The Lake Superior Basin is located in northwest Wisconsin, and includes parts of Douglas, Bayfield, Ashland, and Iron counties — an area with landscapes, shorelands and waterways unique to Wisconsin.

Special water features of the Basin include:

The Wisconsin Department of Natural Resources provides this watershed information site about fisheries, forests, wildlife, pollution prevention, watershed protection, tributaries, environmental protection and regulation, invasive aquatic species, recreation, and special programs.  You can

Surface Water DataViewer  View and analyze watershed-related data (lakes and streams, monitoring stations, impaired waters, and Outstanding/Exceptional Resource Waters) in Wisconsin.

Ecological Landscapes  

The Lake Superior Basin landscapes range from estuaries to globally significant pine barrens and includes the Superior Coastal Plain, Northwest Lowlands, Northwest Sands landscapes defined by the Wisconsin Department of Natural Resources.

Ecoregional Subsections

Lake Superior Basin Regional Assessment Report Summary  The Lake Superior Basin is shaped by the interplay between its unique soils, hydrology and forestry cover.  The glacial past and ancient lake beds of clay and sand make this area of special concern for water quality for Lake Superior’s streams in Wisconsin.  A regional assessment of the Basin was made by Carmen Hardin using the National Hierarchical Framework of Ecological Units.  The 2010 Lake Superior Basin Regional Assessment Report is found here.  The Assessment describes the ecological, social and economic attributes of Wisconsin’s Lake Superior Basin. This information can help land managers make decisions with watershed health in mind.


Lake Superior Regional Assessment and Report Compendium  A compendium of scientific assessments and studies on natural resource issues related to watershed health in Wisconsin’s Lake Superior Basin was developed in 2010 by Kristen Tomaszewski of the Wisconsin Department of Natural Resources.  The purpose of the compendium is to provide a single source for all scientific reports on the Lake Superior Basin in Wisconsin.  The compendium has been developed as a starting point and is intended to be expanded upon as more studies and assessments become available.  The research compendium is found here.

Rivers (from west to east)

St. Louis River  The St. Louis River, with a watershed of 3,634 square miles, is the largest U.S. tributary to Lake Superior. It begins near Hoyt Lakes, Minnesota, and flows southwesterly for 179 miles before taking on the characteristics of a 12,000-acre freshwater estuary near Lake Superior. Below Jay Cooke State Park, the river turns to the northeast, and flows between the Twin Ports cities of Duluth, Minnesota, and Superior, Wisconsin.   Located at the westernmost edge of the Great Lakes—St. Lawrence Seaway System, the Twin Ports are the farthest inland seaport in the world, 2,342 miles from the Atlantic Ocean.   The St. Louis River has been listed as an Area of Concern due to past land use, habitat loss and pollution.  The St. Louis River estuary is also the site of the Lake Superior National Estuarine Research Reserve.

City of Superior streams: Bear Creek, Bluff Creek, Newton Creek, Nemadji River, Dutchman’s Creek

Amnicon River  Flows from over bedrock waterfalls at Amnicon State Park then drops into highly erodible red clays.

Middle River  Upper watershed wetlands are important sources of water.

Iron River  Headwaters are in the sand barrens, lower reaches contain wetlands.  Mostly in private ownership.

Brule River  A spring-fed, historical river famous for trout fishing and canoeing.

South Shore Streams  Dozens of streams that flow directly into Lake Superior and include several State Natural Areas and National Lake Shore.  These include: Middle River, Flag River, Cranberry River, Saxine Creek, Sand River, Raspberry River, Onion River, Sioux River, Thompson’s Creek.

Head of Chequamegon Bay receives water from Whittlesley Creek, Fish Creek, Bay City Creek.  Includes the Whittlesley Creek National Wildlife Refuge and the Northern Great Lakes Visitor Center.

The Bad River collects water from the White, Potato, Tyler’s Forks and Marengo Rivers.  The lower Bad River to Kakagon Sloughs flows through tribal lands.

Montreal River  Forms the boundary between Wisconsin and Michigan.  The Ojibwe name for the river is Gaa-waasijiwaang, meaning “where there is whitewater“.    The Montreal River has four named waterfalls.


The Lake Superior Basin has numerous inland wetlands and along Lake Superior.  Many of these wetlands are includes in 100 Wisconsin Wetland Gems identified by the Wisconsin Wetlands Association.

Significant wetlands include: Bark Bay & Lost Creek Bog, Bibon Swamp, Big Bay, Kakagon-Bad River Sloughs, Nemadji Floodplain Forest, Outer Islands Sandspit and Lagoon, Pokegema-Carnegie Wetlands,  Red Cliff Raspberry Bay, Sand Bay, St. Louis River Marshes, Stockton Island Tombolo and Sultz Swamp.