In collaboration with the Methow Salmon Recovery Foundation, W2r is leading a design for a major floodplain reconnection (1.75 miles, ~150 acres) along the mainstem Methow River. A major feature of the project is the setback of a County-owned levee enrolled in the USACE PL-84-99 program with additional proposed actions including side channel reconnection, bank stabilization and restoration, and large wood placements. The project is currently in 90% design phase and design submittals have been developed to both BPA HIP review and RCO Manual 18.
Designs are incorporating broad feedback from multiple funders, regulatory agencies, and local stakeholders including Ecology, USACE, FEMA, RCO’s Salmon Recovery Funding Board , Okanogan County, Bonneville Power Administration, and US Bureau of Reclamation, Tribes, and private landowners. With recreational use in the reach, the design has been informed by strong hydraulic modeling and geomorphic/sediment transport analyses to inform river response from proposed restoration actions and to reduce risk to river users and adjacent landowners. W2r collaborated with Reclamation Technical Services Center (TSC) on hydraulic modeling.
In addition to design, W2r is providing technical assistance for project permitting. Floodplain permitting, which is undergoing the CLOMR/LOMR process, has required extensive coordination on flood modeling, channel migration zone considerations, and regulatory analysis between local, state, and federal agencies.
Client
Methow Salmon Recovery Foundation
Keywords
Concept to final design, large wood implementation, levee setback, side channel reconnection, regulatory compliance, geomorphic assessment, hydraulic modeling, sediment transport analysis
