Big Lake is an open body of water surrounded by marshy islands in Navigation Pool 9 of the Upper Mississippi River. It lies where the Iowa, Minnesota and Wisconsin borders come together, just north of Lansing, Iowa. It is part of the Upper Mississippi River National Wildlife and Fish Refuge.

Big Lake
Big Lake Show map of Iowa Big Lake Show map of the United States
(United States Environmental Protection Agency)
Location	Allamakee County, Iowa
Coordinates	43.3992°N 91.2177°W / 43.3992; -91.2177
Type	Reservoir
Primary inflows	Upper Mississippi River
Primary outflows	Upper Mississippi River
Basin countries	United States

The Army Corps of Engineers maintains the lake's integrity as fish habitat.

Sources

• Army Corps of Engineers (retrieved 2 April 2007)