Winnebago River

The Winnebago River rises in Winnebago County, Iowa, north of Leland and flows south through Forest City, then east and southeast through Mason City on its way to the Shell Rock River at Rockford.

Headwater tributaries of the Winnebago River extend north into southern Minnesota.

The Winnebago River measures approximately 330 cubic feet per second at Mason City.

[4] This was the highest flood water stage in recorded history for the Winnebago River.

The flooding was part in due to severe rainfall in the river's basin between May 29 and June 12 of that year.