Chapter 19 - Nelson and Churchill River Basins

Abstract

The Nelson and Churchill river basins together cover 1,353,600km2 of North America, encompassing a great diversity of elevations and physiography and draining parts of four provinces and four states. Made up of seven main drainages—Churchill River, North and South Saskatchewan rivers, Assiniboine River, Winnipeg River, Red River, and Nelson River—water begins in the Rocky Mountains and forested uplands and later passes through the Great Plains, the Saskatchewan River Delta, and Lake Winnipeg, the world's 11th largest lake, en route to Hudson Bay. Here we cover seven rivers that range from small creeks in the mountains (Sibbald Creek) and prairies (Smith Creek) to medium-sized rivers draining mountains (Bow River), forests (Beaver River, Otter Tail River), and fields (Qu’Appelle River) and a small stretch of river connecting two large lakes (Dauphin River). The southern portion of the Nelson is Canada's most water-stressed region, with flooding and drought common and a large proportion of the surrounding landscape lacking surface water connections from geographically isolated wetlands. Major anthropogenic stressors in the basins include agriculture in the south and forestry in the north, with hydroelectric dams regulating flow throughout.