The South Fork Clearwater River and Slate Creek watersheds lie within the 1855 ceded territory of the Nez Perce Tribe (NPT). Local oral histories refer to the once significant steelhead and salmon runs found throughout the Clearwater Subbasin. These runs were the backbone of an entire culture and were revered as such. The health of entire watersheds, from ridge-top to ridge-top, is important because watersheds contain an interconnected web of life comprised of many elements that support these fish species.  Because of a long history of anthropogenic land uses in these watersheds, the health has been compromised and therefore threatening the health and productivity of the fish species; restoration in these areas in needed to improve the fish populations.

The Lower South Fork Clearwater (LSFC)/ Slate Creek Watershed Restoration project (2010-003-00) is an on-going project of the Nez Perce Tribe Department of Fisheries Resources Management Watershed Division (NPT DFRM) that originated in 1996. This unique and successful restoration partnership is implemented through agreements between the local partners, NPT, and Bonneville Power Administration. The NPT works with a variety of regional collaborations, primarily the USDA Nez Perce – Clearwater National Forest (NPCNF), to implement high value restoration projects using a process-based approach. The overarching goal of the project is to restore lost fishery resources, which are of cultural significance to the NPT.

The LSFC/ Slate Creek watersheds are important to several fish species including Snake River steelhead and spring/summer Chinook as well as bull trout, Snake River fall Chinook (LSFC alone), westslope cutthroat trout, rainbow trout, Pacific lamprey, and western pearlshell mussels.

The goal of this project is to restore the aquatic ecosystems with process-based restoration in these watersheds, addressing limiting factors so that the physical habitat no longer limits recovery of the Endangered Species Act (ESA) threatened steelhead and Chinook salmon populations with associated benefits to several other focal and secondary species.   As part of ongoing partnerships, the NPT proposes to implement habitat improvement projects to address primary limiting factors that will increase the productivity and viability of the LSFC/ Slate Creek watershed populations.  This proposal’s primary focus is to implement habitat improvement and protection projects to address limiting factors identified in regional guidance documents including: Clearwater Subbasin Plan (2003), Salmon Subbasin Plan (2005), South Fork Clearwater River Landscape Assessment (USFS 1998), NOAA Recovery Plans (2017a and 2017b), and USFWS Bull Trout Recovery Plan (2015).

Specifically, the types of actions the project is proposing are to restore habitat access, floodplain connection, sediment transport, storage and routing of water, plant growth and successional processes, input of nutrients and thermal energy, and nutrient cycling in the aquatic food web.

In FY 23, the NPT will work in partnership with the NPCNF to replace two undersized culverts in the Slate Creek watershed, Peter Ready Creek and Greek Creek crossings. The proposed projects will replace existing undersized culverts with larger span, open bottom structural plate culverts. The proposed designs call for replacement with structures designed for aquatic organism passage and include open bottom channels with continuous native substrate, rock weir grade control structures to allow rest stops through the structure, and streambanks inside of the culvert to create near-margin passage opportunities.  The finished culverts will allow for passage of all stages of fish with native substrate, an at-grade channel, and step pools allowing for upstream migration to an additional 3.14 miles of habitat.

The NPT and NPCNF will also install and maintain BDAs and PALS in Castle Creek in FY 23 that aid in creation of habitat features and allow the stream to access its natural floodplain. Work in this contract will apply these low-tech structures to improve habitat conditions in the straightened channel. The BDAs take some time to accumulate sediment and restore habitat as they are a form of process-based, passive restoration.  Ten BDAs were installed here in 2021 and 2022 per USFS small NEPA and permits, and more will be installed and maintained this coming year in 2023. BDA installation will also occur on private land on Sill Creek, a tributary to Sally Ann Creek.  This project will install four structures along a 170 ft reach in partnership with the USDA’s Natural Resource Conservation Service (NRCS) and the landowner.  The NPT will provide labor for the installation.  Both BDA projects will improve habitat conditions for steelhead and Chinook in the SF Clearwater drainage.

In FY 23, work also includes the completion of a fish passage culvert design at the confluence of Sill Creek and Sally Ann Creek, the last design in a package of four crossings to be replaced in partnership with the Idaho County Roads Department. The Sally Ann/ Sill Creek culvert is an undersized circular culvert that has been crushed by the settling roadway with a perched outlet and stream flow around and under the structure.  The structure has broken midway through the pipe, has holes rusted through the structure, and contains no substrate throughout.  The replacement will increase the hydrologic capacity of the culvert and reduce the chances of failure in the future, preventing excess sediment from entering the South Fork Clearwater River and negatively impacting all life stages of aquatic species, including juvenile Spring Chinook and Steelhead. The new culvert will pass all aquatic organisms, including all life stages of anadromous and resident fish. Field surveys were completed in FY 22 as part of a larger design package in the area and the design work for this culvert replacement will be completed under this contract.  When the project is implemented, it will provide access to approximately 2.6  miles of stream.

A second crossing design on Sally Ann Creek will be completed under this FY 23 contract, just downstream of the Sally Ann/ Sill Creek culvert but under agreement with a private landowner rather than with Idaho County.  This structure is so significantly undersized that it becomes fully submerged under high flow conditions with the stream rising several feet above the top of the inlet during flood events.  Significant backwatering occurs along with bank sloughing and significant erosion.  The crossing will be designed to pass all aquatic organisms, including all life stages of anadromous and resident fish, while reducing sediment into the South Fork Clearwater River.  The NPT will work cooperatively with the NRCS on this design with future implementation partnership opportunities .When the project is implemented, it will provide access to approximately 2.9  miles of stream.

Another design project for future implementation to be designed in FY 23 lies on an approximate 4,000 ft of private land adjacent to the mainstem South Fork Clearwater River. Currently, the landowner has personal property and cattle spread around his land abutting the river, but an unstable bank (an artificial berm/ dike built by the US Army Corps of Engineers circa 1960) is eroding and threatening to collapse the bank, spilling foreign material into the river. A long term stabilization and restoration plan is needed to reduce sedimentation and create habitat diversity in this stretch of river.   The NPT, partnering with NRCS, will subcontract a design firm to provide a design and cost estimate for restoration at this site along the South Fork Clearwater River mainstem.  The design and accompanying Basis of Design Report will aid in the development of environmental compliance documentation as well as an overall cost estimate and restoration schedule to prepare for future implementation. Special care will be taken to include fish-friendly design features to enhance this portion of river lacking habitat diversity while also reducing or eliminating a significant sediment point source.  This project, when implemented, will benefit the habitat of all anadromous and resident fish species in the mainstem South Fork Clearwater River, including steelhead, spring/ summer Chinook, and fall Chinook by reducing instream sediment and providing habitat diversity along this stretch of river.

The NPT and the NPCNF also propose to replace Forest Trail #385’s ford at Mill Creek with a bridge and hardened approaches to improve habitat for the anadromous and resident fish populations by increasing cover and stream depth and reducing the turbidity and physical disturbance caused by forest visitors. The current, unimproved crossing has created ongoing erosion which has increased sediment in Mill Creek, compounded by the adjacent campground, negatively affecting anadromous fish spawning and rearing habitat. The NPCNF has secured funds for most, if not all, of the design work for FY 23 and the NPT will provide design review and future partnership of the implementation.

Finally, the NPT and Bureau of Land Management (BLM) will work collaboratively with a subcontractor to provide design updates to a future restoration site on the South Fork Clearwater River mainstem that was previously designed in FY 19. The engineering firm will be subcontracted to assess less aggressive alternatives while still achieving the same fish habitat restoration objectives.  The NPT will administer the subcontract with the engineering firm and both agencies will participate heavily in design review.  The BLM will complete the NEPA requirements for the future restoration project.  Both BPA and SRBA funds will be applied to this subcontract.

In FY 23, work also includes fence maintenance along with continued planning and coordination for next year's projects and out-year habitat improvements. Pit tag arrays will be maintained as they monitor fish passage through a suspected partial velocity barrier site in the South Fork Clearwater River in preparation for a potential velocity barrier removal project in partnership with the NPCNF in out years.