Zmrhal's Coweeman River Project

The Cowlitz Conservation District completed this restoration project on the Coweeman River in Cowlitz County. The project site is upstream of a geologic pinch point that forms a mid channel bar with several side channel areas. The Coweeman River has eroded the existing narrow forested buffer exposing alluvial soils in agriculture landuse and threatens to abandon the side channel habitat. This project improved channel stability and habitat diversity by: 1) establishing 4.5 acres of forested riparian area on 800 feet of streambank, and 2) managing the rate of channel migration to allow the riparian vegetation to get established by implementing a bio-engineering design tha tresulted in a roughened yet deformable stream bank through the use of bank shaping, LWD placement, and use of natural, streambed sized material for toe rock.

This project addressed the needs identified within the Lower Columbia Salmon Recovery Fish & Wildlife Plan and the restoration area for this project is listed as a priority within the Plans Six Year Habitat Work Schedule Addendum. The Coweeman subbasin was identified as one of the most significant areas for salmon recovery among Washington Cascade strata subbasins based on fish population significance and realistic prospects for restoration. This project provides short term and long-term benefits to all life stages of Chinook, coho, and chum salmon and steelhead and cutthroat trout. As stated in the Subbasin Plan, all Coweeman River salmon and steelhead will need to be restored to a high level of viability to meet regional recovery objectives.

The goal of the project is to restore native riparian vegetation along salmon bearing streams. The objective of the project is to restore natural streamside vegetation, improve stream temperature, reduce erosion, filtration, and recruit large woody debris.