Managing Eurasian Watermilfoil in the Lower Clark Fork River Danny MacKay Natural Resource Technician Avista Utilities Sanders County June 17, B Noxious

Fall 2007: Formation of the EWM Task Force June 17, 2007: EWM confirmed in Noxon Rapids and Cabinet Gorge Reservoirs Summer of 2008: Mapping EWM infestations in Sanders County Summer 2008 – Spring 2009: Phase 1 EA Completed. U.S. COE partners with the project. First bottom barrier installation. May 2009: Education Coordinator starts work. July 2009: First Dye/Herbicide Trials (40 ac) Spring 2010: Phase 2 EA completed July 2010: Phase 2 Dye/Herbicide Trials (33.1 ac) July 2012: Pre-treatment monitoring August 2012: Herbicide treatment (174 ac) Project Timeline 2011 high water year

Aquatic Invasive Plant Task Force – Avista Utilities – MSU Extension/Sanders County – Noxon Cabinet Shoreline Coalition – Green Mountain Conservation District – Montana Bass Federation – Private industry representative – At-Large Sanders County resident – Confederated Salish & Kootenai Tribes – Sanders County Weed District – Montana Department of Agriculture – MT Fish, Wildlife, & Parks – U.S. Forest Service – PPL Montana

AIP Task Force Goals Effectively manage Eurasian watermilfoil Reduce the risk of spread of this plant and other aquatic invasive plants Implement an aggressive Integrated Weed Management Program on the two reservoirs Post-Treatment Eurasian Watermilfoil with healthy Elodea from the same rake pull.

Working Together Good Connection Mixed group of Stakeholders with majority of them being local Local stakeholders have local interests Project Support National expert advisory Public Process Education and Outreach Pre-treatment test trials Funding

Project Funding $1.2 million - total project cost so far (includes 2013 plans) $250,000 – Avista contribution ( Includes efforts with barriers, education, herbicide and check stations.) Funding sources / Partners Sanders County Noxious Weed Trust Fund National Fish and Wildlife Foundation Montana Department of Agriculture Idaho Department of Agriculture Noxon Cabinet Shoreline Coalition Avista Utilities MSU Extension Mississippi State University U.S. Forest Service Confederated Salish & Kootenai Tribes Montana Fish Wildlife and Parks Green Mountain Conservation District U.S. Army Corp. of Engineers (Stimulus / reinvestment funds) Montana Department of Natural Resources and Conservation

Herbicide Test Trials acres acre plots were treated. Dye was mixed with herbicide to track movement. Treatment plots were compared to control plots acres 3 smaller plots were treated. Dye was mixed with herbicide to track movements.

Bottom Barrier Program Constructed of gas- permeable, negatively buoyant fabric and sand filled PVC piping. Help prevent fragmentation from boats near docks. Divers place barriers on the reservoir bottom to inhibit weed growth. Ground crew handing off a bottom barrier for the diver to install.

Boat/Trailer Check Stations Noxon Rapids and Cabinet Gorge Reservoirs form a legally designated "special management area" with three mandatory watercraft check stations. Montana Dept. of Agriculture Program. 12 hour per day. Operate from Memorial Day to Labor Day. Eurasian Watermilfoil Lower Clark Fork Management Area LocationOperation Days Total Inspections Non-Res. BoatsMT BoatsRe-certificationsDrive-bysContaminated Boats Troy Junction of Hwy 200 & Hwy Plains

Education Coordinator Booths: Huckleberry Festival, Sanders County Fair, Mayfly Fling, Sanders County Water Festival One on One contacts with boaters and fishermen. Assist AIP Task Force with treatment phase Education coordinator at the Mayfly Fling in Missoula, MT

2012 Herbicide Treatment 174 acres of high priority sites were treated in Noxon Rapids Reservoir. Herbicides: Endothall, Triclopyr and Diquat. Deep water injections to allow herbicide to penetrate the thick EWM stands. Clean Lakes applying Herbicides in Noxon Rapids Underwater view of dual release herbicide nozzle

Future Plans 2013 – week after herbicide treatment survey/2013 pre- treatment survey. – Treat ~ 200 acres of EWM in Noxon Rapids Reservoir and possible Cabinet Gorge Reservoir. – Six week post treatment survey Future – week after herbicide treatment survey – Treat remainder of Cabinet Gorge Reservoir – Reduce EWM in the management area to a “maintenance scale” (e.g. diver pulling, low scale herbicide treatments, bottom barrier control)

Contact Information Danny MacKay Natural Resource Technician Phone: (406)