Overview: The Tucannon River in Southeast Washington flows north out of the Blue Mountains into the Snake River, and is the ancestral boundary between the Confederated Tribes of the Umatilla Indian Reservation and the Nez Perce Tribe. The Tucannon watershed supports the only remaining population of spring Chinook (Oncorhynchus tshawytscha) in the lower Snake River. Early fish estimates show the Tucannon once produced thousands of salmon annually, but now only produces a few hundred adult spring Chinook each year. In 1992, spring Chinook were listed as threatened under the Endangered Species Act as runs declined to less than 200 adult fish. Because of the Tucannon River’s importance to the Snake River Basin, BPA provides funding for a Programmatic Habitat Project in the Tucannon River.

The Tucannon Programmatic Project is managed by the Snake River Salmon Recovery Board (SRSRB) through a parent contract for operational support, organizational management, implementation assistance, and annual reporting. The goal of the Tucannon River programmatic is to restore natural channel processes in the spring Chinook priority restoration reaches of the Tucannon River, leading to improved population productivity and abundance. The Nez Perce Tribe (NPT) collaborates in the Programmatic Project as a project implementer in support of programmatic goals: a desired riverine system that is shaped and maintained by the dynamic interactions and interconnections of its natural physical and ecological processes. The restoration actions proposed for implementation in the prioritized river segments promote and enhance the interconnected nature of: a) hydrology, b) geomorphology, c) connectivity, d) riparian community, and e) aquatic biota.  

Background: After several years of opportunistic restoration in the Tucannon Basin, as a Model Watershed (1997-2008), the Columbia County Conservation District (CCD) brought all parties to the table to work on a new restoration planning document. The Tucannon River Geomorphic Assessment & Habitat Restoration Study (Anchor QEA, April 2011) identified and prioritized stream reaches and restoration actions which would best improve habitat for salmonids. Refocusing on the high priority areas for spring Chinook, the CCD coordinated the development of a habitat restoration plan that prioritized work from RM-20 upstream to RM-50. After 10 years of implementing the first plan, it became obvious that program managers needed to move further down the watershed and start working in the lower Tucannon River. In 2018, through the Tucannon River Programmatic Habitat project, the CCD initiated an update of the Tucannon Restoration Plan to help refocus restoration efforts and include the rest of the Tucannon River from RM-20 downstream to the confluence of the Snake River.

The Updated Tucannon Conceptual Restoration Plan (Anchor QEA, 2021) prioritizes projects into three Tiers (1-3) based on these prioritization goals: (1) increased complexity at low-winter flows, (2) increased complexity during spring and winter peak flows, (3) reconnection of disconnected and abandoned floodplains, (4) improved quantity and quality of pools, and (5) increased retention and storage of in-channel bedload sediments.  

Summary: In 2014 WDFW completed the development of the W.T. Wooten Wildlife Area Floodplain Management Plan, which was developed as a plan to define and conduct management activities for seven manmade lakes and their supporting infrastructure (e.g., diversion structures and riprap levees) located on the floodplain of the Wildlife Area. In 2011, the benefits of removing or changing the configuration of the lakes were not included in the project concept development or within the prioritization framework, and consequently they were not considered in the Geomorphic Assessment & Restoration Prioritization update, completed in early 2021. During the previous spring, significant flooding disabled the utility and function of several of the lakes and their supporting infrastructure, opening an opportunity for reconsideration of the restoration potential in this 14-mile reach of the river. In 2023, a broad group of partners, including the co-managers (NPT, CTUIR, WDFW), elected to evaluate the physical impacts of the lakes, consider alternatives, develop initial strategies and preliminary project concepts, and explore possible restoration approaches as a basis for priority actions that could contribute significantly to achieving the habitat restoration objectives and fish recovery goals for the watershed. The initial findings from this assessment identified the failing infrastructure of the Big 4 lake impoundment as a priority for restoration action.

Current Emphasis: Supported by this contract, the NPT is partnering with WDFW, CTUIR, and SRSRB to prepare for the construction phase of the Big 4 restoration project (anticipated in 2026). We will begin site access, site prep, and material staging for the larger project. The timeline for site access will be in early fall of 2025 and materials staging in spring of 2026. The designs for this project are under contract 73982 REL164 & REL 222.  The Big 4 restoration project will remove manmade features (e.g., lake intake and return channels, pushup berms) to improve natural floodplain connectivity, address the incision that has resulted from the lake laterally confining the floodplain, and enhance habitat complexity tor aquatic species. The extent of the project area is 2.05 valley miles and 2.37 miles of stream length along the Tucannon River in the vicinity of Big Four Lake on the W.T. Wooten Wildlife Area, which is owned and operated by the Washington Department of Fish and Wildlife (WDFW). The project is co-managed by the Confederated Tribes of the Umatilla Indian Reservation (CTUIR), Nez Perce Tribe (NPT), and Washington Department of Fish and Wildlife (WDFW). The project reach is identified as Project Areas (PA) 10.3 through 8 in the Conceptual Restoration Plan (Anchor QEA, 2011b)

The goal of the project is to improve and restore the system’s ability to support bull trout, lamprey, mussels, and threatened Snake River steelhead and spring Chinook salmon in the Tucannon River Basin. The ecologic concerns affecting the reach that can be addressed specifically by this project include: high stream power and water temperatures; insufficient pools; lack of pools; shortage of LWD; loss of riparian vegetation; insufficient large wood recruitment; stream-valley floor hydrologic connection; channel form, stability, sinuosity, pool/riffle ratios and aquatic fish habitat complexity; substrate embeddedness; wetland state; and beaver habitat. This project contributes to a programmatic effort to return the Tucannon River corridor to historic functioning capabilities to not only provide improved habitat for native fish species, but also to provide suitable habitat to promote the return of wildlife and native plants.