International St. Mary and Milk Rivers Study Board Announces Extension


The International St. Mary and Milk Rivers Study Board has received an extension of up to one- year from the International Joint Commission (IJC) to complete its work. The study board will now provide its final report to the IJC no later than June 2026.

The extra time will allow the study board to fully consider the results of its technical work and input from its public, Indigenous, and governmental advisory groups.

The St. Mary and Milk Rivers Study was launched in 2021 to examine approaches and options that could improve access to the apportioned waters of the rivers between Canada and the United States. This is in recognition of the challenges that have emerged since the IJC issued its Order in 1921, and the potential effects of climate change moving forward. As part of its work, the Study Board is looking into the effectiveness of structural and non-structural options, and combinations thereof, that may impact apportionment. These efforts rely on technical expertise from people in both countries and the Indigenous Tribes and First Nations in the basin.

The St. Mary and Milk Rivers are connected by the St. Mary Canal, which moves water from the more sustainable flow of the St. Mary River to the naturally ephemeral Milk River. These waters are split, or apportioned, between Canada and the United States under the provisions in the 1909 Boundary Waters Treaty and in the IJC’s 1921 Order. The water flow is measured at the border and the amount available to users in each country is calculated according to the guidelines used by the federally appointed Accredited Officers.


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Paul Allen  Canadian Section             (613) 222-1475

Ed Virden  US Section                (202) 372-7990

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