Touchet River Mile 42 Design

The Walla Walla County Conservation District hired an engineering team and they created final engineered designs for a fish habitat restoration project. The overall goals of the engineered design are to restore natural riverine processes including increased channel roughness elements, promote sediment sorting and storage, and create a dynamic floodplain and instream environment with complex side channels and large wood features. The project, when constructed, will provide Mid-Columbia steelhead adult holding and juvenile rearing habitat, bull trout overwintering habitat, and spring Chinook passage and holding habitat. A geotechnical memo is included in the engineering report. An alternatives analysis was completed in Oct. 2021, preliminary design Jan. 2022 and final design March 2022. Each stage was reviewed with select stakeholders and RCO review panel members as appropriate. The design includes approximately 2 pilot cuts, 4 pile fields, and 28 engineered log jams.

The overall goals were to create an engineered design that when constructed would restore natural riverine processes including increased channel roughness elements, promote sediment sorting and storage, and create a dynamic floodplain and instream environment with complex side channels and large wood features. This work will benefit Snake River steelhead and Chinook.