The
Souris River or
Mouse River (as it is alternatively known in the
U.S.) is a river in central
North America. It is about 700 km (435 mi) in length and drains about . It rises in the Yellow Grass Marshes north of
Weyburn,
Saskatchewan. It wanders south through
North Dakota beyond
Minot to its most southern point at the city of
Velva, and then back north into
Manitoba. The river passes through the communities of
Melita,
Hartney,
Souris and
Wawanesa and on to its confluence with the
Assiniboine River at
Treesbank, about south east of
Brandon. The main tributaries which flow into the Souris in
Manitoba are the Antler River, the Gainsborough and Plum Creeks. Much of its drainage basin is fertile silt and clay deposited by former glacial
Lake Souris.