ROCKIES: BIGHORN RIVER. For decades, Montana’s Bighorn River has captured the essence of fly fishing for wild trout. Clear water, willing wild trout and undeveloped surroundings make a true American treasure which the Bighorn Alliance strives to protect. The Bighorn River Alliance works to protect, preserve and enhance the long-term health and viability of the Bighorn River recognizing its significance to the wild trout fishery, the agricultural community, and the Crow Nation through which it flows.
In 2020, the AFFTA Fisheries Fund gave a grant to the Bighorn River Alliance for research to identify and plan for restoration of four significant disconnected or low-functioning side channels on the Bighorn River in Montana.
PROJECT OBJECTIVES. Many historic Bighorn River side channels currently only flow during high water because they have lost most of their connectivity with the main channel. This loss of connection is mostly due to sediment deposition and vegetation encroachment at their entrances, such that the heads of the channels are too high and too densely vegetated to frequently carry water. As these side channel habitats are recognized as important contributors to the health of the Bighorn river fishery, a recent focus of the Bighorn River Alliance has been to explore the feasibility of their reactivation.
FINDINGS. Initially, dozens of channels were considered for detailed assessment, but many were immediately discarded due to poor feasibility caused by excessive perching, infrastructure complications, land use complications etc. Ultimately, a total of 30 channels were evaluated with 13 considered “top tier” and two, Juniper and Rattlesnake side channels, selected for a first phase of restoration implementation. During the summer of 2020 they were surveyed in detail and permit-ready designs are complete.
NEXT STEPS. The project is currently in the permitting phase, with construction slated for Spring 2021.The projects will reactivate 1,800 feet of channel length on Juniper Channel and about 1,100 feet on Rattlesnake Channel. Whereas the Juniper channel doesn’t carry water until river flows reach 2,900 cfs (cubic-feet per second) at present; with the proposed excavation work, it should activate at less than 2,000 cfs. Current activation flows on Rattlesnake channel are similarly about 2,900 cfs; excavation of its entrance should increase connectivity so that it will flow at around 2,200 cfs.
AFFTA MEMBERS actively supporting the Bighorn River Alliance include Adipose Boatworks, Patagonia, Simms, and Yeti. Learn more about the Alliance, their project, and lend your support.
