Mill Creek Watershed Fine Sediment Abatement - Hoopa Reservation

Fine sediment inputs from upslope areas can impact stream health and fish redd success. Flood events, combined with past land management activities conducted by the Bureau of Indian Affairs and naturally occurring landslides, resulted in many failed road systems which altered stream channels and riparian areas and negatively impacted spawning and rearing habitat. While practices have improved significantly and substantial habitat recovery has occurred, there are still problem sediment sources and instream habitat deficiencies that are likely limiting recovery. In 2016 Hoopa Fisheries and Pacific Watershed Associates completed a watershed assessment for the Mill Creek Drainage to catalog those potential sources of fine sediment and finalized the report in 2017. An outcome of that assessment was a prioritized list of issues to address to prevent fine sediment from stream crossings, landslides and relief culverts.



This project proposes to address five of the stream crossings listed in the aforementioned Watershed assessment. A few examples of actions to address these crossing could include culvert repair and replacement, rebuilding water bars, redirecting of water from the road to vegetated areas. All selected treatments to address stream crossing will follow the recommended prescription for treatment in the watershed assessment. These protocols are described in the California Salmonid Stream Habitat Restoration Manual, Chapter 3 (CDFG, 2010).

Address fine sediment impacts identified in the 2017 Mill Creek Watershed Assessment funded by FRGP. : SONCC in the lower Trinity River are identified in the Recovery Plan as being at high risk of extinction. Restoration of tributary habitat for both natal and non-natal SONCC is therefore of great importance. Mill Creek provides year-round flows of cool water into the Trinity River. Both non-natal and natal juvenile SONCC as well as adults utilize Mill Creek. The lower reaches of this stream have been the recipient of large scale restoration efforts including an 11 acre floodplain expansion and channel realignment with multiple ponds and other off channel features. This proposed project is expected to support increases in survival and growth of Coho as well as the other native anadromous salmonids.



Priority One – Priority One projects habitat improvement projects. The PCSRF Program is focusing particular emphasis on habitat improvement projects that achieve lasting benefits through the restoration of self-sustaining natural ecosystem functions and processes.