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 24, 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 24 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.  Fifteen BDAs were installed here in 2021 - 2023 per USFS small NEPA and permits, and more may be installed and maintained this coming year in 2024. BDA installation will also occur on private land on Sill Creek, a tributary to Sally Ann Creek.  This project installed four structures in 2023 along a 170 ft reach in partnership with the USDA’s Natural Resource Conservation Service (NRCS) and the landowner; more BDAs may be installed and maintained, up to ten over five years, at this site.  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, a crossing replacement was designed on private land on Sally Ann Creek, just downstream of the Sally Ann Creek Culvert #2 owned by Idaho County which was designed in FY22. 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. Along with the crossing replacement, instream restoration between the two crossings was also designed, adding high flow relief channels and log structures to both alleviate the high stream flow velocities and provide instream habitat. The crossing will pass all aquatic organisms, including all life stages of anadromous and resident fish, while reducing sediment into the South Fork Clearwater River.  In FY 24, both the private and Idaho County crossings will be replaced along with the instream restoration connecting the two. The construction contract will be competitively bid and held by the NPT. This project is contingent upon award of additional funding from the Idaho Office of Species Conservation, and will be completed in partnership with the NRCS, the private landowners, Idaho County, and IOSC.

Another design project for future implementation was identified 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. Through site visits and discussions, the NRCS and NPT have expanded the restoration to a two miles stretch of mainstem river, encompassing the private land. The NPT, partnering with NRCS and OSC, will subcontract a design firm to provide a design and cost estimate for restoration at this two-mile site along the South Fork Clearwater River mainstem.  The  assessment, 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. Overwintering habitat for salmonids and lamprey will be developed as well as the floodplain reconnected when the project is implemented.

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  the design work, which began late in FY 23, and the NPT will provide design review and future partnership of the implementation again in FY 24 as the designs are completed.

In FY 24, 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.