Rattlesnake Creek Fish Screen Project

Project Date: 2015-2016


Partners: MT Fish, Wildlife, and Parks Future Fisheries Improvement Program, WSCTU, U.S. Fish and Wildlife Service.


Located right near Missoula, Montana, the Hughes-Fredline ditch is one of the few unscreened diversions on Rattlesnake Creek.


Each year, it is known to entrain hundreds of juvenile fish, including threatened bull trout. This ditch is mostly known as a “backyard stream” to many local residents, who find stranded fish in their backyards each fall.


When the ditch is initially diverted from Rattlesnake Creek, it flows through the Tom Green Park in Missoula  providing important spawning habitat. Since Rattlesnake Creek has become increasingly channelized with urban development it no longer exhibits braided side channels and during irrigation season, fish access is limited.


As the Big Sky Watershed Americorps member with the National TU team at the Missoula office, it was my pleasure to take on this riparian restoration project, upgrading the Hughes-Fredline irrigation diversion on Rattlesnake Creek and making it fish-friendly.


We worked with Missoula County, private landowners, and water users to create a design that allowed water users to continue to receive their allocated water rights while eliminating fish entrainment and improving fish access to the spawning habitat. To achieve this, we created a new bypass channel, installed a Coanda-style fish screen on this channel, and piped the screened irrigation water. We also installed a head gate at the diversion inlet to allow for improved water control and functionality of the fish screen.


With the increasing subdivisions and urbanization of Rattlesnake Creek, it is important to preserve spawning habitat and reduce loss of fish down diversions. TU plans to work with the Missoula Conservation District over the next few years to upgrade screens on other irrigation diversion throughout the lower Rattlesnake as many of these are reaching the end of their functional lifespan.


This project was made possible by funding through MT Fish Wildlife and Parks Future Fisheries Improvement Program, the West Slope Chapter, and U.S. Fish and Wildlife Service.


View original blog post: http://www.tu.org/blog-posts/fixing-missoulas-backyard-stream


Below photos by Molly Barth: