The drainage area of the Roseau River consists of 2,060 square miles above its confluence with the Red River of the North. About 1,150 square miles lie in the United States and 910 square miles in Canada. This report deals only with that portion within the United States, except for a detailed analysis of low flow characteristics of tributary streams.

Most of the area is within Roseau County, but small portions are in Marshall, Beltrami, Lake of the Woods, and Kittson Counties. Most of the watershed has little relief, and lies entirely within the plain of former Glacial Lake Agassiz. However, the flat topography of this lake washed till plain is broken by beach ridges in its southwestern part and Beltrami Island, a topographic high underlain by sand, in tis southeastern part.

Population within the watershed is about 8000. The town of Roseau, the largest community, has a population of 2146 (1960).

The watershed has an agricultural economy. Spring wheat, oats, and bluegrass seed are the three most important crops in the area, but many other small grains, legumes, and grasses are also grown. Dairy farming and sheep raising are the most important types of livestock production and for many farms stock is the major sources of income.

Large areas of the watershed are peat lands, covered with shrubs, marsh grasslands, and spruce, tamarack, and cedar trees. Forest vegetation in the remainder of the area is largely aspen, but oak is common on the beach ridges and jack pine is common on Beltrami Island.

Outdoor recreation in the area is primarily hunting of deer, small game, and waterfowl.

This report is a general appraisal of the water resources in the Roseau River watershed unit. Detailed studies of water movement through the ground-water reservoir are needed for more exact determination of the amount of water immediately available and the specific effects of water-management practices.