Background:  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 (ESA) as runs declined to less than 200 adult fish. The basin also supports summer steelhead and fall Chinook also protected under ESA.  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, consistent with the Salmon Recovery Plan for SE Washington and the Tucannon Conceptual Restoration Plan (Anchor QEA 2020).  The Restoration Plan’s focus is developing a riverine system that is shaped and maintained by natural physical and ecological processes. The restoration actions proposed for implementation in the prioritized river segments promote and enhance the interconnected nature of hydrology, geomorphology, connectivity, riparian community, and native fish and wildlife.  

Major limiting factors influencing naturally functioning conditions throughout the project reaches proposed for treatment in the watershed include:  

•    Past land use and management practices including logging, grazing, agriculture, channel modification, stream bank armoring, the placement of infrastructure and construction of the Tucannon Lakes in the floodplain, in addition to recent large forest fires in the headwaters, have created conditions in the Tucannon River that have over-simplified the stream channel and drastically reduced the productivity, abundance and sustainability of the spring Chinook population.

•    Channel simplification caused by channel confinement (levees, lakes, roads) and straightening (pushing the channel to the valley wall) has led to a loss of floodplain connectivity (channel incision), increased stream velocities, and loss of pool habitat. These factors have combined to decrease quality habitat for adult and juvenile Spring and Fall Chinook salmon, steelhead, and Bull Trout, leaving these unique populations at risk.

The Updated Tucannon Conceptual Restoration Plan (Anchor QEA, In Process) will prioritize 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) re-connection of disconnected and abandoned floodplains, (4) improved quantity and quality of pools, and (5) increased retention and storage of in-channel bedload sediments. With these new prioritization goals, the Tucannon program implementers will select project areas in the Tucannon that focus on increasing habitat condition for adult and juvenile Snake River spring Chinook, steelhead and Bull Trout. The refocusing of prioritization goals will ensure Tucannon Implementers are selecting project areas for future restoration actions that are large enough to make a meaningful difference, be cost-effective relative to those benefits, and remain feasible to construct.

Project Area Summary:  The project area in Cummings Creek is proposed as a Post Assisted Log structure (PALs) project constructing ~70 log structures/stream mile for the purpose of encouraging channel migration, side channel and floodplain connection as well as an increase in channel habitat unit quantity and diversity.  The project reach begins at the Cummings Creek confluence with the Tucannon upstream ~ 2 miles.  The project has been divided into three phases with Phase I encompassing the downstream mile, Phase II implementing the second upstream mile and Phase III focusing on increasing opportunities within both miles in 2025 following a number of high flow events in Phase I and Phase II.  It is envisioned that this will help maximize habitat opportunities

Project Area Background:  The overall area (2 miles) has been broken into a number of implementation work windows (2023 Phase I, 2024 Phase II and 2025 Phase III) based on available funding, construction capacity and adaptive management considerations.  Phase I design and implementation, was  funded by the Salmon Recovery Funding Board (SRFB) and will be implemented in the 2023 work window.  The design will be attached to this contract for reference and following implementation in 2023, will have a single high-water period to provide design feedback prior to initiating Phase II designs which will be attached to this contract as a concept in the fall of 2023 to initiate BPA's design review process.

Phase II (partially implemented under this contract) will be implemented in 2024, placing ~70 additional structures.  Phase III (not part of this contract) would be funded through a grant obtained from the SRFB and would review the effectiveness of Phase I & II to take advantage of learning in the first two phases. Phase III would capitalize on gains in floodplain connectivity within the two-mile reach, placing an additional 70 structures in 2025.

Phase II Objectives:
•    Place 70 PALs over 1 mile of river channel
•    Improve connection to 10 ac of floodplain
•    Connect on regular frequency ~2 ac of low-lying floodplain.

Final Designs for Phase II will be attached to this contract in CBFish.