Description:
A stream channel survey and modified R1/R4 inventory was completed throughout the project reach to identify potential limiting factors to the trout population. It was determined that severely eroding stream banks, lack of cover, high stream temperatures and the presence of non-native fishes negatively influenced the utilization of this section by Yellowstone cutthroat trout. A HEC-RAS model was completed for the project reach to identify areas of suitable velocities to maintain constructed pool depths through scour. Pre-design research indicated historic mining and the presence of selenium in the watershed. Prior to construction, selenium samples were taken throughout the project reach to determine if the project would result in negative impacts to water quality. All results came back negative and the project was approved by the DEQ. Downstream sediment inputs were a concern during construction. A temporary diversion structure at the head of the project reach was used to divert flows around the project and reduce the potential for downstream sedimentation. A total 3,100 linear feet of bank stabilization, 9 pools, 5 point bars, 1 vortex weir and 100 transplanted willows were installed in 2004. In 2005, the remaining plants, including sedges, rushes and willow cuttings, were installed after the peak flow event.