The District is located in east central Missouri within the St. Louis Metropolitan Statistical Area (MSA) approximately 35 miles west of the City of St. Louis. The District currently protects 88 square miles in western St. Charles County. Incorporated cities within the District’s boundaries include the Cities of Wentzville, Foristell, Lake St. Louis, and O’Fallon, as well as the Villages of Flint Hill and Josephville. The District is traversed by Interstate 70, U.S. Highway 40/61 (currently being upgraded to Interstate 64), U.S. Highway 61, and the Norfolk Southern Railroad.