Water resources of the Rainy Lake watershed, northeastern Minnesota

The watershed includes 1,481 lakes that are 10 acres (4 square hectometers) or larger (Minnesota Division of Waters, Soils, and Minerals, 1968). The area of these lakes total about 435,000 acres (176,000 hm²) or 15 percent of the watershed. Most of the lakes are smaller than 250 acres (101 hm²) (graph); data pertaining to selected large lakes are given in the table below.

More than 60 percent of the lakes larger than 10 acres (4 hm²) are in the BWCA. The primitive character of the BWCA is maintained in accordance with the Wilderness Act of September 3, 1964. Most lakes not in the BWCA were assigned a Public Waters Classification by the Minnesota Department of Natural Resources, based upon the suitability of the lake for future shoreland development (unpublished data from the Minnesota Department of Natural Resources). “Natural environment” is most restrictive and “general development” least restrictive with respect to development standards. About 80 percent of lakes classified in the watershed have been designated “natural environment.”