Rattlesnake Creek Passage Project (aka Rattlesnake Removal) by

Objectives

1. Eliminate all upstream aquatic barriers 2. Prevent entrainment of salmonids at all diversion sites 3. Reconnect Rattlesnake Creek to the Clark Fork 4. Improve recreational access

Completed Activities

• Topographic Survey of all diversions • Conceptual design for improved diversion structures and fish screens at all sites • New fish screens installed on 3 of 6 diversions • New streamflow gauge installed • LiDAR flight completed for Rattlesnake Dam • Preliminary data collection completed for Rattlesnake Dam

Rattlesnake Dam

Sketch showing system, showing Rattlesnake Lakes, Creeks and Reserviors. 1931

Map of Rattlesnake Creek and Various Ditches. 1926 RW-2: Topo Map of Rattlesnake dam site in Rattlesnake valley. C.1900 Men Sitting at Rattlesnake Dam – c.1900

Waterworks Dam, Rattlesnake Intake. 1914

Reservoir and additional land required. 1924

Improvements at diversion dam; preliminary sketch. 1924

Vision

• The City of Missoula, Trout Unlimited and Montana Fish, Wildlife and Parks are invested in the Missoula community and its stewardship of Missoula Water and Rattlesnake Creek. Since the lower Rattlesnake Creek Dam has been determined to be inoperable and non-essential, mitigating and restoring the dam site has the potential to restore habitat for native fish and terrestrial wildlife, improve water quality in Rattlesnake Creek, reduce maintenance costs and provide additional scenic open space and recreational opportunities for the Missoula community. Therefore, the City, MFWP and TU desire to work collaboratively to plan and implement a restoration project at the dam that will remove existing man-made infrastructure and re-naturalize the site. Following restoration of the site the land will be managed as City public Open Space in conjunction with the greater Rattlesnake Greenbelt system of Conservation Lands.

City Property Boundaries Funding to Date

• Northwestern Energy - $33,125

• Montana Future – $24,000

• Westslope TU Chapter - $35,000

• Montana Trout Unlimited – $10,000

• Missoula Conservation District $10,000

• Stockman’s Bank $10,000

• Other grant sources - $85,000

• TOTAL - $207,125

Rattlesnake Dam Timeline

• LiDAR/Phase I Data Collection - Fall 2017 • Conceptual Design - Winter 2017 • Public scoping and review - Winter/Spring 2018 • Data collection Phase II - Summer 2018 • Permitting - Fall 2018 • Final Design and contracting - Winter 2018 • Construction Phase I - Summer 2019 • Construction Phase II - Summer 2020 • Monitoring - Summer 2021 Anticipated Results

• 25 miles of Rattlesnake Creek fully reconnected • 2,000 feet of new side channels created • 6 irrigation diversions fully screened • 1,000 feet of stream channel restoration • 4 acres of wetland restoration/rehabilitation • 40 acres of trails and open space • $$ (thousands) in annual maintenance and operations at Rattlesnake Dam