Mainstem Touchet Project Area 01 Design

The Walla Walla County Conservation District completed a preliminary engineered design for fish habitat restoration on the mainstem project area (PA) 1 located west of the City of Prescott in Walla Walla County, Washington. This area was identified in the Upper Touchet Basin Plan (2020) as a tier 1 high priority. The site is within a major spawning area for ESA list mid-Columbia River steelhead as identified in the Snake River Salmon Recovery Plan (2011). The overall goal was to create a preliminary engineered design incorporating a series of engineered log structures and bank cuts along one mile to benefit mid-Columbia steelhead adult holding and juvenile rearing and bull trout habitat. The intent of the design was to restore natural river processes including increased channel roughness elements, promote sediment sorting and storage, and large wood features.

This project aimed to produce a preliminary design for stream restoration in the Touchet MS1 project area. The goal of the design was to restore spawning, rearing, and overwintering habitat for
Mid-Columbia steelhead, spring Chinook salmon, and bull trout. The produced design accomplishes this through engineered logjams and pilot cuts to increase habitat diversity and floodplain connection.