160,000$ Cost Estimate Template: Herrera APWA O:\proj\Y2014\14-05933-000\Calcs\Cost Estimate\z-obs CostEst_Site3.xlsm Printed On: 10/13/2015 Page 1 of 1 AGENDA ITEM #1. a) JONES PARKC’CN 1st StN Riverside Dr.S Riverside Dr.Williams Ave. N Wells Ave. NPelly Ave. NPark Ave. NBronson Way N43123Excavate to remove trail and retaining wall, create habitat bench on 10:1 slope with large woody debris and native riparian plantings3:1 slope, planted with transitional riparian vegetation Relocated shared use path Upland redevelopment area per City Center Community Plan12 444RM 1.2RM 1.4RM 1.3Remove trail and wall adjacent to river, excavate new bank from river edge to blend with neighborhood redevelopment700 ft405 ft470 ft30 ft (typ)45’ (typ)Cedar RiverNEW CEDAR RIVER TRAILSHARED USE PATH EXISTINGCEDAR RIVER TRAIL115 ft (bank-full width)LEGENDParcel BoundaryRiver MileRMLOWER CEDAR RIVER:SITE 3120012024060FEETAGENDA ITEM #1. a) existing ground surfaceexisting Cedar River Trail16’-0”2’-0”2’-0”1000 cfs500 cfsbank-full dischargeExcavate to remove trail and retaining wall, create habitat bench on 10:1 slope with large woody debris and native riparian plantings N Riverside DrRight-of-Way/ Property Line 11223344Cedar River 8’-0” 3:1 slope, planted with transitional riparian vegetationShared use path with 2’ shoulders on both sidesUpland redevelopment area per City Center Community PlanC’CLOWER CEDAR RIVER:SITE 3505102.5FEETAGENDA ITEM #1. a) Chinook Salmon Habitat Restoration Site No. 4 AGENDA ITEM #1. a) November 2015 Lower Cedar River Chinook Salmon Habitat Restoration Assessment Habitat Restoration Site Potential and Feasibility Analysis Report B-25 Concept Design Narrative for Lower Cedar River Chinook Salmon Habitat Restoration Site No. 4 Project Site Description This site encompasses nearly a half-mile length of the left bank of the river from Houser Way North to Airport Way/Logan Avenue North. The river bank in this area is largely devoid of native overhanging vegetation, and lacks larger trees in many locations that could provide shade to reduce water temperatures in the river during the warmer months of the year. In parts of this site, the river bank is underlain by riprap or other armoring from the original channel construction a century ago. In other parts of this site, the existing bank is lawn underlain by either imported or native soil. The slope of the bank also varies through the length of the site. The habitat restoration work would entail removing or otherwise eradicating invasive vegetation and planting native trees and shrubs using a variety of techniques tailored to site-specific conditions. The variable bank conditions create a challenge for planting techniques that can successfully establish native vegetation. In parts of the site, bioengineered bank stabilization (such as coir-wrapped soil lifts) would be needed to support plantings on the steep bank; in other parts of the site, plants would be installed amidst riprap that lies beneath the ground surface. Goals and Objectives for Addressing Existing Chinook Salmon Habitat Problems This restoration project would support an overall goal of salmon recovery in WRIA 8, which is to restore habitat for Chinook salmon in the lower Cedar River where much of the historical habitat for this species has been lost due to development along the river and in its floodplain. Specific habitat restoration objectives that this project would address are establishing overhanging native vegetation that supports juvenile Chinook rearing and refuge, increasing the number and diversity of native trees that shade the river for reduced water temperatures, and improving instream habitat complexity. Concept Design Description The attached site plan and cross-section sketches show the dimensions and specific features of this restoration project concept. Specific elements of the design include the following: • The restoration work would be confined to areas that are not currently a path, street or sidewalk, with the exception of a low walkway at Jones Park that is subject to frequent inundation during higher flows in the river. This walkway would be removed as part of the project. • All existing trees within the site would be retained unless they are found to be diseased or near the end of their expected life. • Invasive plants would be removed or otherwise eradicated throughout the site using techniques that have been successful in the region and in the Cedar River watershed. AGENDA ITEM #1. a) November 2015 Lower Cedar River Chinook Salmon Habitat Restoration Assessment B-26 Habitat Restoration Site Potential and Feasibility Analysis Report • A palette of native groundcover, shrub and tree species would be used to plant the bank from the toe up to the edge of a path, sidewalk, or wall that defines the western limits of the area that can be planted without displacing existing infrastructure. Stakeholder Comments and Other Project Considerations Care will need to be exercised to minimize root damage to existing trees during invasive plant removal and new tree and shrub planting, and any related soil preparation activities. The downstream end of this site contains a levee that is subject to US Army Corps of Engineers (USACE) vegetation planting and management guidelines, which will need to be addressed in the planting design in coordination between the City and the USACE. It would be highly beneficial to plant trees and shrubs throughout the length of this site to maximize shade and native food source benefits for salmon over time as that vegetation grows, as long as it does not compromise the health of existing trees growing on the bank that are desirable to retain. In-fill tree and shrub plantings would also yield beneficial reduction of artificial light penetration into the river. Businesses, residents, and trail users on this side of the river may object to increased tree and shrub plantings because it would reduce views of the water. Thus, public education regarding the unique opportunity to maximize benefits of revegetation on this bank of the river should be a key component of the project. Construction Cost Estimate A construction estimate for this project is attached. AGENDA ITEM #1. a) Engineering Construction Cost Estimate for Conceptual Design Project Name: Cedar River: Site 4Project Number: 14-05933-000Client: City of Renton QA Review Completed/Updated By: IBM Last Updated On: 9/24/2015 Approved By: ME Approved On.: 10/12/2015 Item No. WSDOT Std Item No. Spec Section Item Description Qty Sub Item Qty Unit Unit Cost Sub Item Cost Total Cost Div 1 General Requirements1 Mobilization 1 L.S. 8% 6,832$ 2 Erosion/Water Pollution Control 1 L.S. 2% 1,708$ 3 Traffic Control (on street and trail) 1 L.S. 10% 8,240$ Div 2 Earthwork 4 Structure Excavation Class B, Incl. Haul 150 C.Y. 20$ 3,000$ 5 Fill and Grading 150 C.Y. 5$ 750$ Div 3 Aggregate Production and Acceptance Div 4 Bases Div 5 Surface Treatments and Pavements Div 6 Structures Div 7 Drainage Structures, Storm Sewers, Sanitary Sewers, Water Mains, and Conduits Div 8 Miscellaneous Construction6 Invasive Vegetation Removal 1.1 Acre 3,000$ 3,300$ 7 Soil Amendment 0.55 Acre 17,000$ 9,350$ 8 Bioengineering Bank Treatment in Some Areas 1 L.S. 20,000$ 20,000$ 9 Riparian Planting 1.1 Acre 40,000$ 44,000$ 10 Irrigation 1 L.S. 5,000$ 5,000.00$ Construction Subtotal 102,180$ Surveying 8,000$ 8,000$ Design 20% 20,436$ Permitting 10% 10,218$ Construction Management 20% 20,436$ Subtotal with Allied Costs 161,300$ Contingency 50% 80,650$ Tax 9.5% 9,707$ Total (with Contingency and Tax) 252,000$ Cost Estimate Template: Herrera APWA O:\proj\Y2014\14-05933-000\Calcs\Cost Estimate\CostEst_Site4.xlsm Printed On: 10/12/2015 Page 1 of 1 AGENDA ITEM #1. a) CEDAR RIVER TRAILCEDAR RIVER TRAILCEDAR RIVER TRAILLiberty ParkCEDAR RIVER TRAILJONES PARKRM 1.2RM 1.4RM 1.3RM 1.1RM 1.5RM 1.6N 1st StN Riverside Dr.S Riverside Dr.Williams Ave. SS. Tobin St.S. Tillicum St.Burnett Ave. SAirport W ay S Wells Ave. S Main Ave. SPark Ave. NBronson Way NHouser Way N(bank-full width)D’D1Dense native riparian vegetation planting on existing bank, adapted to specific bank characteristics that vary111Remove invasive vegetation and plant native riparian vegetation on bank in areas where mature trees do not exist720 ft365 ft680 ft120 ft350 ft115 ft15 ft (varies)Cedar River120 ft (bank-full width)20 ft (var)LEGENDparcel boundaryRiver MileRMLOWER CEDAR RIVER:SITE 4120012024060FEETAGENDA ITEM #1. a) 1000 cfs500 cfs22’-0”8’-0”slope varies along site lengthexisting armored bankbank-full dischargePlant native riparian vegetation on bank while preserving existing mature trees11D’D505102.5FEETLOWER CEDAR RIVER:SITE 4RIGHT OF WAYAGENDA ITEM #1. a) Chinook Salmon Habitat Restoration Site No. 7 AGENDA ITEM #1. a) November 2015 Lower Cedar River Chinook Salmon Habitat Restoration Assessment Habitat Restoration Site Potential and Feasibility Analysis Report B-33 Concept Design Narrative for Lower Cedar River Chinook Salmon Habitat Restoration Site No. 7 Project Site Description This site encompasses approximately 1,100 linear feet of the right bank, on what is currently a privately owned industrial site upstream of Carco Theater. As part of WSDOT’s planned I-405 improvements and as adopted in the 2006 Tri-Park Master Plan, acquisition of the parcel of land on which this site is located is anticipated. This habitat restoration project would modify the river bank along the edge of the planned park improvements. The restoration work would entail excavating the river bank to flatten the grade, allowing for creation of a shallow aquatic habitat bench and a small alcove at the upstream end of the site, each engaged at low to moderate flows in the river; a second habitat bench at slightly higher elevation that is engaged at higher flows in the river; and a gradually sloped bank planted with native riparian vegetation. Large wood structures would be included in various locations within the new habitat area to add habitat complexity, and to prevent high flow velocities from occurring within the shallow edge habitat. Existing retaining walls and other constructed features associated with the historical industrial use of the site in close proximity to the river bank would be removed. Goals and Objectives for Addressing Existing Chinook Salmon Habitat Problems This restoration project would support an overall goal of salmon recovery in WRIA 8, which is to restore habitat for Chinook salmon in the lower Cedar River where much of the historical habitat for this species has been lost due to development along the river and in its floodplain. Specific habitat restoration objectives that this project would address are creation of shallow, low velocity edge habitat and off-channel habitat with overhanging native vegetation that supports juvenile Chinook rearing and flood refuge, increasing habitat complexity with large woody debris that creates and sustains scour pools and provides cover, and planting native trees and shrubs to shade a greater area of the river to reduce water temperatures in the warmer months of the year. Concept Design Description The attached site plan and cross-section sketches show the dimensions and specific features of this restoration project concept. Specific elements of the design include the following: • The aquatic habitat benches would be graded to be nearly flat in cross-section, with native alluvium substrate placed on them. • The bank above the aquatic habitat benches would be graded on a slope of approximately 2H:1V. • A shallow alcove would be created at the upstream end of the aquatic habitat benches. • Most of the new habitat bench areas would be planted with native emergent and shrub species. AGENDA ITEM #1. a) November 2015 Lower Cedar River Chinook Salmon Habitat Restoration Assessment B-34 Habitat Restoration Site Potential and Feasibility Analysis Report • The higher elevation areas of the regraded bank would be planted with native trees and shrubs. • An engineered log structure would be placed at the upstream and downstream ends of the new aquatic habitat benches to slightly deflect high flows to prevent the main stem river channel thalweg from moving into the benched areas, while creating a scour pool for juvenile Chinook salmon cover. • Large woody debris clusters would be placed in several locations on the lower aquatic habitat bench for enhanced habitat complexity and cover, and also to protect the regraded bank from erosion during higher flows. Stakeholder Comments and Other Project Considerations The new park facilities that are planned landward of the habitat restoration area could add artificial light penetration to the river, which is an adverse condition for Chinook salmon. Trees and shrubs planted on the regraded river bank would help to screen artificial light. Restoration project design development should seek to select and locate tree and shrub species that could simultaneously optimize river shading and artificial light screening benefits in relation to proposed locations of new light sources in the park. Construction Cost Estimate A construction estimate for this project is attached. AGENDA ITEM #1. a) Engineering Construction Cost Estimate for Conceptual Design Project Name: Cedar River: Site 7Project Number: 14-05933-000Client: City of Renton QA Review Completed/Updated By: IBM Last Updated On: 9/24/2015 Approved By: ME Approved On.:10/12/2015 Item No. WSDOT Std Item No. Spec Section Item Description Qty Sub Item Qty Unit Unit Cost Sub Item Cost Total Cost Div 1 General Requirements1 Mobilization 1 L.S. 8% 80,072$ 2 Erosion/Water Pollution Control 1 L.S. 5% 50,045$ Div 2 Earthwork3 Clearing and Grubbing 2.5 Acre 16,000$ 40,000$ 4 Structure Excavation Class B, Incl. Haul 1,050 C.Y. 30$ 31,500$ 5 General Excavation, Incl. Haul 14,500 C.Y. 15$ 217,500$ Div 3 Aggregate Production and Acceptance Div 4 Bases 6 Streambed Substrate 490 C.Y. 60$ 29,400$ Div 5 Surface Treatments and Pavements Div 6 Structures Div 7 Drainage Structures, Storm Sewers, Sanitary Sewers, Water Mains, and Conduits Div 8 Miscellaneous Construction7Work Area Isolation From the River (e.g. bulk bags) 1,200 L.F.175$ 210,000$ 8 Large Flow Deflecting Logjam 2 Each 70,900$ 141,800$ 9 Small Flow Deflecting Logjam 3 Each 66,400$ 199,200$ 10 Floodplain LWD 10 Each 1,150$ 11,500$ 11 Riparian Planting 3 Acre 40,000$ 120,000$ Construction Subtotal 1,131,017$ Surveying 15,000$ 15,000$ Design 20%226,203$ Permitting 10%113,102$ Construction Management 20%226,203$ Subtotal with Allied Costs 1,712,000$ Contingency 50%856,000$ Tax 9.5%107,447$ Total (with Contingency and Tax) 2,680,000$ Cost Estimate Template: Herrera APWA O:\proj\Y2014\14-05933-000\Calcs\Cost Estimate\CostEst_Site7.xlsm Printed On: 10/12/2015 Page 1 of 1 AGENDA ITEM #1. a) 7112345672 344 456Shallow aquatic habitat bench w/ riparian vegetation + large woody debris, activated at moderate flows Aquatic/riparian habitat bench w/riparian + transitional vegetation, activated at higher flowsTransitional slope with riparian + upland vegetationSmall flow-deflecting large woody debris structures on habitat benchUpstream flow-deflecting engineered log structureShallow alcoveDownstream flow-deflecting engineered log structureCEDAR RIVER TRAILCEDAR RIVER NATURAL ZONE CEDAR RIVER PARKCEDAR RIVER PARK- PLANNED EXTENSIONRM 2RM 1.8RM 1.9RM 2.1Remove detention ponds, concrete walls and rip-rap adjacent to river; replace with shallow aquatic habitat benchesand riparian plantings integrated with Tri-Park plan redevelopmentF’F90 ft20 ft25 ft25 ft25 ft40 ft960 ft60 ft60 ft100 ft (bank-full width)Cedar RiverLEGENDparcel boundaryRiver MileRMLOWER CEDAR RIVER:SITE 7120012024060FEETAGENDA ITEM #1. a) existing ground surface1000 cfs500 cfsbank- full dischargePlan view note: , , do not show on this section.156712234Shallow aquatic habitat bench w/ riparian vegetation + large woody debris, activated at moderate flows Tri-Park Plan DevelopmentCedar RiverAquatic/riparian habitat bench w/riparian + transitional vegetation, activated at higher flowsTransitional slope with riparian + upland vegetationSmall flow-deflecting large woody debris structures on habitat bench34F F'505102.5FEETLOWER CEDAR RIVER:SITE 7AGENDA ITEM #1. a) Chinook Salmon Habitat Restoration Site No. 10 AGENDA ITEM #1. a) November 2015 Lower Cedar River Chinook Salmon Habitat Restoration Assessment Habitat Restoration Site Potential and Feasibility Analysis Report B-41 Concept Design Narrative for Lower Cedar River Chinook Salmon Habitat Restoration Site No. 10 Project Site Description This site is an existing forested area where a constructed backwater slough channel has been disconnected from the river at lower flow levels. The habitat restoration project would consist of removing riprap at the toe of slopes on both sides of the existing slough channel, excavating an outlet connection to the river that is engaged at all flow levels, excavating an upstream inlet to make it a flow-through side channel with a length of approximately 425 feet, placing large woody debris within the side channel, and planting native riparian vegetation selectively in areas bordering the side channel where the ground is bare and where invasive or nonnative species are present. Goals and Objectives for Addressing Existing Chinook Salmon Habitat Problems This restoration project would support an overall goal of salmon recovery in WRIA 8, which is to restore habitat for Chinook salmon in the lower Cedar River where much of the historical habitat for this species has been lost due to development along the river and in its floodplain. Specific habitat restoration objectives that this project would address are creation of side channel and off-channel habitats with overhanging native vegetation that supports juvenile Chinook rearing and refuge, and increasing habitat complexity with large woody debris that creates and sustains scour pools and provides cover. Concept Design Description The attached site plan and cross-section sketches show the dimensions and specific features of this restoration project concept. Specific elements of the design include the following: • Riprap at the toe of bank on both sides of the existing slough channel would be removed (over a length of approximately 250 feet). • The outlet of the existing slough channel would be excavated lower to match the river bed elevation. • A new upstream inlet connecting the slough channel to the river would be excavated over a length of approximately 125 feet. • Native trees and shrubs removed as part of inlet excavation would be retained onsite to reuse in large woody debris clusters. • An engineered log structure would be placed at the new side channel inlet to deflect a portion of the main stem flow into the side channel at all water levels, while creating a scour pool for juvenile Chinook salmon cover. The scour pool would help to prevent a sill of sediment from depositing at the inlet, enabling flow to enter the side channel at all times. Because this side channel entrance is on the inside of a gentle river bend, this log structure should be relatively large to “invite” flow on the inside of the bend, while not posing risks to recreational users of the river. AGENDA ITEM #1. a) November 2015 Lower Cedar River Chinook Salmon Habitat Restoration Assessment B-42 Habitat Restoration Site Potential and Feasibility Analysis Report • Small logjams would also be constructed at select locations in the side channel to add habitat complexity in the form of scour pools and cover. These could incorporate salvaged vegetation from onsite clearing. • Native alluvium substrate would be placed selectively in the side channel where existing substrate is not desirable. • Native trees and shrubs would be selectively planted in the floodplain surrounding the side channel to complement the existing native plant community, to maximize shading benefits and other ecological functions. Stakeholder Comments and Other Project Considerations No specific comments were received on this design concept. Construction Cost Estimate A construction estimate for this project is attached. AGENDA ITEM #1. a) Engineering Construction Cost Estimate for Conceptual Design Project Name: Cedar River: Site 10Project Number: 14-05933-000Client: City of Renton QA Review Completed/Updated By: IBM Last Updated On: 9/24/2015 Approved By: ME Approved On.:10/12/2015 Item No. WSDOT Std Item No. Spec Section Item Description Qty Sub Item Qty Unit Unit Cost Sub Item Cost Total Cost Div 1 General Requirements1 Mobilization 1 L.S. 8% 12,769$ 2 Erosion/Water Pollution Control 1 L.S. 5% 7,981$ Div 2 Earthwork3 0025 Clearing and Grubbing 0.10 Acre 20,000$ 2,000$ 4 General Excavation, Incl. Haul 1,870 C.Y. 15$ 28,050$ Div 3 Aggregate Production and Acceptance Div 4 Bases 5 Streambed Substrate 120 C.Y. 60$ 7,200$ Div 5 Surface Treatments and Pavements Div 6 Structures Div 7 Drainage Structures, Storm Sewers, Sanitary Sewers, Water Mains, and Conduits Div 8 Miscellaneous Construction6 Remove Existing Riprap 1 L.S. 3,000$ 3,000$ 7 Inlet Control Logjam 1 Each 70,900$ 70,900$ 8 In-Channel LWD Cluster 4 Each 5,140$ 20,560$ 9 Riparian Planting 0.45 Acre 30,000$ 13,500$ 10 Work Area Isolation From the River 120 L.F. 120$ 14,400.00$ Construction Subtotal 180,359$ Surveying 7,500$ 7,500$ Design 25% 45,090$ Permitting 25% 45,090$ Construction Management 20% 36,072$ Subtotal with Allied Costs 314,100$ Contingency 50% 157,050$ Tax 9.5% 17,134$ Total (with Contingency and Tax) 488,000$ Cost Estimate Template: Herrera APWA O:\proj\Y2014\14-05933-000\Calcs\Cost Estimate\CostEst_Site10.xlsm Printed On: 10/12/2015 Page 1 of 1 AGENDA ITEM #1. a) RM 3.3CEDAR RIVER NATURAL ZONECEDAR RIVER NATURAL ZONEMAPLEWOOD GOLF COURSECEDAR RIVER TRAILSE Renton Maple Valley Rd.111222Remove existing rip rap at toe of slopeExcavate inlet and outlet to match existing side-channel cross-section33Flow-through side-channel with large woody debris444Engineered log jam structures for pool creation and inlet control 55555Plant native riparian vegetation adjacent to side channel and selectively in nearby floodplain areas G’GCreate flow-through conditions in existing side channel and enhance aquatic and riparian habitat Cedar River50 ft10 ft110 ft15 ft20 ftLEGENDparcel boundaryRiver MileRMLOWER CEDAR RIVER:SITE 10400408020FEETAGENDA ITEM #1. a) bank- full discharge1000 cfs500 cfsexisting ground surfacePlant native riparian vegetation adjacent to side channel and selectively in nearby floodplain areas 111232354455Remove existing rip-rap at toe of bank Excavate inlet and outlet to match existing side-channel cross sectionFlow-through side channel with large woody debrisEngineered log jam structures for pool creation and inlet control5Cedar Riside-channel G10010205FEETLOWER CEDAR RIVER:SITE 10AGENDA ITEM #1. a) City of Renton Cedar River Maintenance Dredge Project and Lower Cedar River Restoration Assessment 1 Utilities Committee Meeting February 1, 2016 1 AGENDA ITEM #2. a) City of Renton CEDAR RIVER MAINTENANCE DREDGE PROJECT 2 2 Utilities Committee Meeting February 1, 2016 AGENDA ITEM #2. a) 3 AGENDA ITEM #2. a) Project Description Continuation of 1998 permitted project Maintenance for existing Lower Cedar River Section 205 Flood Hazard Reduction Project 4 Photo: 1990 Cedar River flood City of Renton CEDAR RIVER MAINTENANCE DREDGE PROJECT AGENDA ITEM #2. a) 5 Project Description •Planned 4 ft. average dredge depth •Planned gradual slope from N. Boeing Bridge to Logan •Steeper transition reach from Logan to Williams Dredging Bank stabilization, maintenance and repair New armoring AGENDA ITEM #2. a) Dredging Extents A 6 Wetlands Wetlands Wetlands Wetlands The dredge width will be variable to match channel variations along the length of the project, It is anticipated that the dredge prism will be trapezoidal downstream of South Boeing Bridge and a complex variation of the trapezoidal section upstream of the bridge. AGENDA ITEM #2. a) 7 Project Mitigation Removal and control if invasive plans species Vegetation plantings Filling void spaces in riprap bank protection Lower reach gabion bank protection removal Spawning channel maintenance and monitoring Lighting impact reduction along dredging reach Wetland mitigation bank credits AGENDA ITEM #2. a) Project Status & Schedule •Permit Application (JARPA) submitted (2/10/14) •Joint Public Notice issued (7/8/14 to 8/8/14) •BA sent to NOAA Fisheries on 2/13/2015 •Meeting with USACE on May 1st 2015 •Project coordination meeting with USACE, WDFW, Ecology and Muckleshoot Indian Tribe on 8/19/2015. •Submitted to the agencies a revised mitigation plan on 10/15/15 •Draft mitigation agreement Working towards obtaining HPA and Army Corps of Engineers 404 Permit •Design team reviewing plans and providing comments Working towards finalizing Project 90% design •Summer of 2016 (June 15 – August 31) Construction 8 AGENDA ITEM #2. a) Project Funding King County Flood Control District King County Flood Control District Sub-Regional Opportunity Fund (Renton’s share) 9 AGENDA ITEM #2. a) City of Renton 10 Utilities Committee Meeting February 1, 2016 AGENDA ITEM #2. a) •Project funded by a $150,000 grant from the Washington State Puget Sound Acquisition and Restoration (PSAR) Program •The grant requires the City of Renton to: •conduct thorough evaluation of potential Chinook salmon habitat restoration sites and develop concept designs for up to 6 of them •THANKS TO RCO & WRIA 8 Project Description 11 AGENDA ITEM #2. a) Project Area Approx 3.5 miles from Logan Avenue N. to Maplewood Golf Course 12 AGENDA ITEM #2. a) 14 Candidate Sites Identified Wide variety of site sizes, settings, and restoration approaches 13 AGENDA ITEM #2. a) Flood risk reduction benefit? Effects on existing parks Effects on trails, golf course, and on-river recreational uses Constructability Permitting complexity Funding potential Land rights Maintenance requirements Potential to bundle with another restoration site(s) •Distinct education value •Ability to package with other planned project at site •Consistency with adopted plans •Damaging to existing functional habitat (negative) Other unique attributes: Multi-objective Evaluation Criteria 14 AGENDA ITEM #2. a) Candidate Site Evaluation Results •Individual site scores ranged from 16 to 34 •Conceptual designs prepared for top six ranked sites •4 sites downstream of I-405 •2 sites further upriver 15 AGENDA ITEM #2. a) Overview of 6 Conceptual Designs 16 AGENDA ITEM #2. a) Site 1: Senior Activity Center – create alcove in lawn area 17 AGENDA ITEM #2. a) Site 2: Cedar River Trail From Bronson Way N. to Senior Activity Center – create habitat bench in trail footprint 18 AGENDA ITEM #2. a) Site 2 – cross section •Remove trail paving and rock gabions supporting it •Preserve existing retaining wall between trail and N. Riverside Dr. •Relocate trail use to N. Riverside Dr., which would require converting to one lane of vehicle traffic 19 AGENDA ITEM #2. a) Site 3 – Major River Bank/Riparian Area Modification from Bronson Way N. to Senior Activity Center w/ Redevelopment Plan 20 AGENDA ITEM #2. a) Much larger scale modification than Site #2 Site 3 – cross section 21 AGENDA ITEM #2. a) Site 4 – Riparian Planting on South River Bank from Houser Way N. to Logan Avenue N. Selectively plant native shrubs and trees on river bank without altering trail or street 22 AGENDA ITEM #2. a) Site 4 – cross section Varying methods of planting on existing bank: •Some areas in soft soil, some underlain by riprap •Some areas steeper than others •Remove invasive vegetation •Preserve mature trees •Seek to maximize shading of river and screening artificial light penetration to river 23 AGENDA ITEM #2. a) Site 7 – River Bank Modification in Planned Cedar River Park Expansion Area 24 AGENDA ITEM #2. a) Site 7 – cross section 25 AGENDA ITEM #2. a) Site 10 – Side Channel Improvements in Forested Area Just Downstream of Sockeye Spawning Channel Outlet Connect side channel to river at both ends and enhance habitat throughout extended length 26 AGENDA ITEM #2. a) Site 10 – cross section 27 AGENDA ITEM #2. a) Questions 28 AGENDA ITEM #2. a) REGULAR COUNCIL - 07 Dec 2015 SUBJECT/TITLE:Establishment of the SE 165th Street Sanitary Sewer Extension Special Assessment District No. 0048 RECOMMENDED ACTION:Refer to Utilities Committee DEPARTMENT:Utility Systems Division STAFF CONTACT:Mike Benoit, Civil Engineer EXT.:7206 FISCAL IMPACT: Expenditure Required:$ N/A Transfer Amendment:$ N/A Amount Budgeted:$ N/A Revenue Generated:$ N/A Total Project Budget:$ N/A City Share Total Project:$ N/A SUMMARY OF ACTION: The Wastewater Utility has completed construction of the SE 165th Street Sanitary Sewer Extension. At the regular Council meeting on April 27, 2015 Council approved the preliminary Special Assessment District. The final costs and assessments have been determined and the property owners will be notified as directed by City Ordinance No. 4444. There are 11 potential single-family units within the Special Assessment District. The per-unit assessment for the district is $13,000. Per City Code, interest will accrue on the potential assessment at a rate of 0.77% for a period of 10 years beginning 30 days after final approval of the ordinance. EXHIBITS: A.Issue Paper B.Draft Final Notice of Potential Assessment C. Final Assessment District Roll D. Draft Ordinance STAFF RECOMMENDATION: Approve the final SE 165th Street Sanitary Sewer Extension Special Assessment District No. 0048 and present the Ordinance for first reading. AGENDA ITEM #3. a) PUBLIC WORKS DEPARTMENT M E M O R A N D U M DATE: November 19, 2015 TO: Ed Prince, Council President Members of the Renton City Council VIA: Denis Law, Mayor FROM: Gregg Zimmerman, Administrator STAFF CONTACT: Michael Benoit, Wastewater Utility, ext. 7206 SUBJECT: Establishment of the SE 165th Street Sanitary Sewer Extension Special Assessment District No. 0048 ISSUE: Does the City wish to finalize the Special Assessment District for the SE 165th Street Sanitary Sewer Extension Project in order to ensure that the cost of the project is equitably distributed to those who benefit? RECOMMENDATION: Approve the final SE 165th Street Sanitary Sewer Extension Special Assessment District No. 0048 and present the Ordinance for first reading. BACKGROUND SUMMARY: The City has completed work on the SE 165th Street Sanitary Sewer Extension Project. This project installed sanitary sewer in SE 165th Street (aka South 28th Street) between 106th Place SE (aka High Avenue South) and 108th Avenue SE (aka Jones Avenue South). This project provides direct sanitary sewer service to properties adjacent to the new sewer main (map attached). The Wastewater Utility proposes to use a per-connection method of calculating the assessments for the properties within the proposed assessment district. This method takes the size of the existing parcels and anticipates how many single-family equivalent residences could be constructed in accordance with the City’s proposed zoning for the area. There are 11 potential lots within the proposed assessment district boundary. AGENDA ITEM #3. a) Mr. Ed Prince, Council President Page 2 of 2 November 19, 2015 C:\Users\Mgregor\Downloads\A. Issue Paper (1).Doc\MABad The final cost for the project is $143,350, which includes construction, staff cost and survey. The Wastewater Utility is proposing to divide the cost of the project by the number of potential lots that can gain direct benefit to calculate the per-connection charge for the sewer special assessment district. The project cost used to calculate the preliminary assessment was $143,000, which calculated to a per-connection charge of $13,000. Because the final cost is insignificantly higher than the preliminary estimate ($143,350 vs $143,000), we are recommending that we use the preliminary per-connection charge of $13,000. Per City Code, interest will accrue on the potential assessment at a rate of 0.77% for a period of 10 years beginning 30 days after final approval of the ordinance. CONCLUSION: It has been the policy of the City that when sanitary sewer facilities have been installed that the City hold a Special Assessment District in order to ensure each property that benefits from the new facility pays its fair share of the costs. This policy helps ensure the existing ratepayers do not pay a disproportionate share of the costs for these City-installed facilities. Therefore, we recommend that Council approve staff’s recommendation for the establishment of the SE 165th Street Sewer Extension Special Assessment District No. 0048. Attachment cc: Lys Hornsby, Utility Systems Director Dave Christensen, Wastewater Engineering Manager AGENDA ITEM #3. a) AGENDA ITEM #3. a) :u..__. w..ur__‘Ltu E,.._,..___1.:. m....__m-,._._..r%.,..m:.!..§..,Fy _._#A1¢. .i3_:u.»1.1..x\x_.y1__?v.:|T._....=.4:;x< IFI!.r_. \_r|..:E _ 1..1.!,..5_June. _ x 2:.x_:._.3.q._._ 2F.:4._=_ 15..._ P5..L....,.Jr.._._..;.J..u=..__wx.._. 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