Lower Swift Creek Flow Restoration
Swift Creek, a Salt River tributary in Star Valley, experiences significant impairments from top to bottom, including a hydropower dam, dewatering, and channelization in upstream areas, and sediment transport issues and bank and channel instability in lower reaches. TU, the Natural Resources Conservation Service, Wyoming Game and Fish Department, US Fish and Wildlife Service, and many more partners are working with private landowners to restore natural hydrology, fish habitat, stream function, bank stability, floodplain connectivity, and riparian vegetation on lower Swift Creek while also preventing the loss of about 800 feet of spawning habitat important to the Salt River’s blue-ribbon cutthroat and brown trout fishery.
Landowners in lower Swift Creek have been actively seeking a collaborative solution to address sediment, stream stability, and fish habitat issues since 2012. They have experienced extreme channel instability, bank erosion, downcutting, aggradation, loss of pasture, issues with flooding, and difficulty maintaining agricultural activities, even following improvements to grazing practices adopted about 20 years ago. All of these issues are symptoms of an unstable stream with sediment transport out of balance. By restoring a functional stream pattern and profile, stabilizing the channel and banks, and revegetating the riparian zone, TU and its partners believe that lower Swift Creek can achieve a new stable state in a relatively short time frame, which will restore a natural hydrology to the lower half of the project area (by reconnecting the stream to its floodplain) and greatly reduce the risk of channel abandonment and fish habitat loss. The project’s goals are to 1) protect, improve, and increase spawning cutthroat trout habitat; 2) reduce sediment contributions to the Salt River by 64% (66,000 ft^3/yr to 24,000 ft^3/yr), thereby improving water quality; and 3) reduce landowner pasture loss, flood risk and maintenance requirements. Successful treatments on Swift Creek can be used in the future as a model to address similar issues in the upper Salt River.
Recent research has determined that mountain tributaries connected to the mainstem Salt River, like Swift Creek, and restored spring creeks are where the majority of spawning occurs for the Salt River Snake River cutthroat trout population. By protecting existing (and creating new) spawning and rearing habitat, this project will contribute to the future persistence of native cutthroat in the Salt River watershed by maintaining and improving spawning recruitment from lower Swift Creek and restoring a natural hydrology to the lower half of the project area.
* Project restores natural hydrologic conditions to facilitate improved capture and infiltration of surface water and groundwater recharge