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River Rendezvous Tours St. Mary Diversion

On June 27th, the Milk River Watershed Alliance and Missouri River Conservation Districts Council hosted the 2017 River Rendezvous that toured the St. Mary diversion system which supplies 60-90% of the water in the Milk River. The tour had two options, the international tour which viewed Alberta’s St. Mary irrigation systems and constructed wetlands in the Milk River Ridge Reservoir, which then met up with the Montana tour group who viewed the St. Mary diversion system near Babb, MT. The tour was open to the public and brought in over 60 participants from Conservation Districts, MT DNRC, Senate and Provincial Parliament representatives, landowners, local businesses, economic growth councils, and members of various watershed groups.

The Canadian tour viewed the St. Mary Diversion Dam, which was funded entirely by provincial government in the 1990s when they decided to rebuild the spillway to ensure the longevity of the structure.  The first diversion dam was constructed by the Prairie Farm Rehabilitation Administration (PFRA) during 1949-51. The PFRA was created in the 1930s by the Canadian government to drought proof the prairies by creating reservoirs for irrigation and municipal use. Today, 400,000 acres are irrigated from the St. Mary Project from Lethbridge to Medicine Hat. A hydropower facility downstream from the diversion dam is able to produce enough electricity for three electric districts. The tour also viewed the Milk River Ridge Reservoir, which contains collaborative projects aimed at improving water quality through fencing, tree and shrub restoration, phosphorous filtering, installing livestock watering systems, corridor widening, and shelter belts.

The Montana tour viewed the 100-year-old diversion system that was one the Bureau of Reclamation’s first five projects to be authorized in 1903. The Milk River Project, which starts with the Sherburne Dam in Glacier, was intended as a single purpose project for irrigation water supply. The St. Mary diversion system consists of a storage dam, diversion dam, head gate, 29 miles of canal, two sets steel siphons carrying about 300 cfs each, and five concrete drop structures. The Milk River Project provides irrigation for 110,000 acres on 660 farms. The towns of Havre, Chinook, and Harlem utilize the Milk River as their municipal water supply for about 14,000 residents. Other beneficiaries include fisheries and wildlife, sportsmen, recreationists, local businesses, and tourism. The diversion system has seen only minor repairs, when a complete rehabilitation is needed. The current rehabilitation costs are around $200 million, and the cost allocation is broken down 75:25. 75% of the cost is allocated to the irrigators on the Milk River Project, and 25% to the US Bureau of Reclamation, an unfeasible ratio for a project of such magnitude and economic impact. The purpose of the tour was to shed light on the critical need for rehabilitation, the benefits of the Milk River and impacts on local communities and agriculture, while highlighting the drastic and impractical cost allocation upon the irrigators.  The Milk River Watershed Alliance is a locally led group of Conservation Districts working together to protect, preserve, and enhance the natural resources within the Milk River watershed, while maintaining the quality of life.


Kate Arpin

Kate is the Communications and Technology Manager for Soil & Water Conservation Districts of Montana. She manages the website, puts out The Montana Conservationist every other week, and assists conservation districts with technology, websites, and communications.

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