Five Rivers Sub-basin Large Wood Helicopter Treatment Project Phase I

The Five Rivers Large Wood Helicopter Project will take place in four tributaries of the Five Rivers Sub-basin of the Alsea River on lands managed by the U.S. Forest Service (USFS) and the Bureau of Land Management (BLM). The Alsea River Basin is located in the Oregon Mid-Coast and its drainage consists of 466 square miles. The basin supports Oregon Coast (OC) Coho Salmon, which, in 1998, were listed under the Endangered Species Act (ESA). A recent assessment by Oregon Department of Fish and Wildlife (ODFW) found the Alsea OC Coho population is not meeting its viability goal for ESA-delisting. ODFW and NOAA identified instream complexity and water quality as the limiting factors. Industrial timber harvest has had significant impacts to stream habitat quality throughout the Oregon Coast Range. Activities such as road building, logging large diameter trees within riparian areas, and the removal of large woody debris reduced stream habitat complexity, adversely impacting the abundance and survival of salmonids. This proposal is Phase 1 of 2 and funds the large wood treatment of Upper Five Rivers, Green River, East Fork Lobster Creek, and South Fork Lobster Creek using a Chinook helicopter to place whole trees in approximately 4 miles of stream to increase instream complexity and restore natural form and function. This project will be implemented during the Summer/Fall of 2024. Project partners include the Oregon Department of Fish & Wildlife, U.S. Forest Service, Bureau of Land Management, and the Oregon Wildlife Foundation.

The actions proposed in the Five Rivers Sub-basin Large Wood Helicopter Placement Project will directly address the primary limiting factor by adding large wood to 4 miles of Coho spawning and rearing habitat in Upper Five Rivers, Green River, East Fork Lobster Creek, and South Fork Lobster Creek. The addition of large wood in these creeks will lead to an increase in stream complexity and spawning and rearing habitat for Coho Salmon and other anadromous fish, addressing the primary limiting factors for Coho Salmon recovery as described in NOAA NMFS 2016 Oregon Coast Coho Recovery Plan and the ODFW Oregon Coast Coho Conservation Plan (2007). Additionally, large wood plays an important role in many processes of a healthy aquatic ecosystem, including by creating low velocity refuge for juveniles during high flow events, sorting of gravels, to create spawning habitat, providing floodplain connectivity, creation of pools as well as off channel habitat.