1949 Map of St. Clair Flats

About this map

Dickinson Island and Harsens Island anchor this intricate hydrographic survey of the sprawling river delta where the St. Clair River meets Lake ST Clair. The landscape is a maze of interconnected waterways, defined by deep channels like the South Channel and the winding Chenal A Bout Ronde. This 1937 topographical survey, published in 1949, captures the maritime character of the region before modern development reshaped the wetlands. Land use is concentrated along the narrow strips of dry ground, notably at Riverside and the prominent The Old Club at the delta's tip. Numerous highway labels, such as Hurlburt Hy and Snooks Hy, follow the natural levees and ridges like Muscamoot Ridge, illustrating how early transportation relied on the unique geometry of the marshland. The map also delineates the international boundary between United States and Canada, running through the open waters south of Gull Island.