The Lake Simcoe watershed sweeps across 3,400 square kilometres and 20 municipal borders. The lake itself covers 20 percent of the area and provides a source of safe drinking water to seven municipalities. There are over 400,000 residents in the watershed; 18 major river systems; 4,225 kilometres of creek, stream and tributary channels; and it's home to 75 species of fish, with over 50 in the lake alone.