The lake has two primary tributaries, the Wolf and Fox Rivers, which combine at Lake Butte des Morts. The Fox River flows east through Oshkosh and into Lake Winnebago at its west central shore, then flows out at the northwest shore, around Doty Island at Neenah-Menasha to Little Lake Butte des Morts. The river then flows northeast and empties into Green Bay and serves as part of the Fox-Wisconsin Waterway. Lake Winnebago is part of a larger system of lakes in Wisconsin known as the Winnebago Pool.