Many Island Lake

Water Survey of Canada - 05HA

History and Overview

The Many Island Lake sub-watershed straddles the Alberta/Saskatchewan border and extends north from Cypress Hills to the hamlet of Schuler. Bordered on the northwest by the SSRC sub-watershed and on the southwest by the Seven Persons Creek sub-watershed, the Alberta portion of this sparsely-populated sub-watershed lies entirely within Cypress County.

The Many Island Lake and Pakowki Lake sub-watersheds are considered closed basins, which generally do not contribute runoff to the main river system. A number of creeks on the north slope of Cypress Hills drain into Many Island Lake including Mackay Creek, Boxelder Creek, and McAlpine Creek which has been recognized as a provincially ranked Environmentally Significant Area (ESA). Boxelder Creek crosses provincial boundaries and is managed under the Master Agreement on Apportionment between Alberta and Saskatchewan.

Variable, but permanent, lakes within the sub-watershed include Chappice Lake, a groundwater-fed saline lake that provides globally significant waterfowl habitat and critical nesting habitat for vulnerable, endangered or threatened grassland birds. Many Island Lake has been identified as a national level Environmentally Significant Area (ESA) and has been protected as a provincial bird sanctuary since 1917. Sam Lake has also been recognized as a biophysically important ESA for its bird habitat value, native prairie, priority plant species, wildlife habitat and extensive saline springs and seepage.

Ducks Unlimited Canada opened its first office in 1938 and its first task was to investigate Many Island Lake.

Risks and Pressures

The lake was drying up as a result of an increased demand on inflowing creeks from settlements compounded by the drought of the 1930s. By 1936, its water level fell to such an extent that closure of the sanctuary was considered. As one of its first wetland restoration projects in Canada, DUC built a dam at the outlet, which raised the level and restored waterfowl habitat.