The names of the five Great Lakes are Lake Superior, Lake Michigan, Lake Huron, Lake Erie and Lake Ontario. The Great Lakes are the largest surface freshwater systems on Earth and contain roughly 21 percent of the world water supply.
The Great Lakes are on the border of the United States and Canada. These lakes contain approximately 84 percent of North America's surface water and are the home to more than 3,500 species of plants and animals. Lake Superior is the largest of the five lakes by volume, and it is also the deepest and the coldest. The smallest and shallowest lake is Lake Erie. Lake Michigan is the only Great Lake that is entirely in the United States, and it is also the second largest Great Lake by volume. Together, these lakes span more than 750 miles and provide water for a variety of uses, including consumption, power and transportation, according to the Environmental Protection Agency.
The Great Lakes are very popular for boating, fishing and other water activities. The lakes are also very sensitive to pollutants. According to the Environmental Protection Agency, the pollutants that enter any of the Great Lakes are generally retained and become more concentrated over time. Common sources of pollution include waste from cities, industrial discharge, farm chemicals and pollution that enters directly from the atmosphere.