South Fork Little Butte Creek RM 6.8 - Ecological Restoration Project

This project is the first phase of multi-year actions throughout Little Butte Creek. The sub-basin has degraded water quality, stream processes, and aquatic and terrestrial habitats that negatively affect ecosystems, including plant and animal populations. Riparian forests are reduced, grazed, and infiltrated with noxious weeds, unimpeded livestock access to the creek increases sedimentation and nutrient loading, and simplified channels and large wood removal eliminate channel complexity, aquatic habitat creation, and floodplain interactions. These cumulative impacts also elevate summer water temperatures, threatening cold water fish populations. The project proposes restoration actions that will result in significant ecological uplift at these locations. This will be accomplished placing large wood at strategic locations throughout the project length. Additionally, a combination of large wood placement and channel excavation will re-activate a section of secondary channel and increase frequency and duration of winter inundation. Riparian rehabilitation activities to recover the native plant community will involve noxious weed control, building livestock exclusion fence, and planting of native nursery stock. Plant stewardship activities (reported as C.11 - Site Maintenance) will be conducted for up to five years after the plantings are completed. These stewardship activities, consisting of mechanical and chemical noxious weed control and watering, will ensure the success of the project plantings by helping plants achieve free-to-grow status.

Because the projects scheduled end date is after the PCSRF FFY 2019 award closes, all PCSRF funds will be expended prior to the award closure date and only State and Other funds will be used after that date. No funds allocated for this project are reported as match to PCSRF funds.

The location of this project is important due these factors: entry of a cool-water tributary near the upstream end of the project, proximity to colder water habitat upstream, a wide valley width with lateral channel migration, and observed active redds during design surveys at a time when Coho Salmon and Steelhead spawn. Although temperatures occasional exceed regulatory targets for salmonid rearing, they are within the range that restoration actions upstream and downstream will have positive effects on juvenile salmonid survival and fitness. Part of the long-term strategy is to build contiguous ecological restoration projects that will reduce critical summer rearing temperatures into the optimal biological range throughout the entire South Fork Little Butte Creek drainage. This project is focused at a low gradient stream segment in an unconstrained valley with an existing native overstory forest. Large wood placement can increase available spawning gravel, reduce substrate embeddedness, increase pool and riffle formation, lower water velocities, and increase nutrient and water exchanges with hyporheic flow and groundwater. There are also aquatic habitat improvements for fish cover and resting areas, spawning and rearing, and invertebrate production to increase food availability. Reactivation of the secondary channel will increase usable habitat during winter flows that are key for juvenile survival and fitness, particularly Coho Salmon that thrive in near zero velocity habitat. Alcove development at the downstream end of the secondary channel location will be accomplished with a combination of large wood and channel excavation, providing year-round access for juvenile rearing opportunities. With the recovery of the native riparian plant community, allochthonous inputs provide essential few web interactions, increase aquatic invertebrate communities, and provide food sources for salmonids. The riparian forest will also provide a long-term buffer on lower water temperature and higher water quality such as reduced erosion and nutrient input. There are a few areas on the project where increasing plants along the bank will reduce solar input and further buffer water temperature. Floodplain livestock exclusion fence will prevent trespass, improving water quality. The restoration actions together will directly improve conditions that will benefit all salmonid life stages and support population growth.