The Mississinewa River is a tributary of the Wabash River in eastern Indiana and a small portion of western Ohio in the United States. It is about 100 mi long.  Near its mouth in Miami County, a U.S. Army Corps of Engineers dam causes the river to form Mississinewa Lake. The dam was built for flood control in 1967.  Mississinewa Lake has 3180 acres of water in the summer for fishing, boating, swimming and other water related activities.  The lake is located in Wabash, Miami, and Grant counties in north central Indiana.