Illinois, the river returns to its natural channel, winding its way to Momence, Illinois. This is the last section of the Grand Kankakee Marsh that has never been ditched. It is at Momence that the river crosses a limestone shelf, referred to as the Momence Dam. This natural feature's resistance to erosion created a blockage in the flow of the Kankakee River, backing up water and thereby creating the Grand Marsh that once covered . The dam's removal is part of the story of the draining the marsh. Beyond Momence, the river takes on a more traditional image, flowing across the rolling hills of Kankakee County. Will County The river enters Will County, Illinois, for only a short distance before joining the Des Plaines River. Here, in the Des Plaines Fish and Wildlife Area, the two rivers form the Illinois River for the journey to the Mississippi River. Political entities Indiana Because of the river's wide valley and historic great marsh, there are few towns on the river throughout the entire length of Indiana. Most towns are located either north or south, on high ground, just outside the marshes. Today, the marshes have been drained and it is not apparent why the towns are so far from the river. St. Joseph County Greene Township South Bend Liberty Township North Liberty Lincoln Township Walkerton Olive Township LaPorte County Kankakee Township Pleasant Township Lincoln Township Washington Township Kingsbury Johnson Township Union Township Kingsford Heights Noble Township Hanna Township Hanna Clinton Township Prairie Township Cass Township Wanatah Dewey Township LaCrosse Starke County Davis Township Hamlet Jackson Township Railroad Township. The Yellow River joins the Kankakee River here. English Lake Lomax Porter County Washington Township Morgan Township Pleasant Township Kouts Union Township Boone Township Hebron Jasper County While all of Jasper County is in the Kankakee River basin, most of the county is on the Iroquois River, rather than directly on the Kankakee's main stem. Kankakee Township Wheatfield Township Dunns Bridge Wheatfield Keener Township Baums Bridge Demote Lake County Winfield Township Winfield Eagle Creek Township Center Township Cedar Creek Township St. John Township St. John Hanover Township Cedar Lake West Creek Township Schneider Shelby Newton County Like Jasper County, Newton County is in the Kankakee River basin, but most of the county is on the Iroquois River, and not on the Kankakee's main stem. Lincoln Township Roselawn Thayer Colfax Township Lake Township Sumava Resort