Water resources of the Crow River watershed, south-central Minnesota

The Crow River watershed, an area of about 2,760 square miles, is covered entirely by glacial deposits. A topographically high, east-west-trending end moraine divides most of the watershed into two drainage areas of approximately equal size. The North Fork Crow River drains a mixture of glacial outwash and till deposits, whereas the South Fork Crow River drains chiefly till deposits. Local relief is greatest in morainal areas and least in surficial outwash areas.

Cambrian and Precambrian sedimentary rocks underlie the glacial drift in the eastern part of the watershed. Cretaceous sedimentary rocks, though discontinuous, are present in part of the western two-thirds of the watershed. Where sedimentary bedrock is absent, the glacial drift is directly underlain by Precambrian igneous or metamorphic rocks.

Forested areas are sparse and occur mainly in steeply sloping morainal areas. Most land is used for agriculture, and slightly more than half the total population is rural.