Swan Lake covers an area of, with an average depth of, giving a contained water volume of. There is a large marsh complex along the west shore of Swan Lake, near the Swan and Woody Rivers, which is a significant area for migrating birds in the region. The Swan Lake drainage basin covers and extends into the province of Saskatchewan. It is located between the Duck Mountains and the Porcupine Hills. Two major rivers discharge into Swan Lake from the basin, the Swan River and the Woody River. Other topographic features include Thunder Hill, the Swan River valley and plain, the two river's many tributaries, and Swan Lake and its surrounding deltawetland area. In addition to Swan Lake, there are approximately 30 smaller lakes in the basin; the major ones being, Lac La Course, Madge Lake, Sarah Lake, Wellman Lake, Whitefish Lake and the Woody Lakes. Land elevations vary from 2,600 and 2,300 feet above sea level in the Porcupine Hills and Duck Mountains respectively, to 851 feet above sea level at Swan Lake. The Porcupine Hills and Duck mountains are forested, as was the majority of the remainder of the basin originally. Explorer Thomas Simpson remarked when traveling through the area in 1837: Much of the forest has since been cleared and replaced with agriculture. The area also supports significant forestry, hunting, sport-fishing, tourism and outdoor recreational activities. Currently 42.7% of the basin is forested, 38.4% is devoted to agriculture, 15.5% is surface water, with the remaining 3.4% unclassified. Wetlands occupy 10% of the basin, mostly bogs and shallow ponds located in the headwater areas of the Duck Mountains and Porcupine Hills, as well as the Swan Lake marsh complex. Average annual precipitation in the basin is 19 inches. Frost free period ranges from 87 to 110 days. The basin's average annual discharge is approximately. Of that, up to of water per day are free for domestic use without a water rights license. Less than of annual water rights licenses have been approved. Total population living in the basin is approximately 14,000, the largest component consisting of approximately half of the total being rural residents living outside of major communities. The only communities on the lake itself are the main reserve of the Wuskwi Sipihk First Nation and the northern part of the Rural Municipality of Mountain, both on the lake's western shores. The largest community in the basin is Swan River, Manitoba, with a population of 4,032. The remaining communities with the exception of Minitonas, have fewer than 500 residents. These communities are: In Saskatchewan:
