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HomeMy WebLinkAboutRS_CedarRiverShorelineStabilization_181030_v1.pdf Golder Associates Inc. 18300 NE Union Hill Road, Suite 200, Redmond, Washington, USA 98052 T: +1 425 883-0777 F: +1 425 882-5498 Golder and the G logo are trademarks of Golder Associates Corporation golder.com SRM Development (SRM) requested that Golder Associates Inc. (Golder) review available information related to existing shoreline stabilization at a proposed site called the Cedar River Apartments Project (Project). The King County assessor Parcel Number for the Project is 1723059026, which is generally located along the Maple Valley highway just upstream of the intersection of Interstate 405 and the Cedar River in Renton, Washington. Our review was limited to available studies and applicable technical documents and focused on confirming whether bank stabilization is necessary at the site. In addition, Golder is providing preliminary input on the feasibility of implementing bank stabilization as addressed in the Renton Municipal Code (Code) within the context of the hierarchal alternatives process. No new technical assessments or investigations were completed as a part of this work. Our scope includes the review as described above, a brief site visit (completed on September 4, 2018), and development of this technical memorandum summarizing the initial conclusions and results. 1.0 BACKGROUND INFORMATION We reviewed and/or considered the following information:  Project Site Plan, by RMA (Appendix A);  Project 100-year Flood Boundary delineation, by SRM (Appendix B);  “Cedar River Channel Migration Study”, King County Water and Land Resources Division, Department of Natural Resources and Parks, lead author Terry Butler (now retired), dated April 2015 (available on-line at: https://your.kingcounty.gov/dnrp/library/water-and-land/flooding/mapping/Cedar- CMZ/Cedar_CMZ_study_&maps_April_2015.pdf);  Phone conversation with Jeanne Stypula, Managing Engineer (new contact for the Cedar River channel migration study), King County River and Floodplain Management Section;  Historical documentation from Gary Merlino Construction Company (GMCC), the most recent batch plant operator at the site, whereby the focus was on the historical site operations going back to the original site operator, Stoneway Gravel Company;  Renton Municipal Code, 4-3-090 Shoreline Master Program Regulations, outlined in email from S. Sandstrom to A. Kammereck dated October 3, 2018 (Appendix C); TECHNICAL MEMORANDUM DATE 10/30/2018 Project No. 18101829 TO Andy Loos SRM Development CC Sarah Sandstrom, The Watershed Company FROM Andreas Kammereck, PE; Joe Mitzel, EIT EMAIL akammereck@golder.com, jmitzel@golder.com REVIEW OF SHORELINE STABILIZATION ALTERNATIVES FOR THE CEDAR RIVER APARTMENTS PROJECT, IN RENTON, WA Andy Loos Project No. 18101829 SRM Development 10/30/2018 2  “Summary of Integrated Streambank Protection Guidelines”; abbreviated summary of the Integrated Streambank Stabilization Protection Guidelines (ISPG) technical document developed by the Washington State Department of Fish and Wildlife (WDFW) by lead authors Cramer, Bates, and Miller (Appendix D);  Project Shoreline Buffer Diagrammatic and Court Concept Plan, by SRM (Appendix E); and,  Example stream and river habitat restoration, enhancement, and bank stabilization projects (Appendix F). 2.0 SITE VISIT OBSERVATIONS A brief site visit was completed on September 4, 2018 to observe and review riverine, fluvial geomorphic, and floodplain conditions relative to the Project. The ground elevations throughout the parcel are generally flat and elevated above the river active channel, generally matching the top of an existing concrete retaining wall that runs along the rightbank (orientation looking downstream) edge of the main channel. The concrete retaining wall is approximately 15-20 feet in height, with a vertical face extending from the general parcel ground elevation down to river level. Figure 2-1: View looking upstream (Left) and downstream (Right) along rightbank of the Cedar River where it abuts the existing concrete retaining wall The 100-year flood inundation limits (Appendix B) generally correspond with the right-bank side of the main active channel where it runs along the concrete retaining wall on the upstream end of the project (the actual elevation is likely somewhere along the face of the wall), and reaches further into the Project in the area around the settling ponds (intersecting ground elevation where the site slopes away from the river and located approximately mid- point along the river bank at the existing concrete bays). It then moves back towards the river and follows the rightbank side of the main channel through the downstream end of the Project (elevation along the sloping bank). Based on experience with similar projects, we assume the Ordinary High Water Mark (OHWM) follows closely with the rightbank side of the main channel (and along the near vertical wall face). Andy Loos Project No. 18101829 SRM Development 10/30/2018 3 3.0 KING COUNTY CMZ STUDY Review of the King County (2015) study of channel migration hazards along the Cedar river show the site is located within an unconstrained channel migration zone (Figure 3-1) and define the channel migration zone regulatory status covering much of the parcel as a “severe hazard area” (Figure 3-2). The unconstrained channel migration zone does not account for the existing concrete retaining wall that runs along the rightbank side of the channel through the parcel, which is standard of practice this these types of assessments; the term “unconstrained” refers to the expected limits of the channel migration if no structure were there to impede the river. Figure 3-1: Unconstrained Channel Migration Map (Map 6, Panel 1 of 8) Figure 3-2: Channel Migration Zone (Map 7, Panel 1 of 8) The technical methods and approach for King County (2015) study were discussed briefly with Jeanne Stypula, Managing Engineer in the King County River and Floodplain Management Section, who is the current point of contact for the study because the lead author for the study has retired from the County. The approach and methods used for the study represent the standard of practice for these type of assessments, and based on our Andy Loos Project No. 18101829 SRM Development 10/30/2018 4 review of the document and discussions with King County we do not envision that additional technical studies would result in new or changed conclusions on the delineation of channel migration hazards for the site. 4.0 HISTORICAL SITE CONDITIONS Historical information from the Gary Merlino Construction Company (GMCC), who was the most recent batch- plant operator at the site, provides a summary of historical site conditions and changes in land use going back decades for the Project site. The site was originally developed in the early 1930’s by the Stoneway Dock Company with a concrete batch plant and rock crushing operation. The sand and gravel for the concrete batch plant was dredged from the river. Figure 4-1 shows an aerial photo from the site in 1946. Note how the main river channel reaches into the middle of the site in the area where the settling ponds (i.e. old concrete bays) currently exist. Additionally, the active channel appears to be unconfined with no apparent in-channel control structures. There appears to be gravel mining activities in the upstream portion of the site, presumably to support the batch plant operations. Figure 4-1: 1946 Aerial Photo A newspaper clipping from 1954 shows an oblique view looking downstream of the site. The batch plant sits predominately in the middle of the site and the central portion of the site has been filled and flattened. There is evidence of a storage pond along the river edge toward the upstream end of the site. Around this time the operating company name changed to the ‘Stoneway Sand and Gravel Company’. Andy Loos Project No. 18101829 SRM Development 10/30/2018 5 Figure 4-2: Newspaper Clipping from 1954 Figure 4-3 provides an oblique aerial view from 1961, while Figure 4-4 shows a plan view aerial photo from 1962. At this time, the river channel ran close to the settling pond (reference photos) towards the upstream end of the site. Comparison of the 1962 and 1977 aerial photos shows that site operations have pushed the river channel to the south, presumably to expand the site area. Similarly, the historical channel alignment appears to have been filled at the upstream end of the site for expansion of operations. While a long linear bank alignment through the upstream end of the site is evident in the 1961 photo (Figure 4-3), there appears to be changes in the bank Andy Loos Project No. 18101829 SRM Development 10/30/2018 6 alignment even in the 1962 aerial photo (Figure 4-4); this may be explained by the photos showing different flow conditions (i.e. 1962 may show lower flows that expose gravel bars along the rightbank side of the channel). No retaining wall is evident in 1977 aerial photo (Figure 4-5). Figure 4-3: Oblique Aerial Photo from 1961 Figure 4-4: Aerial Photo from 1962 Andy Loos Project No. 18101829 SRM Development 10/30/2018 7 Figure 4-5: Aerial Photo from 1977 Figure 4-6: Aerial Photo from 1985 Andy Loos Project No. 18101829 SRM Development 10/30/2018 8 Figure 4-7: Aerial Photo from 2002 Figure 4-8: Google Aerial Image from 2018 The 1985 aerial photo (Figure 4-6) shows a similar rightbank river bank alignment as the 1977 photo (Figure 4-5), and no retaining wall is evident. By the 2002 (aerial photo Figure 4-7), the retaining wall is evident as a pronounced line defining the rightbank side of the main river channel. Concrete mixer trucks are easily identified Andy Loos Project No. 18101829 SRM Development 10/30/2018 9 parked along the edge of the retaining wall (Figure 4-7). The bank line from 2002 appears unchanged with the current bank line (Figure 4-8) seen in a Google Image from 2018. 5.0 RENTON MUNICIPAL CODE SRM requested Golder look at the Renton Municipal Code (Code) with respect to bank stabilization for existing structures (see Appendix C for highlighted Code sections for review). The Code outlines the need for repairing or retaining bank stabilization and provides a process for prioritizing bank stabilization methods called the “Shoreline Stabilization Alternatives Hierarchy”. From 4-3-090F.4.c.iii.a; the Code requires a demonstrated need by “geotechnical analysis” to protect “principal uses or structures from erosion…”. Based on review of available information and the results of the King County (2015) study, there is a demonstrated need to protect against future erosion and scour that could threaten the Project. From 4-3-090F.4.a.iii.a.b.c.d.e; the Code outlines the “Shoreline Stabilization Alternatives Hierarchy”, which says that structural stabilization measures should only be used when more natural, flexible, non-structural methods such as vegetative stabilization and bio-engineered methods are not feasible. The alternative types and methods of stabilization are defined in order of priority by the following hierarchy of preference (whereby (a) represents increased priority): (a) No Action (allow the shoreline to retreat naturally), increase building setbacks and relocate structures; (b) Flexible defense works constructed of natural materials including measures such as soft shore protection, bioengineering, including beach nourishment, protective berms, or vegetative stabilization; (c) Flexible defense works, as described above, with rigid works, as described below, constructed as protective measure at the buffer line; (d) A combination of rigid works, as described below, and flexible defense works, as described above; and, (e) Rigid works constructed of artificial materials such as riprap or concrete. The Code does not provide detailed guidance on the definition of “soft shore protection”, “bioengineering”, or “vegetative stabilization”; based on previous project experience, we assume these references imply using bank stabilization methods addressed and explained in state-of-the-practice guidance documents developed by the Washington State Department of Fish and Wildlife (WDFW), such as the “Stream Habitat Restoration Guidelines” (SHRG), dated April 2012, and available at: https://wdfw.wa.gov/publications/01374/ ); and “Integrated Streambank Protection Guidelines” (ISPG) developed in 2002, and available at: https://wdfw.wa.gov/publications/00046/. An abbreviated summary of the ISPG (2002) developed by the primary authors (Cramer, Gates, and Miller) is included in Appendix D and highlights the key components of current stream bank stabilization methods and approaches with “selection and design of stream bank protection techniques that protect or restore aquatic and riparian habitats” (Appendix D). The ISPG (2002) reflects the current trend and guiding principles of stream bank stabilization work that need to be incorporated into any project planning and design effort, as follows (Appendix D): Andy Loos Project No. 18101829 SRM Development 10/30/2018 10 • Erosion is a natural process that is essential to ecological health; • Erosion is often exacerbated or caused by human activities; • Causes of erosion (not just symptoms) must be solved when appropriate; • Basin, reach, and meander belt management are essential to integrated streambank projects; • Habitat protection must be assimilated into streambank projects; • Mitigation sequencing must be integrated into streambank projects; and, • Impacts to natural channel processes must be mitigated. These guiding principles should be incorporated into project planning, design, permitting, and construction of stream stabilization projects. 5.1 Feasibility of Hierarchal Alternatives We understand the conceptual plan for the buffer zone along river bank is represented in the “Project Shoreline Buffer Diagrammatic and Court Concept Plan” (Appendix E). In general, with regard to references in the hierarchical alternatives process, we assume the reference to “flexible defense works” is consistent with the standard-of-practice technical resources as described in ISPG (2002) and SHRG (2012) for “biotechnical bank protection techniques” such as (but not limited to): woody plantings, herbaceous cover, soil reinforcement, riparian buffers, coir and straw logs, bank reshaping, and buffer management. Similarly, “structural bank protection techniques” refer to (but are not limited to): anchor points, roughness trees, large woody debris (LWD) riprap, log toe, rock toe, crib walls, ballast, and manufactured retention systems. Additional measures such as “In-stream flow redirection techniques” that could be used, that include (but are not limited to): groins, buried groins, barbs, engineered debris jams (i.e. engineered log jams, a.k.a. ELJ’s), drop structures, and porous weirs. Our initial review of these types of streambank protection measures relative to the Project and relative to the hierarchical alternatives process finds the “No Action’ alternative is not feasible because it leaves no measures to protect the Project area from future bank erosion, scour, and channel migration hazards. The “Flexible Defense Works” alternative is not likely sufficient (and thereby not feasible) to establish a level of protection commensurate with the proposed Project development, primarily because “soft” vegetative measures assume that changes can and will occur over the long-term. The currently provided buffer zone of 100 feet is likely not enough to provide the required offset for natural processes to occur while maintaining sufficient offset from the developed portion of the site. The “Flexible Defense Works with Rigid Defense Works constructed at the Buffer Line” is not likely feasible because it would take more room than is available, i.e. there is little or no space to build streambank protection measures landward of the buffer line, which is 100 feet offset from the river bank. The “Combination of Rigid and Flexible Works” appears feasible and could provide the required level of protection. This alternative would likely require much of the 100 foot buffer space to construct. This alternative would likely include a combination of biotechnical and structural bank protection techniques as described above. These techniques would need to be designed and constructed to meet current regulatory level-of-protection requirements, which is typically the 100-year flood level of protection but may vary depending on the intent and function of each component of the overall project and the level of corresponding risk. The work would likely entail combining grading the bank area within the buffer to have a variable sloped and vegetated topography consistent with typical floodplain regimes, LWD configured in single or multiple pieces, ELJ’s to replicate the function of natural LWD and provide erosion and scour protection, riprap rock materials in targeted areas (mostly in bank tow Andy Loos Project No. 18101829 SRM Development 10/30/2018 11 areas), piles (steel and/or wood) to secure LWD and ELJ’s, and other structural components, or variations thereof, needed to restore and enhance habitat and provide bank protection mitigation for expected erosion and scour conditions. Examples of similar projects that include a combination of techniques are included in Appendix F. These examples are presented to demonstrate there is a range of relevant applications that have been successfully constructed in Pacific Northwest riverine systems. Please note there are numerous other project examples out there that are applicable and would inform continued planning and discussion, and additional planning and design would be needed to develop options that best fit the Project requirements. The “Rigid works” alternative appears feasible, but has the lowest preference in the hierarchy of alternatives when other alternatives (as described above) are feasible. 5.1.1 Relative Planning Level Costs Costs should be included in feasibility review of bank stabilization alternatives for the site. Relative ranges of costs for targeted streambank stabilization techniques are included in Table 5-1. Note, these costs are intended for planning purposes only, to provide a relative order-of-magnitude understanding of costs. They represent low and high unit costs from ISPG (2002) which have not been adjusted to current values. More detailed and comprehensive costing assessments are needed to develop costs that are representative of Project site-specific proposed stabilization measures. Costs in Table 5-1 were developed assuming a project length of approximately 1,500 feet or approximately 0.30 mile (i.e. the approximate Project length of the bank along the rightbank side of the main channel), and consider only materials and construction costs. Design costs including geologic assessments, geotechnical engineering and investigations, hydrotechnical (i.e. hydrologic, hydraulic, and fluvial geomorphic) engineering, and civil design and survey costs are not addressed. Integrated Streambank Protection Guidelines Techniques (2002) Description Estimated Cost (Low to High) Biotechnical bank protection techniques woody plantings, herbaceous cover, sol reinforcement, riparian buffers, coir and straw logs, bank reshaping, and buffer management ~$40,000 to ~$200,000 Structural bank protection techniques anchor points, roughness trees, riprap, log toe, rock toe, crib walls, ballast, and manufactured retention systems ~$100,000 to ~$200,000 In-stream flow (i.e. in the bed or bank) redirection techniques groins, buried groins, barbs, engineered debris jams (i.e. LWD and ELJ’s), drop structures, and porous weirs ~$200,000 to ~$2,000,000 Table 5-1: Relative Streambank Stabilization Technique Costs Based on our experience from similar and recently completed project work, the ranges of estimated costs in Table 5-1 are likely low. Note also that some combination of biotechnical, structural, and in-stream structures may be needed for restoration and stabilization at the Project site, so total costs could be the combination of costs for respective techniques. Andy Loos Project No. 18101829 SRM Development 10/30/2018 12 Refer to Table 5-2 for a listing of comparable example streambank restoration and stabilization projects and corresponding total project costs (note year of completion for adjusting costs to current value). Additional information about the projects can be found in Appendix F, including some photographs, project location, and a link to additional publicly available project details. The example project costs range from approximately $600,000 to $10,000,000, which represents the likely range of work that would be required at the Project site for habitat enhancement, restoration, and bank stabilization. Project Cost Year Notes Upper Washougal River $800,000 2011 60 ft logs, 160 logs installed in 2011 to restore riverine function, spread over 5 mile reach NF Stillaguamish $621,384 2008-2012 7 structures, 0.25 miles of streambank stabilized and habitat restoration, 0.25 mile reach Saxon Reach $1,180,247 2010-2013 7 structures, 0.12 miles of streambank stabilized and habitat restoration, 0.12 mi length Riverberry-Davis VanDellen $1,200,000 ~1995 18 structures, 0.60 miles of river bank stabilized Hoh River Bank Stabilization $7,000,000 2004 4 mid-channel ELJs, 6 bank ELJs, and 2 ELJs for highway embankment stabilization, over 0.25 mile reach Lower Germany Creek Restoration not available 2011-2012 habitat restoration, river bank stabilization Mashel Eatonville Restoration $1,254,992 2009-2012 21 structures, 0.12 miles of streambank stabilized SR 20 Skagit River $10,200,000 2014 ~1,700 dolos with LWD and ELJ's along 0.26 mile bank, river bank stabilization along highway Table 5-2: Example Stabilization Projects The above summarized costs provide a relative understanding for how particular measures compare. As previously mentioned, a more comprehensive and detailed cost assessment would be needed to better define costs for proposed site-specific measures. 5.1.2 Assessing Risk All streambank stabilization projects have inherent risk, corresponding to the dynamics and uncertainties that come with working in the riverine environment. Identifying, assessing, and managing those risks in the planning, design, permitting, construction, and monitoring of streambank stabilization projects is therefore critical. Any risk assessment for this Project should consider the following (but not limited to): the regulatory setting, costs, land use, the likelihood of continued bank erosion and channel migration potential at the site, the feasibility and function of proposed streambank stabilization measures, long-term performance of installed measures, monitoring, operational requirements, riverine and riparian habitat, and public safety. 6.0 CONCLUSIONS Review of the channel migration assessment completed by King County (2015) indicates that much of the Project site is located within a channel migration zone. The King County (2015) study approach does not account for the existing retaining wall, which meets the standard of practice for these types of assessments. We do not see additional studies changing the fundamental conclusions of the County’s study. Assessing risk in terms of bank stabilization alternatives and feasibility and costs needs to be incorporated into the planning, design, permitting, construction, and monitoring elements of the Project. Andy Loos Project No. 18101829 SRM Development 10/30/2018 13 From a geotechnical and hydrotechnical engineering, geologic, long-term performance, and risk management perspective, the “Combination of Rigid and Flexible Works” alternative appears feasible and would likely require much of the 100 foot buffer space for construction. This alternative could likely be constructed landward of the OHWM. Proposed streambank stabilization measures should incorporate principles and approaches as outlined in SHRG (2012) and ISPG (2002), or similar applicable technical resources. A range of potential costs are presented herein. More detailed planning, investigation, design, and cost estimate are needed to develop a site- specific bank stabilization package. 7.0 CLOSING Please contact the undersigned if there are any questions or comments, or if further clarification or additional information is needed. Joe MItzel, EIT Andreas Kammereck, PE Engineer Principal Engineer JM/AQK/aqk d:\new_aqk_working\projects\temp_watershed company_cedar river\final_srm_cedar river cmz review_10302018.docx Andy Loos Project No. 18101829 SRM Development 10/30/2018 14 Appendix A Andy Loos Project No. 18101829 SRM Development 10/30/2018 15 Appendix B CEDAR 5,9(5100-YR FLOOD BOUNDARYNOTES1. 1% CHANCE ANNUAL FLOODDEMARCATED USING FEDERALEMERGENCY MANAGEMENTAGENCY FLOOD PROFILES FORTHE CEDAR RIVER.1% CHANCE ANNUALFLOOD BOUNDARY200'50'25'0100' Andy Loos Project No. 18101829 SRM Development 10/30/2018 16 Appendix C From:Sarah Sandstrom To:Kammereck, Andreas Subject:Renton Code sections Date:Wednesday, October 3, 2018 10:37:29 AM Attachments:image002.png SRM Renton_Site_Shorline Diagrammatic_2018-09-11.pdf Hi Andreas, I am copying the code section we discussed below with highlights on the applicable sections. I have also attached the diagrammatic sketch of the shoreline buffer restoration. Let me know if you have any questions. Thanks, Sarah 4-3-090D General Development Standards F. Shoreline Modification 4. Shoreline Stabilization a. General Criteria for New or Expanded Shoreline Stabilization Structures: i. Avoidance of Need for Stabilization: The need for future shoreline stabilization should be avoided to the extent feasible for new development. New development on steep slopes or bluffs shall be set back sufficiently to ensure that shoreline stabilization is unlikely to be necessary during the life of the structure, as demonstrated by a geotechnical analysis. ii. Significant Impact to Other Properties Prohibited: The need for shoreline stabilization shall be considered in the determination of whether to approve new water-dependent uses. Development of new water-dependent uses that would require shoreline stabilization which causes significant impacts to adjacent or down-current properties and shoreline areas should not be allowed. iii. Shoreline Stabilization Alternatives Hierarchy: Structural shoreline stabilization measures should be used only when more natural, flexible, nonstructural methods such as vegetative stabilization, beach nourishment and bioengineering have been determined infeasible. Alternatives for shoreline stabilization should be based on the following hierarchy of preference: (a) No action (allow the shoreline to retreat naturally), increase building setbacks, and relocate structures. (b) Flexible defense works constructed of natural materials including measures such as soft shore protection, bioengineering, including beach nourishment, protective berms, or vegetative stabilization. (c) Flexible defense works, as described above, with rigid works, as described below, constructed as a protective measure at the buffer line. (d) A combination of rigid works, as described below, and flexible defense works, as described above. (e) Rigid works constructed of artificial materials such as riprap or concrete. iv. Limited New Shoreline Stabilization Allowed: New structural stabilization measures shall not be allowed except when necessity is demonstrated in one of the following situations: (a) To protect existing primary structures: (1) New or enlarged structural shoreline stabilization measures for an existing primary structure, including residences, should not be allowed unless there is conclusive evidence, documented by a geotechnical analysis, that the structure is in danger from shoreline erosion caused by currents, or waves within three (3) years, or where waiting until the need is immediate would prevent the opportunity to use measures that avoid impacts on ecological functions. Normal sloughing, erosion of steep bluffs, or shoreline erosion itself, without a scientific or geotechnical analysis, is not demonstration of need. The geotechnical analysis should evaluate on-site drainage issues and address drainage problems away from the shoreline edge before considering structural shoreline stabilization if on-site drainage is a cause of shoreline instability at the site in question. (2) The shoreline stabilization is evaluated by the hierarchy in subsection F4aiii of this Section. (3) The shoreline stabilization structure will not result in a net loss of shoreline ecological functions. (4) Measures to reduce shoreline erosion in a channel migration zone (CMZ) require a geomorphic assessment by a Washington-licensed geologist with engineering geology or hydrogeology specialty license plus experience in conducting fluvial geomorphic assessments. Erosion control measures are only allowed if it is demonstrated that: the erosion rate exceeds that which would normally occur in a natural condition; the measure does not interfere with fluvial hydrological and geomorphologic processes normally acting in natural conditions; and the measure includes appropriate mitigation of impacts to ecological functions associated with the stream. (b) New Development: In support of new development when all six (6) of the conditions listed below apply and are documented by a geotechnical analysis: (1) The erosion is not being caused by upland conditions, such as the loss of vegetation and drainage. (2) Nonstructural measures, such as placing the development further from the shoreline, planting vegetation, or installing on-site drainage improvements, are not feasible or not sufficient. (3) The need to protect primary structures from damage due to erosion is demonstrated through a geotechnical report. The damage must be caused by natural processes, such as currents and waves. (4) The shoreline stabilization structure is evaluated by the hierarchy in subsection F4aiii of this Section. (5) The shoreline stabilization structure together with any compensatory mitigation proposed by the applicant and/or required by regulatory agencies is not expected to result in a net loss of shoreline ecological functions. (6) The proposed new development is not located in a channel migration zone (CMZ). (c) Restoration and Remediation Projects: To protect projects for the restoration of ecological functions or hazardous substance remediation projects pursuant to chapter 70.105D RCW when both of the conditions below apply and are documented by a geotechnical analysis: (1) The shoreline stabilization structure together with any compensatory mitigation proposed by the applicant and/or required by regulatory agencies is not expected to result in a net loss of shoreline ecological functions. (2) The shoreline stabilization structure is evaluated by the hierarchy in subsection F4aiii of this Section. (d) Protect Navigability: To protect the navigability of a designated harbor area when necessity is demonstrated in the following manner by a geotechnical report: (1) Nonstructural measures, planting vegetation, or installing on-site drainage improvements, are not feasible or not sufficient. (2) The shoreline stabilization structure together with any compensatory mitigation proposed by the applicant and/or required by regulatory agencies is not expected to result in a net loss of shoreline ecological functions. (3) The shoreline stabilization structure is evaluated by the hierarchy in subsection F4aiii of this Section. v. Content of Geotechnical Report: Geotechnical analysis pursuant to this Section that addresses the need to prevent potential damage to a primary structure shall address the necessity for shoreline stabilization by estimating time frames and rates of erosion and report on the urgency associated with the specific situation. The geotechnical analysis shall evaluate the need and effectiveness of both hard and soft armoring solutions in preventing potential damage to a primary structure. Consideration should be given to permit requirements of other agencies with jurisdiction. vi. Stream Bank Protection Required: New or expanded shoreline stabilization on streams should assure that such structures do not unduly interfere with natural stream processes. The Administrator of the Department of Community and Economic Development or designee shall review the proposed design for consistency with State guidelines for stream bank protection as it relates to local physical conditions and meet all applicable criteria of the Shoreline Master Program, subject to the following: (a) A geotechnical analysis of stream geomorphology both upstream and downstream shall be performed to assess the physical character and hydraulic energy potential of the specific stream reach and adjacent reaches upstream or down, and assure that the physical integrity of the stream corridor is maintained, that stream processes are not adversely affected, and that the revetment will not cause significant damage to other properties or valuable shoreline resources. (b) Revetments or similar hard structures are prohibited on point and channel bars, and in salmon and trout spawning areas, except for the purpose of fish or wildlife habitat enhancement or restoration. (c) Revetments or similar hard structures shall be placed landward of associated wetlands unless it can be demonstrated that placement waterward of such features would not adversely affect ecological functions. (d) Revetments or similar structures shall not be developed on the inside bend of channel banks in a stream except to protect public works, railways and existing structures. (e) Revetments shall be designed in accordance with WDFW stream bank protection guidelines. (f) Groins, weirs and other in-water structures may be authorized only by Shoreline Conditional Use Permit, except for those structures installed to protect or restore ecological functions, such as woody debris installed in streams. A geotechnical analysis of stream geomorphology both upstream and downstream shall document that alternatives to in- water structures are not feasible. Documentation shall establish impacts on ecological functions that must be mitigated to achieve no net loss. b. Design Criteria for New or Expanded Shoreline Stabilization Structures: When any structural shoreline stabilization measures are demonstrated to be necessary, the following design criteria shall apply: i. Professional Design Required: Shoreline stabilization measures shall be designed by a qualified professional. Certification by the design professional may be required to ensure that installation meets all design parameters. ii. General Requirements: The size of stabilization measures shall be limited to the minimum necessary. Use measures shall be designed to assure no net loss of shoreline ecological functions. Soft approaches shall be used unless demonstrated not to be sufficient to protect primary structures, dwellings, and businesses or to meet resource agency permitting conditions. iii. Restriction of Public Access Prohibited: Publicly financed or subsidized shoreline erosion control measures shall be ensured to not restrict appropriate public access to the shoreline except where such access is determined to be infeasible because of incompatible uses, safety, security, or harm to ecological functions. See public access provisions; WAC 173-26-221(4). Where feasible, ecological restoration and public access improvements shall be incorporated into the project. iv. Restriction of Navigation Prohibited: Shoreline stabilization should not be permitted to unnecessarily interfere with public access to public shorelines, nor with other appropriate shoreline uses including, but not limited to, navigation, public or private recreation and Indian treaty rights. v. Aesthetic Qualities to Be Maintained: Where possible, shoreline stabilization measures shall be designed so as not to detract from the aesthetic qualities of the shoreline. vi. Public Access to Be Incorporated: Required restoration and/or public access should be incorporated into the location, design and maintenance of shoreline stabilization structures for public or quasi-public developments whenever safely compatible with the primary purpose. Shore stabilization on publicly owned shorelines should not be allowed to decrease long-term public use of the shoreline. c. Existing Shoreline Stabilization Structures: Existing shoreline stabilization structures not in compliance with this Code may be retained, repaired, or replaced if they meet the applicable criteria below: i. Repair of Existing Structures: An existing shoreline stabilization structure may be repaired as long as it serves to perform a shoreline stabilization function for a legally established land use, but shall be subject to the provisions below if the land use for which the shoreline stabilization structure was constructed is abandoned per RMC 4-10-060, Nonconforming Uses, or changed to a new use. ii. Additions to Existing Structures: Additions to or increases in size of existing shoreline stabilization measures shall be considered new structures. iii. Changes in Land Use: An existing shoreline stabilization structure established to serve a use that has been abandoned per RMC 4-10-060, Nonconforming Uses, discontinued, or changed to a new use may be retained or replaced with a similar structure if: (a) There is a demonstrated need documented by a geotechnical analysis to protect principal uses or structures from erosion caused by currents or waves; and (b) An evaluation of the existing shoreline stabilization structure in relation to the hierarchy of shoreline stabilization alternatives established in subsection F4aiii of this Section shows that a more preferred level of shoreline stabilization is infeasible. In the case of an existing shoreline stabilization structure composed of rigid materials, if alternatives (a) through (c) of the hierarchy in subsection F4aiii of this Section would be infeasible then the existing shoreline stabilization structures could be retained or replaced with a similar structure. iv. Waterward Replacement Prohibited for Structures Protecting Residences: Replacement walls or bulkheads, if allowed, shall not encroach waterward of the ordinary high-water mark or existing structure unless the residence was occupied prior to January 1, 1992, and there are overriding safety or environmental concerns. In such cases, the replacement structure shall abut the existing shoreline stabilization structure. v. Restoration and Maintenance of Soft Shorelines Allowed: Soft shoreline stabilization measures that provide restoration of shoreline ecological functions may be permitted waterward of the ordinary high-water mark. Replenishment of substrate materials to maintain the specifications of the permitted design may be allowed as maintenance. vi. No Net Loss: Where a net loss of ecological functions associated with critical habitats would occur by leaving an existing structure that is being replaced, the structure shall be removed as part of the replacement measure. E. Use Regulations 9. Residential Development: a. Single Family Priority Use and Other Residential Uses: Single family residences are a priority on the shoreline under the Shoreline Management Act (RCW 90.58.020). All other residential uses are subject to the preference for water-oriented use and must provide for meeting the requirements for ecological restoration and/or public access. b. General Criteria: Residential developments shall be allowed only when: i. Density and other characteristics of the development are consistent with the Renton Comprehensive Plan and Zoning Code. ii. Residential structures shall provide setbacks and buffers as provided in subsection D7a of this Section, Shoreline Bulk Standards, or as modified under subsection F1 of this Section, Vegetation Conservation. c. Public Access Required: Unless deemed inappropriate due to health, safety, or environmental concerns, new single family residential developments, including subdivision of land for ten (10) or more parcels, shall provide public access in accordance with subsection D4 of this Section, Public Access. Unless deemed inappropriate due to health, safety or environmental concerns, new multi-family developments shall provide a significant public benefit such as providing public access and/or ecological restoration along the water’s edge. For such proposed development, a community access plan may be used to satisfy the public access requirement if the following written findings are made by the Administrator of the Department of Community and Economic Development or designee: i. The community access plan allows for a substantial number of people to enjoy the shoreline; and ii. The balance of the waterfront not devoted to public and/or community access shall be devoted to ecological restoration. d. Shoreline Stabilization Prohibited: New residential development shall not require new shoreline stabilization. Developable portions of lots shall not be subject to flooding or require structural flood hazard reduction measures within a channel migration zone or floodway to support intended development during the life of the development or use. Prior to approval, geotechnical analysis of the site and shoreline characteristics shall demonstrate that new shoreline stabilization is unlikely to be necessary for each new lot to support intended development during the life of the development or use. e. Critical Areas: New residential development shall include provisions for critical areas including avoidance, setbacks from steep slopes, bluffs, landslide hazard areas, seismic hazard areas, riparian and marine shoreline erosion areas, and shall meet all applicable development standards. Setbacks from hazards shall be sufficient to protect structures during the life of the structure (one hundred (100) years). f. Vegetation Conservation: All new residential lots shall meet vegetation conservation provisions in subsection F1 of this Section, Vegetation Conservation, including the full required buffer area together with replanting and control of invasive species within buffers to ensure establishment and continuation of a vegetation community characteristic of a native climax community. Each lot must be able to support intended development without encroachment on vegetation conservation areas, except for public trains and other uses allowed within such areas. Areas within vegetation conservation areas shall be placed in common or public ownership when feasible. g. New Private Docks Restricted: All new subdivisions shall record a prohibition on new private docks on the face of the plat. An area reserved for shared moorage may be designated if it meets all requirements of the Shoreline Master Program including demonstration that public and private marinas and other boating facilities are not sufficient to meet the moorage needs of the subdivision. h.     Floating Residences Prohibited: Floating residences are prohibited. Sarah SandStrom Senior Fisheries Biologist 750 Sixth Street South Kirkland, WA 98033 (425) 822-5242 x209 watershedco.com Andy Loos Project No. 18101829 SRM Development 10/30/2018 17 Appendix D INTEGRATED STREAMBANK PROTECTION GUIDELINES Michelle Cramer P.E.1, Ken Bates P.E. 2, Dale E. Miller3 ABSTRACT: Washington State’s Integrated Streambank Protection Guidelines provide advice for the selection and design of streambank protection techniques that protect or restore aquatic and riparian habitats. Protecting and restoring these habitats will provide essential functions for a healthy and productive natural system while at the same time prevent or minimize bank erosion damage. Too often these habitats have been ignored in favor of developing or protecting other floodplain uses and have not successfully mitigated habitat impacts. By understanding river processes, designs for streambank protection can optimize the potential to maintain fluvial integrity and provide habitat. Natural river processes should be integrated into selecting and designing bank protection projects. Integrated streambank protection requires a change in the traditional approach; bank protection measures should be selected to address site- and reach-based conditions and to avoid habitat impacts rather than automatically applying traditional methods such as riprap. This new approach allows for consideration of other methods such as roughening a bankline, directing flow away from an eroding bank, revegetation, floodplain management, landuse planning, maintaining riparian corridors, restoring oxbows/wetlands, relocating infrastructures at risk, managing meander belts, and public education. It may also lead to a recommendation of not allowing specific bank protection projects. KEY WORDS: streambank protection, assessment, risk, habitat, mitigation, design INTRODUCTION The State of Washington is in the final process of developing a document entitled “Integrated Streambank Protection Guidelines” (ISPG) (Washington Department of Fish and Wildlife, 2000) for use by a wide variety of technical and laypersons. Integrated streambank protection is the recognition, assessment, and assimilation of erosion and channel processes, habitat considerations, mitigation requirements, levels/types of risk, project objectives, design criteria, and attributes of bank protection techniques. Guidance is provided on how to assess these factors and how to use the results from the assessments to select appropriate bank protection solutions. A graphical representation of the integrated streambank protection process is shown in Figure 1. There are a number of fundamental guiding principals that comprise integrated streambank protection: · erosion is a natural process that is essential to ecological health; · erosion is often exacerbated or caused by human activities; · causes of erosion (not just symptoms must be solved when appropriate; · basin, reach and meander belt management are essential to integrated streambank projects; · habitat protection must be assimilated into streambank projects; · mitigation sequencing must be integrated into streambank projects; and · impacts to natural channel processes must be mitigated. Identification of suitable bank protection treatments begins with an understanding of the specific mechanism of failure at a project site as well as the site- and reach-based causes of bank erosion. The mechanism of failure is the physical action or process within the bank and can be thought of as the problem you see on site. The site-and reach-based causes are what activates the mechanism of failure. These causes may be simple and discreet, or they may be highly dependent and difficult to separate. Table 1 lists typical mechanisms of failure and corresponding site- and reach based causes of bank erosion. These guidelines are intended to provide a framework for the selection of techniques that promote an understanding of the erosion problem and ultimately, innovative and habitat-friendly solutions. As such, the design process advocated here is not linear. Developing effective, creative solutions requires a clear definition and understanding of why a bank is eroding. Once this is understood, the art and science of integrating this information with habitat considerations, mitigation requirements, levels/types of risk, project objectives, and design criteria can result in the selection of appropriate, habitat-friendly bank protection treatments. 1 Senior Environmental Engineer, Washington Department of Fish and Wildlife-Habitat Program, 600 Capitol Way N. , Olympia, WA 98501, (360)/902-2610, cramemlc@dfw.wa.gov. 2 Chief Habitat Engineer, Washington Department of Fish and Wildlife-Habitat Program, 600 Capitol Way N. , Olympia, WA 98501, (360)/902-2545, bateskmb@dfw.wa.gov. 3 Principal, Inter-Fluve, Inc, 25 N. Willson Ave., Suite 5, Bozeman, MT 59715, (406)/586-6926, dale_miller@interfluve.com. FIGURE 1. Integrated Streambank Protection Process, (ISPG) SITE AND REACH ASSESSMENTS Identifying suitable bank protection alternatives begins with an understanding of the specific mechanism(s) of failure as well as the site- and reach-based causes of erosion. Correctly identifying the mechanism(s) and cause(s) of failure is critical to selecting appropriate bank protection solutions. There are five types of mechanism of failure: general bank erosion, scour, mass failure, subsurface entrainment, and avulsion. The cause(s) of failure can be divided into site- or reach-based causes. At times, these causes may be difficult to ascertain, nevertheless the single cause or combined causes can be identified with careful evaluation. Often, the reach-based causes generate site-based causes. Table 1 lists the mechanisms of failure and site- and reach-based causes. The mechanisms and causes listed in the table may be natural or human caused or exacerbated. A site and reach assessment should identify existing habitat conditions and the habitat potential, respectively. During site and reach assessments, it is important to recognize that bank erosion is a natural process where essential habitat functions are often created. For example, an overhanging bank with exposed plant roots provides cover habitat. Considering habitat creation (or conversely, impacts to habitat) resulting from bank erosion is a critical component of site and reach assessments. MITIGATION Bank protection projects can create substantial impacts to fish habitats. As such, every bank protection project should be evaluated with respect to potential mitigation requirements. Before designing a project, attempts should first be made to avoid impacts altogether. Where impacts cannot be avoided, they should be minimized to the extent possible. Where such impacts cannot be avoided, compensatory mitigation will be necessary. The preferred option is to: first, avoid; second, minimize; and third, compensate for impacts. Project Objectives Site Assessment Risk Assessment Assessment Reach Assessment Habitat Assessment Design Criteria Mitigation (avoid, minimize, compensate) Selection Process (screening matrices) Techniques ·flow redirection ·structural ·biotechnical ·internal bank drainage ·avulsion prevention ·channel modification ·no action Mitigation ·avoid impact ·minimize impact ·compensate for impact TABLE 1. Mechanisms of Failure, Site- and Reach-Based Causes Mechanism of Failure Site-Based Causes Reach-Based Causes General Bank Erosion Reduced vegetative bank structure Tailout and backwater bars Smoothed channel Along a bend (bend scour) Meander migration Aggradation ·reduced hydrology/increased sediment supply ·localized downstream constriction ·reduced slope ·confined channel Degradation ·increased hydrology/reduced sediment supply ·localized shortened channel ·natural channel evolution ·change in long-term watershed hydrology Scour ·Local Scour Woody debris Bridge pier or abutments Boulder/outcropping Not applicable ·Constriction Scour Bridge/road approach Existing bank feature Large woody debris jam Not applicable ·Drop/Weir Scour Weir, ledge, or sill Not applicable ·Jet Scour Lateral bar Side-channel or tributary Abrupt channel bend (energy sink) Subchannels in a braided channel Not applicable Mass Failure Saturated soils Increased surcharge Loss of root structure Removal of lateral/underlying support Meander migration Aggradation ·reduced hydrology/increased sediment supply ·localized downstream constriction ·reduced slope ·confined channel Degradation ·increased hydrology/reduced sediment supply ·localized shortened channel ·natural channel evolution ·change in long-term watershed hydrology Subsurface Entrainment Groundwater seepage Rapid drawdown Not applicable Avulsion/ Floodplain Erosion Floodplain activities Natural conditions Aggradation Previously relocated channel Braided channel Large storm event The first priority of regulatory agencies normally is for the project to be designed so impacts are avoided. If an impact cannot be avoided, then direct effects, such as hardening a bank, are mitigated by restoring damaged or lost ecological functions. Indirect effects are addressed by recognizing long- and short-term impacts to the reach and mitigating for them in the design or off-site. Indirect effects might include the loss of valuable future side-channel habitat and sources of spawning gravel and large woody debris. These losses in habitat arise from bank hardening practices, which prevent the channel from migrating laterally (Dillon, 1998). These impacts are most critical in undisturbed river reaches since the first bank protection project will often promulgate more bank protection projects. They are also critical in developing watersheds where landowners expect stream channels not to move. RISK Throughout the design process, it is important to understand and evaluate the many types and levels of risk associated with a bank protection project. A risk assessment should consider both the risk of continued bank erosion and the risk associated with the bank protection project with respect to property, habitat, and public safety. All bank protection projects contain some level of risk. For example, a bank protection project may be effective at lower flows, but may fail as a result of a larger flood. Likewise, the quality of fish cover habitat along an undercut, vegetated streambank may be at risk by the placement of bank protection techniques (Peters, 1998). Low erosion risk to property and public safety deserves bank protection treatment of comparable risk that allows the bank to continue to erode but at a more gradual, natural rate. OBJECTIVES AND DESIGN CRITERIA Solving a bank protection problem begins with clearly stating the objectives of a project. Objectives are typically somewhat general or qualitative. For example, objectives may be stated as “preventing further erosion of the river along the highway” or “stabilizing the streambank to reduce loss of cropland”. In fact, there are usually a number of objectives with differing levels of priority. For example, either of these objectives should often include “maintaining the aesthetic qualities of a streambank environment” or “protecting or enhancing fish habitat”. In order to bridge objectives with selection of techniques, it is important that design criteria are established. These criteria, considering risk and cost, and stratified according to relative priority, outline the objectives of the project and provide the foundation for making design decisions about the specific sizes and components of bank protection techniques. SELECTION OF TECHNIQUES One of the most difficult but important aspects of the design process is moving from the site and reach assessments to the selection of an appropriate solution. Three screening matrices were developed to assist the user in the selection of bank protection treatments that: · perform adequately to meet bank protection objectives; · are appropriate with respect to mechanism(s) of failure and site-and reach-based cause(s); · are considered with an understanding of the potential impacts to habitat caused by each technique; and · are selected in order of priority that first avoid, second minimize, and lastly compensate for habitat impacts. These matrices act progressively as selective screens, or filters, of bank protection techniques. These matrices are: · Screening Treatments Based on Site Identified Mechanism of Failure · Screening Treatments Based on Reach Identified Causes · Screening Treatments Based on Habitat Protection and Mitigation Within each matrix, bank protection techniques are listed. Each technique is rated such that the applicability of each technique can be considered. This consideration results in accepting or rejecting a technique within the matrix. With each subsequent matrix, techniques are progressively “screened out”, leaving a suite of feasible techniques. Throughout the process of identifying a technique, the question should always be posed whether the best course of action might involve none at all. BANK PROTECTION TECHNIQUES Information about streambank protection techniques applicable within the State of Washington is provided in these guidelines. The techniques have been divided into seven functional groups as shown in Table 2. For each technique, the following information is provided in the guidelines: · Description of the technique; · Application (typical application, variations, emergency, site and reach limitations); · Effects; · Design; · Habitat considerations (mitigation requirements for the technique or mitigation benefits provided by the technique); · Risk (risk to habitat, adjacent properties, and reliability/uncertainty of the technique); · Construction considerations (material required, timing considerations, cost); · Operation and maintenance needs; · Monitoring considerations by case studies; · Examples (typical drawings, site example, description, photographs); and · References. TABLE 2. List of bank protection techniques organized by functional group. In-Stream Flow Redirection Techniques Structural Bank Protection Techniques Biotechnical Bank Protection Techniques Internal Bank Drainage Techniques Avulsion and Chute Cutoff Prevention Techniques Channel Modification Techniques No Action ·groins ·buried groins ·barbs ·engineered debris jam ·drop structure ·porous weir ·anchor points ·roughness tress ·riprap ·log toe ·rock toe ·cribwalls ·ballast ·manufactured retention system ·woody plantings ·herbaceous cover ·soil reinforcement ·riparian buffer ·coir and straw logs ·bank reshaping ·buffer management ·chimney drain ·collector drains ·floodplain roughness ·headcut prevention (grade control) ·floodplain flow spreader ·construct overflow channels Separate guidelines are currently being developed for channel modification techniques. CONCLUSIONS Integrated bank protection is the assimilation of three factors; cause of bank failure, habitat, and risk; into the planning and design of a streambank protection project. It is crucial to assess these factors at the onset, otherwise a bank protection project will not likely achieve ecological and structural success. Many bank protection projects have been constructed with consideration of no more than one of these factors, the risk of erosion. The ISPG provides guidance on: assessing site- and reach-based processes that may be triggering erosion; identifying project objectives and design considerations; identifying existing and potential habitat conditions; and assessing risk. One of the most difficult but important aspects of integrated bank protection is moving from the assessment and identification of project objectives/design criteria to the selection of an appropriate bank protection solution. Three screening matrices were developed to progressively screen-out techniques, leaving a suite of favorable techniques. Mitigation is a crucial component to the selection of bank protection treatment. Techniques must first be selected that avoid impacts to habitat. Only after exhausting the practicality of applying techniques that avoid impacts, can other habitat impacting techniques be selected. These impacts must be mitigated. Detailed design information for bank protection techniques is provided in the guidelines. ACKNOWLEDGEMENTS The Washington Departments of Fish and Wildlife, Ecology, and Transportation and the Washington Salmon Recovery Funding Board jointly funded the Integrated Streambank Protection Guidelines document. Several authors jointly wrote this document from the Washington Department of Fish and Wildlife and Inter-Fluve, Inc. The primary authors are: Washington Department of Fish and Wildlife: Ken Bates and Michelle Cramer Inter-Fluve Consultants, Inc: Dale Miller, Karin Boyd, Lisa Fotherby, and Todd Hoitsma REFERENCES Dillon, J., T. Littleton, and J. Laufle, 1998. Literature Review of Revetment and Channelization Impacts on Pacific Northwest Aquatic Resources with Implications to Skagit River, Washington. U.S. Army Corps of Engineers, Seattle District. Seattle, Washington, pp.10-13. Peters R.J., B.R Missildine, and D.L. Low, 1998. Seasonal Densities Near River Banks Stabilized with Various Stabilization Methods. U.S. Fish and Wildlife Service, Western Washington Office, Lacey, Washington, pp. 26-28. Washington Department of Fish and Wildlife and Inter-Fluve Inc., 2000. Draft Washington State Integrated Streambank Protection Guidelines. Olympia, Washington. Andy Loos Project No. 18101829 SRM Development 10/30/2018 18 Appendix E Primary access path Secondary access connection Public amenity opportunity (vegetation with bench, viewpoint, or flexible open space) Public access node and viewpoint Restoration planting - mixed riparian vegetation, herbaceous and woody shrubs Restoration planting - clustered tree planting View preservation area Rev. September 2018RENTON, WA SRM CEDAR RIVER APARTMENTS SHORELINE BUFFER DIAGRAMMATIC + COURT CONCEPT PLAN © 2018, The Watershed Company, all rights reserved. Cedar River 1 12 3 4 4 5 4 1 Existing bulkhead wall to remain 2 Lowered bulkhead wall 3 Grade separation 4 Public shared-use trail (ADA-accessible) 5 Pool (private amenity) 6 Rooftop lounge (private amenity) 7 Multi-use private plaza 8 Existing trees to remain Private amenity opportunity (sport court, barbecue, picnic, courtyard, patio, or flexible open space) Fire truck access path (grasscrete) Private access only CONNECTION TO ADJACENT PUBLIC USES SIDEWALK CONNECTION 6 7 8 Vegetated screen Shoreline buffer (100 feet) 8 3 Andy Loos Project No. 18101829 SRM Development 10/30/2018 19 Appendix F October 2018 F-1 18101829 f_example log jam projects_revd Project Title: Upper Washougal River Restoration (Phases 1, 2, and 3) Cost: $800,000 Location: Washougal River Latitude: 45.663° Longitude: -122.168° Photo Source: The Columbian http://www.columbian.com/news/2011/aug/31/Upper-washougal-river-restoration-moves-ahead/ PHOTOGRAPH 1 Logs anchored into scoured bedrock to restore natural fish habitat. PHOTOGRAPH 2 Chained log anchors on Washougal River. October 2018 F-2 18101829 f_example log jam projects_revd Project Title: North Fork Stillaguamish Engineered Log Jams Cost: $ 621,384 Location: North Fork Stillaguamish River Latitude: 48.420° Longitude: -121.667° Photo Source: Stillaguamish Tribe of Indians https://secure.rco.wa.gov/prism/search/projectsnapshot.aspx?ProjectNumber=07-1737 PHOTOGRAPH 3 Newly constructed ELJ (engineered log jam) PHOTOGRAPH 4 Reach of Stillaguamish where new ELJs were installed and existing structures repaired. October 2018 F-3 18101829 f_example log jam projects_revd Project Title: Saxon Reach Restoration Project Cost: $1,180,247 Location: South Fork Nooksack River Latitude: 48.774° Longitude: -122.213° Photo Source: Lummi Nation https://secure.rco.wa.gov/prism/search/ProjectSnapshot.aspx?ProjectNumber=10-1300 PHOTOGRAPH 5 Log revetment and ELJ looking toward Saxon Bridge PHOTOGRAPH 6 ELJ #3 with scour pool and log piles October 2018 F-4 18101829 f_example log jam projects_revd Project Title: Riverberry-Davis VanDellen Project Location: Nooksack River Latitude: 48.882° Longitude: -122.327° Photo Source: Whatcom County PHOTOGRAPH 7 Aerial view during construction looking upstream, and zoomed view of installed LWD structures looking downstream (post- construction), see zoomed view corresponding to dashed box area. PHOTOGRAPH 8 Aerial view during construction looking downstream, and zoomed view looking downstream of bendway weir(s) using rock riprap and dolo materials installed on right bank of Nooksack, see zoomed view corresponding to dashed box area. October 2018 F-5 18101829 f_example log jam projects_revd Project Title: Hoh River Bank Stabilization Site #1 Cost: $7,000,000 Location: Hoh River Latitude: 47.782° Longitude: -124.261° Photo Source: Herrera Environmental Consultants Inc. http://www.fhwa.dot.gov/publications/publicroads/06jan/05.cfm PHOTOGRAPH 9 Installed 4 mid-channel ELJ structures, and armored bank where it was attacking the highway alignment using riprap and logs with rootwads and included six ELJs along roadbank and two smaller ELJs to prevent erosion of the highway embankment. PHOTOGRAPH 10 Large spruce trees placed between H-piles with stream boulders and river gravel filling in the inner matric to add buoyancy resistance. October 2018 F-6 18101829 f_example log jam projects_revd Project Title: Lower Germany Creek Restoration Project (Phases 1 and 2) Location: Germany Creek Latitude: 46.191° Longitude: -123.124° Photo Source: Wild Fish Conservancy http://wildfishconservancy.org/projects/germany-creek PHOTOGRAPH 11 Placement of LWD as part of bank stabilization on Lower Germany Creek PHOTOGRAPH 12 Less invasive measure securing log jam structure using large dolosse. October 2018 F-7 18101829 f_example log jam projects_revd Project Title: Mashel River Restoration Project Cost: $1,254,992 Location: Mashel River Latitude: 46.860° Longitude: -122.270° Photo Source: Nisqually Indian Tribe https://secure.rco.wa.gov/prism/search/projectsnapshot.aspx?ProjectNumber=09-1393 PHOTOGRAPH 13 Log revetment and ELJ looking toward Saxon Bridge PHOTOGRAPH 14 ELJ #3 with scour pool and log piles October 2018 F-8 18101829 f_example log jam projects_revd Project Title: SR 20 Skagit River – CED Permanent Restoration Project Location: Skagit River Latitude: 48.499° Longitude: -121.528° Photo Source: Washington Department of Transportation (WSDOT) http://www.flickr.com/photos/wsdot/ PHOTOGRAPH 15 Staging of dolosse anchored to log bundles as delivered from manufacturer PHOTOGRAPH 16 Trackhoe with grapple placing log and dolos bundles for first layer of engineered log jam Andy Loos Project No. 18101829 SRM Development 10/30/2018 20 Page Left Intentionally Blank