200752800 - Little McCormick Creek: Investigating Placer Mine Impacts to Streamflow Connectivity and Developing New Restoration Techniques

Sponsor: Trout Unlimited

Short description: TU plans to restore surface flow and fish habitat in one mile of Little McCormick Creek. By studying bedrock geology, groundwater flows, and placer disturbance, TU will develop assessment and restoration techniques that are transferable in the region

Location: Mountain Columbia province, Clark Fork subbasin

Budgets: FY08: $45,500 | FY09: $51,300

Primary species:
Resident: Westslope Cutthroat

Objectives

ObjectiveDescriptionSubbasin planStrategies
1a.Study groundwater and bedrock geology TU intends to use modern geophysics and groundwater monitoring to effectively create a map of groundwater disperal and berock geology. The assessmentwill be used to design a placer mine restoration project that will restore channel function and restore surface water connectivity. Data analysis and results of the project will yield useful information for other restoraiton practitioners and be communicated in a number of communication venues. There is no Clark Fork River Subbasin Plan.
1b.Restore 1 mile of stream Restoring 1 mile of Little McCormick Creek will protect an important population of westslope cutthroat trout, stabilize a known sediment producing stream, and serve as a demonstration project for similar efforts throughout the region. There is no Clark Fork River Subbasin Plan.
1c.Improve native fish populations Little McCormick Creek contains only westslope cutthroat trout and have a high level of genetic purity. The risk of extinction for westslope cutthorat in the drainage is high based on the lack of migratory componenent, due to stream dewatering, and clustering of populations in close proximity where a large scale disturbance could affect all populations. There is no Clark Fork River Subbasin Plan.
1d.Increase knowledge of placer mine restoration Placer mines have largely been ignored by the restoration community and, despite their significant impacts to fish and aquatic habitat, there is a lack of knowledge about the underlying hydrology and geomorphic disturbance. TU's project is an effort to introduce new knowledge about bedrock geology, substrate compostion, and groundwater movement and translate that knowledge into overarching concepts and restoration techniques that can be transferred to different geographic areas. There is no Clark Fork River subbasin plan
1e.Reporting and information dissemination TU will serve as the project lead and be responsible for project coordination, reporting and dissemination of results. Through pre and post project biological and physical monitoring, TU will document the effect of placer mine restoration on fish and macroinvertebrate populations, sediment reduction, and channel stability. Analysis of groundwater and surface flows before and after the project will yield useful information about the efficacy of groundwater retention sills on stream flow connectivity and will be applicable to other Tu projects in the Ninemile Creek drainage and throughout the Pacific Northwest. There is no Clark Fork River Subbasin Plan.

Narrative

Recommendations

  • ISRP: Unranked
  • Council: Not fundable
  • BPA: Not fundable