Great Lakes fast facts

If you seek a pleasant peninsula, look about you. The Michigan state motto is a great reminder of two things Michiganders hold dear: the Great Lakes that literally shape our state and the beauty found within those peninsulas. The Great Lakes — Huron, Ontario, Michigan, Erie, and Superior — make up the largest freshwater system on the planet.

The Great Lakes are connected through a system of canals and connecting waterways, such as the Detroit River and Lake St. Clair. These enable water to flow from Lake Superior all the way to the St. Lawrence Seaway and the Atlantic Ocean.

Size, length, and volume

  • Total length of Great Lakes shoreline, including islands: 11,000 miles
  • World’s supply of surface freshwater in the Great Lakes: 20 percent
  • Combined surface area of all the Great Lakes: 94,000 square miles (244,000 square kilometers).
  • The surface area of the Great Lakes is larger than: Connecticut, Massachusetts, New Hampshire, New Jersey, New York, Rhode Island, and Vermont combined
  • Gallons of fresh water: 6 quadrillion (22.7 quadrillion liters), enough to submerge the entire continental United States in nearly 10 feet of water

Key facts

  • Approximately 34 million people in the United States and Canada live in the Great Lakes basin — 8 percent of the U.S. population and about 32 percent of Canada’s population.
  • More than 3,500 species of plants and animals live in the Great Lakes basin, including 170+ species of fish.
  • The Great Lakes are among the world’s 15 largest lakes.
  • A geologically “young” system compared to the world’s oceans, the Great Lakes were shaped by glaciers about 10,000 years ago.

Managing the Great Lakes

Making decisions about the Great Lakes is no easy task. This massive system touches eight states (Minnesota, Wisconsin, Illinois, Indiana, Michigan, Ohio, Pennsylvania, and New York), two Canadian provinces (Ontario and Quebec, if you include the St. Lawrence Seaway), and many tribal, county, and city jurisdictions. Many groups of people have a stake in Great Lakes management strategies: anglers, teachers, homeowners, commercial fishermen, policy officials, scientists, tourists, business owners, farmers, and more. It’s important for every group to have a voice in making major decisions about the future of the Great Lakes.

U.S. and Canadian federal governments have a long history of working together on behalf of these shared resources. One outcome of this partnership has been the Great Lakes Water Quality Agreement, signed by both nations in 1972 to coordinate management goals and actions. The Great Lakes states also signed a formal agreement called the Great Lakes Compact in 2008, agreeing to regulate diversions of water outside the Great Lakes basin. These are just two of the many shared management strategies developed by federal, state, county, tribal, and local governments.

Michigan’s watersheds

A watershed is an area of land where all the rain and melting snow drains to a single body of water. Watersheds come at all scales, from a puddle to a river to a Great Lake. Also called drainage or catchment basins, watershed boundaries are determined by high points in the landscape.

In Michigan, virtually all watersheds eventually drain into one of the Great Lakes. What we do on the land can profoundly affect our water systems. A river or lake is only as healthy as the water draining into it, and water is only as clean as the land it flows over. Healthy watersheds reduce flood risk, support crops, filter pollutants, mitigate the effects of climate change, and boost human wellbeing. What watershed do you live in? Use this map to find out: