Lower East Fork Grays Restoration

The Cowlitz Indian Tribe proposes to build log jams on 1.3 miles of stream channel to reconnect floodplains and improve in-stream habitat for salmon and steelhead in the lower East Fork Grays River. Preliminary designs for this project have been completed with funding from the SRFB Lower East Fork Grays Design project (#18-1389), and material (logs and whole trees) will be provided by the 2018-2020 WCRRI Grays River Headwaters Restoration Project (#18-2162). This project will create other engineered structures which indlude channel spanning structures, complexity jams, and non-ELJ structures to arrest channel incision, dramatically roughen the channel and floodplain, restore floodplain connectivity, increase sediment deposition, enhance instream habitat complexity, and restore the resiliency of the lower East Fork Grays River, benefitting populations of winter steelhead and coho salmon. Project work will also include riparian planting to enhance the overall goals.

The goal of this project is not easily achieved in a single phase or treatment, instead this project is the first step in a multi-phased, process-based restoration approach to slow the transport of sediment from the upper watershed. The overarching goal to retain sediment, requires the placement of large quantities of instream wood to reconnect floodplains and trap sediment in the upper basin. This project will place three types of log structures to retain spawning gravels suitable for spawning, re-engage floodplains to dissipate the hydraulic energy and aggrade sediment. The final designs of this project will likely be replicated and utilized for future treatment phases in the surrounding tributaries of the upper Grays River watershed.