F24AS00364 Feather River/Sutter Bypass Nelson Slough (CDFW Nelson Slough Unit) Floodplain Feasibility for Juvenile Salmonid Habitat Improvement

for a work effort consisting of identification, development and feasibility of a floodplain connectivity solution in Nelson Slough primarily benefiting juvenile salmonids. This will include facilitating meetings with the Technical Advisory Committee, composing of members from United States Fish and Wildlife Service (USFWS), National Marine Fisheries Service, California Department of Fish and Wildlife (CDFW) and California Department of Water Resources (CDWR). The USFWS and Project Management Team intend to use information collected from this study to develop a future habitat restoration project at this site. The project tasks and applicant responsibilities are the following: Information gathering and site reconnaissance; Project Management;Data Collection and Evaluation; Develop a multi-dimensional hydrodynamic flow model to assess floodplain inundation frequencies; Develop a sediment transport model; Landowner access; Facilitate, plan, and provide notes from Technical Advisory Committee meetings; andDevelop juvenile salmonid habitat alternatives (i.e., restoring natural processes, side-channel creation through historic oxbow, floodplain connectivity, etc.).Project The CVPIA SIT and Core Team recommended increasing access to juvenile rearing habitat in lower Feather River and Sutter Bypass and identified it as a high priority for FY2020 (2019 Tech Memo). The project will continue to be funded for planning and analysis in FY2025 with potential construction and implementation in FY2026. The proposed project completes a feasibility study to develop and evaluate potential restoration actions at the Nelson Slough Wildlife Area Unit to increase the frequency with which floodplain habitat is inundated. The project would be located on CDFW property at the confluence of the lower Feather River corridor and the Sutter Bypass near Nelson Slough.The project may include lowering and widening an existing slough within setback levees in the lower Feather River corridor downstream of Highway 99 and tying this into the Sutter Bypass; creating multiple swales within the area; and/or lowering the floodplain terrace. This would allow Feather River basin water to flow into the Sutter Bypass with much greater frequency than under current conditions, thereby connecting remnant floodplain (including an abandoned oxbow from the Feather River) in the lower Feather River corridor with existing floodplain in the Sutter Bypass. Nelson Slough, a 750-acre unit of the Feather River Wildlife Area, is adjacent to more than 3,500 acres of conservation properties along the Feather River and approximately 4,500 acres of conservation properties within the Sutter Bypass. The project could increase floodplain habitat available to Feather, Yuba, and Bear River salmonids by up to 1,000 acres or more under certain flow conditions. Additional floodplain inundation resulting from this project could provide rearing benefits to Sacramento River origin juvenile winter and spring-run Chinook salmon, juvenile Butte Creek spring-run Chinook salmon in the Sutter Bypass, Feather River basin spring-run Chinook salmon, as well as Central Valley steelhead and potentially juvenile green sturgeon. Currently, River Partners has been awarded funds through the CVPIA for improving salmon and steelhead juvenile rearing habitat through creation and restoration of up to five miles of side channels on the Lower Feather River adjacent to the Nelson Slough Wildlife Area Unit. This project could potentially be integrated with the River Partners Lower Feather River Side Channel Restoration Project. The Peterson, Coarse Resolution model Report, 2014 (DSM) suggests that supporting increasing juvenile Chinook size at emigration can be beneficial to the outcome of a greater number of returning adults. Post project monitoring may help improve or validate the hypothesis of the DSM. Supplemental InformationOutcome of the project would achieve the following goals: Increase accessible floodplain for Feather, Yuba, and Bear River salmonids by through increased access; Determination of the amount of accessible acres created at various flow ranges compared to existing conditions with various landscape changes;Reduce habitat fragmentation to improve rearing and emigration corridors; Increase and improve the quantity, quality, and diversity of riverine habitat, including floodplain rearing habitat for juvenile fish; Reduce predation impacts of non-native fish species in channel;Increase native riparian vegetation in restored habitat;Contribute to the recovery of federal and state listed fish populations; and Contribute to the Central Valley Project Improvement Act doubling goal for the Feather, Yuba, and Bear Rivers. Questions that will be addressed in the feasibility study are:Up-to-date topographic and bathymetric LiDAR or similar, relative to project area or any other areas of influence. Characterization of the hydrodynamics that would facilitate floodplain activation. Characterization of the hydrodynamics that would facilitate floodplain activation. Prioritize updating physical habitat characterization.Focus on (potential) instream system parameters (longitudinal profiles, cross section installation and revisiting those, etc.). Using a drone to map area pre-project, as well as post project. Assess:Flood conveyance, flood storage and inundation frequency and duration; Fluvial geomorphic processes;Aquatic and riparian habitat;Project costs;Land availability;Sedimentation;Excavated materials and spoil placements; andInfrastructure (i.e. utility pipelines, roadway bridge abutments).Pre-project assessments: This would include assessing hydrology and water quality, as well as biologic monitoring cataloging insect, bird, and other current animal habitat necessary to understand what the area is currently providing and serve as a baseline for assessing post project performance after implementation. Monitoring and evaluation are essential to determine whether restoration projects are implemented correctly and performing as expected so that we achieve the intended benefits. Wildlife Habitat Area Management Objectives: Current acreage of upland habitat shall not be decreased. Must not fragment current available upland habitat.Any side channels created would require a crossing for wildlife and staff to facilitate bird plants. Species of interest include quail, deer, turkey, pheasant, and multiple waterfowl. No restoration activity shall reduce the various hunting opportunities offered by CDFW on the Nelson Slough Unit (i.e., deer hunt season, waterfowl hunt season, quail hunt season, turkey fall hunt season, turkey spring hunt season, and pheasant hunt season). Awardee will coordinate closely with CDFW wildlife area staff to develop alternatives that do not impact these opportunities for the public. Considerations:Consider restoration design and implementation timing with DWR and Sutter County to complement their future levee improvement work at the Nelson Slough Unit and the surrounding reach of the Feather River and Sutter Bypass as described in the Riparian Restoration Plan for the Nelson Slough Unit (2009 River Partners) Department PriortiesThe mission of the U.S. Fish and Wildlife Service is “working with others to conserve, protect, and enhance fish, wildlife, plants, and their habitats for the continuing benefit of the American people”. Fish and Aquatic Conservation is an integral program within the U.S. Fish and Wildlife Service and supports the mission by working with partners to achieve benefits for aquatic species and their habitats. The U.S. Fish and Wildlife Service plays a key role in addressing the challenges identified in the Biden-Harris administration’s priorities. https://www.fws.gov/initiative/directors-priorities Rebuilding the economy;Tackling climate change;Developing a wildlife conservation strategy for the 21st century;Combating Wildlife Trafficking.