Key Issues
The Milk River watershed is a small, semi-arid and trans-boundary watershed. Climate in the Milk River watershed is unique in comparison to the rest of Alberta. The semi-arid environment has influenced not only the soils, vegetation and wildlife that are found there, but it has also shaped the people, industry and economic growth in the region.
View Bedrock Geology 307 KB JPG
View Landcover 544 KB JPG
View Plains Cottonwood Distribution 248 KB JPG
View Native Prairie Vegetation 282 KB JPG
View Landscape Management Units 298 KB JPG
View Spadefoot Toad 268 KB JPG
View Great Plains Toad 239 KB JPG
View Pintail Breeding Density 302 KB JPG
View Invasive Species 246 KB JPG
View Wetland Density 295 KB JPG
VIew Wetland Inventory 738 KB JPG
View Milk River Reaches and Fishes Distribution 633 KB JPG
View Historical Resource Sensitivity Types 407 KB JPG
View Historical Resource Values 292 KB JPG
View Oil and Gas Activity 330 KB JPG
View Parks and Protected Areas 296 KB JPG
Water Supply and Management
The water in the Milk River comes from snow-melt in the headwaters, inflows from tributaries and precipitation runoff throughout the watershed. Snow-melt in the headwaters accounts for between 50% and 80% of the water in the river. Precipitation runoff accounts for the remaining 50% to 20% of the water in the river. In addition to the natural flows, the water in the Milk River is augmented by an inter-basin transfer of water from the St. Mary River. The St. Mary Canal, completed in 1917, carries water from the St. Mary River to the North Milk River, just before it flows into Canada. This inter-basin transfer allows the U.S.A. to use its share of the water in the St. Mary River system, which originates in the U.S.A., but flows into the South Saskatchewan River Basin. The canal usually operates from April to October, transferring from 17 to 21 cubic meters of water per second.
Water supply and management has always been a concern in the Milk River watershed. Water management dates back to the Boundary Waters Treaty of 1909. The Treaty established the International Joint Commission (IJC), made up of members from both Canada and the United States, for the purpose of resolving disputes. In 1921, the IJC created the Order that outlines how water is apportioned (shared) and measured in the St. Mary and Milk Rivers.
During the irrigation season, the U.S.A. is entitled to three-quarters of the flow in the Milk River and Canada is entitled to one-quarter of the flow, up to 666 cfs. The U.S.A. is entitled to one quarter of the flow in the St. Mary River and Canada is entitled to three-quarters of the flow. In the non-irrigation season, the flows are divided equally for both rivers.
Water management discussion are still underway regarding the Milk River and St. Mary systems as the International Joint Commission reviews the 1921 Order with the support of a Task Force made up of three Alberta representatives and three Montana representatives. Recently, the Task Force developed recommendations for the IJC to consider in their review.
The Milk River Watershed Council Canada will strive to work closely with Montana and Saskatchewan in watershed management planning and land stewardship initiatives. The MRWCC would like to maintain good working relationships with watershed neighbours by creating a process and forum to address trans-boundary watershed concerns.
Real-time flow data for the Milk River can be viewed at the Water Survey of Canada.
Water Quality
One of the goals of the Milk River Watershed Council Canada is to gain a better understanding of water quality in the Milk River watershed by monitoring the river and its tributaries. Groundwater quality monitoring is also essential to understand the resource and how it influences human health. The MRWCC will promote quality domestic water supplies in the watershed and make information available to residents, agencies and industry living and working in the watershed. Refer to Projects in the menu above to learn more about our monitoring programs.