St. Joseph River near Newville in DeKalb County, Indiana.Floodwall along St. Joseph River in Fort Wayne, Indiana.
The St. Joseph River (Miami-Illinois: Kociihsasiipi)[1] is an 86.1-mile-long (138.6 km)[2] tributary of the Maumee River in northwestern Ohio and northeastern Indiana in the United States, with headwater tributaries rising in southern Michigan. It drains a primarily rural farming region in the watershed of Lake Erie.
The St. Joseph River of Lake Michigan is an entirely separate river that rises in western Michigan, dips into Indiana, and flows west into Lake Michigan.
Origin
At the end of the Wisconsin glaciation, the glacier's Erie Lobe retreated toward the northeast, leaving large debris deposits called moraines. The St. Joseph formed as a meltwater channel between the north limbs of two of these moraines, the Wabash Moraine on the west and the Fort Wayne Moraine on the east. At that time it joined the St. Marys River to drain into the Wabash River. Later, the shrinkage of Glacial Lake Maumee, the ancestor of modern Lake Erie, brought about the opening of the modern Maumee River, which captured the flow of the St. Joseph and the St. Marys, causing the St. Marys to reverse its course to meet the flow of the St. Joseph almost head-on.
