Great Lakes Information

Great Lakes Information


6 quadrillion gallons of fresh water; one-fifth of the world’s fresh surface water (only the polar ice caps and Lake Baikal in Siberia contain more); 95 percent of the U.S. supply; 84 percent of the surface water supply in North America. Spread evenly across the continental U.S., the Great Lakes would submerge the country under about 9.5 feet of water.


More than 94,000 square miles/244,000 square kilometres of water (larger than the states of New York, New Jersey, Connecticut, Rhode Island, Massachusetts, Vermont, and New Hampshire combined, or about 23 percent of the province of Ontario). About 295,000 square miles/767,000 square kilometres in the watershed (the area where all the rivers and streams drain into the lakes).


United States and Canada — 10,900 mi/17,549 km (including connecting channels, mainland and islands). The Great Lakes shoreline is equal to almost 44 percent of the circumference of the earth, and Michigan’s Great Lakes coast totals 3,288 mi/5,294 km, more coastline than any state but Alaska.

References: Great Lakes Basin brochure, 1990, Michigan Sea Grant

Lake Erie

Lake Erie is the eleventh largest lake in the world (by surface area), and the fourth largest of the Great Lakes in surface area and the smallest by volume.
Ninety-five percent of Lake Erie’s total inflow of water comes via the Detroit River water from all the “upper lakes” — Superior, Michigan and Huron — the St. Clair River, Lake St. Clair and numerous tributaries. The rest comes from precipitation. Lake Erie is the shallowest of the Great Lakes and is especially vulnerable to fluctuating water levels.

Wind setups (wind pushing the water from one end of the lake toward the other), usually from west to east, have produced large short- term differences in water levels at the eastern and western ends of the lake, the record being more than 16 ft (4.88 m).

The water provided by Lake Erie for waterborne commerce, navigation, manufacturing, and power production has led to intensive industrial development along its shore, but the basin’s moderate temperatures have also encouraged recreation and agriculture.

Lake Erie is the warmest and most biologically productive of the Great Lakes, and the Lake Erie walleye fishery is widely considered the best in the world.
Point Pelee National Park in Lake Erie is the southernmost point on Canada’s mainland.


LENGTH: 241 miles / 388 km
BREADTH: 57 miles / 92 km
AVERAGE DEPTH: 62 ft. / 19 m.
MAXIMUM DEPTH: 210 ft. / 64 m.


VOLUME: 116 cubic miles / 484 cubic km.
WATER SURFACE AREA: 9,910 sq. miles / 25,700 sq. km.
TOTAL DRAINAGE BASIN AREA: 30,140 sq. miles / 78,000 sq. km.


Indiana: 1300 sq mi; 3300 sq km
Michigan: 5800 sq mi; 15,100 sq km
New York: 1600 sq mi; 4200 sq km
Ohio: 11,700 sq mi; 30,400 sq km
Ontario: 8800 sq mi; 22,800 sq km
Pennsylvania: 500 sq mi; 1400 sq km


SHORELINE LENGTH (including islands): 871 miles / 1,402 km.
ELEVATION: 569 ft. / 173 m.
OUTLET: Niagara River and Welland Canal
RETENTION/REPLACEMENT TIME: 2.6 years (shortest of the Great Lakes)


NAME: The greater part of its southern shore was at one time occupied by a nation known to the Iroquois League as the “Erielhonan,” or the “long-tails,” a tribe of Indians from which the lake derived its name. This name is always mentioned by the early French writers as meaning “cat”; Lac du Chat means “Lake of the Cat.” Many attribute this reference to the wild cat or panther.

Lake Huron

Lake Huron is the second largest Great Lake by surface area and the fifth largest freshwater lake in the world.

It has the longest shoreline of the Great Lakes, counting the shorelines of its 30,000 islands.

Manitoulin Island is the largest freshwater island in the world.

Georgian Bay and Saginaw Bay are the two largest bays on the Great Lakes.

Early explorers listed Georgian Bay as a separate sixth lake because it is nearly separated from the rest of Lake Huron by Manitoulin Island and the Bruce Peninsula.

Georgian Bay is large enough to be among the world’s 20 largest lakes.

Huron receives the flow from both Lake Superior and Lake Michigan, but water flows through Lake Huron (retention time) much more quickly than through either of them.

Huron was the first of the Great Lakes to be discovered by European explorers.

Shipwrecks are scattered throughout the lake, with five bottomland preserves in Michigan and a national park in Ontario designated to protect the most historically significant ones.

The Lake Huron basin is heavily forested, sparsely populated, scenically beautiful, and economically dependent on its rich natural resources.


LENGTH: 206 miles / 332 km.
BREADTH: 183 miles / 245 km.
AVERAGE DEPTH: 195 ft. / 59 m.
MAXIMUM DEPTH: 750 ft. / 229 m.
VOLUME: 850 cubic miles / 3,540 cubic km.
WATER SURFACE AREA: 23,000 sq. miles / 59,600 sq. km.
TOTAL DRAINAGE BASIN AREA: 51,700 sq. miles / 134,100 sq. km.


Michigan: 16,100 sq mi; 41,700 sq km
Ontario: 35,200 sq mi; 91,100 sq km


SHORELINE LENGTH (including islands): 3,827 miles / 6,157 km.
ELEVATION: 577 ft. / 176 m.
OUTLET: St. Clair River to Lake Erie
NAME: Since its French discoverers knew nothing as yet of the other lakes, they called it La Mer Douce, the sweet or fresh-water sea. A Sanson map in 1656 refers to the lake as Karegnondi, simply meaning “lake” in the Petan Indian language.

Lake Michigan

Lake Michigan is the third largest Great Lake by surface area and the sixth largest freshwater lake in the world.

Because Lake Michigan is joined to Lake Huron at the Straits of Mackinac, they are considered one lake hydrologically.

Many rivers and streams flow into Lake Michigan, and the major tributaries are the Fox-Wolf, the Grand and the Kalamazoo.

There is a diversion from the lake into the Mississippi River basin through the Illinois Waterway at the Chicago River.

Lake Michigan’s cul-de-sac formation means that water entering the lake circulates slowly and remains for a long time (retention) before it leaves the basin through the Straits of Mackinac.

Small lunar tidal effects have been documented for Lake Michigan1.

Internal waves (upwellings) can produce a 15 degree C. water temperature decrease along the coast in only a few hours, requiring drastic alterations in fishing strategy1.

The northern part of the Lake Michigan watershed is covered with forests, sparsely populated, and economically dependent on natural resources and tourism, while the southern portion is heavily populated with intensive industrial development and rich agricultural areas along the shore.

The world’s largest freshwater dunes line the lakeshore.

Millions of people annually visit the dunes/beaches at state and national parks and lakeshores.


LENGTH: 307 miles / 494 km.
BREADTH: 118 miles / 190 km.
AVERAGE DEPTH: 279 ft. / 85 m
MAXIMUM DEPTH: 925 ft. / 282 m.
VOLUME: 1,180 cubic miles / 4,920 cubic km.
WATER SURFACE AREA: 22,300 sq. miles / 57,800 sq. km.
TOTAL DRAINAGE BASIN AREA: 45,600 sq. miles / 118,000 sq. km.


Illinois: 100 sq mi; 300 sq km
Indiana: 2200 sq mi; 5800 sq km
Michigan: 28,300 sq mi; 73,300 sq km
Wisconsin: 14,200 sq mi; 36700 sq km


SHORELINE LENGTH (including islands): 1,638 miles / 2,633 km.
ELEVATION: 577 ft. / 176 m.
OUTLET: Straits of Mackinac to Lake Huron
NAME: Champlain called it the Grand Lac. It was later named “Lake of the Stinking Water” or “Lake of the Puants,” after the people who occupied its shores. In 1679, the lake became known as Lac des Illinois because it gave access to the country of the Indians, so named. Three years before, Allouez called it Lac St. Joseph, by which name it was often designated by early writers. Others called it Lac Dauphin. Through the further explorations of Jolliet and Marquette, the “Lake of the Stinking Water” received its final name of Michigan.

Another story recounts that Nicolet, the first European to set foot in Wisconsin in 1634, landed on the shores of Green Bay and was greeted by Winnebago Indians, whom the French called “Puans.” Lake Michigan was labeled as “Lake of Puans” on an early and incomplete 1670 map of the region that showed only the northern shores of the lake. However, only Green Bay is labeled as “Baye de Puans” (Bay of the Winnebago Indians) on maps from 1688 and 1708. On the 1688 map, Lake Michigan is called Lac des Illinois.

An Indian name for Lake Michigan was “Michi gami.”

Lake Ontario

Lake Ontario, the 14th largest lake in the world, is the smallest of the Great Lakes in surface area.
It ranks fourth among the Great Lakes in maximum depth, but its average depth is second only to Lake Superior.

Lake Ontario lies 325 ft (99 m) below Lake Erie, at the base of Niagara Falls.

The falls were always an obstacle to navigation into the upper lakes until the Trent-Severn Waterway, along with the Welland and Erie Canals were built to allow ships to pass around this bottleneck. The oldest lighthouse on the U.S. side of the Great Lakes was set up at Fort Niagara in 1818 to aid navigation.

The basin is largely rural, with many scenic resort areas.

A few large urban areas, including Ontario’s capital city (Toronto), are located on the Canadian shoreline.

In 1972-73, 1,000 scientists, engineers and technicians undertook the most extensive survey ever made of a Great Lake.


LENGTH: 193 miles / 311 km.
BREADTH: 53 miles / 85 km.
AVERAGE DEPTH: 283 ft. / 86 m
MAXIMUM DEPTH: 802 ft. / 244 m.
VOLUME: 393 cubic miles / 1,640 cubic km.
WATER SURFACE AREA: 7,340 sq. miles / 18,960 sq. km.
TOTAL DRAINAGE BASIN AREA: 24,720 sq. miles / 64,030 sq. km.


New York: 13,500 sq mi; 35,000 sq km
Ontario: 11,200 sq mi; 29,100 sq km
Pennsylvania: 100 sq mi; 300 sq km


SHORELINE LENGTH (including islands): 712 miles / 1,146 km.
ELEVATION: 243 ft. / 74 m.
OUTLET: St. Lawrence River to the Atlantic Ocean
NAME: Champlain first called it Lake St. Louis in 1632. On a Sanson map in 1656, it remained Lac de St. Louis. In 1660, Creuxius gave it the name Lacus Ontarius. Ontara in Iroquois means “lake,” and Ontario, “beautiful lake.”

Lake Superior

Lake Superior is the largest of the Great Lakes in surface area and volume. Lake Superior could contain all the other Great Lakes plus three more lakes the size of Lake Erie. Water flows into the lake from many small rivers and streams. The Long Lac and Ogoki diversions in Canada channel water into Lake Superior that would otherwise flow into Hudson Bay. By order of the International Joint Commission, the lake’s level, controlled by gates on the St. Marys River at Sault Ste. Marie, may not exceed 602 ft (183 m) above sea level. Each year a small percentage of the lake’s water flows out through the St. Marys River, and it takes almost two centuries for the water to be completely replaced (retention time). The Lake Superior drainage basin is rich in natural resources and scenic beauty. It is sparsely populated and economically dependent on its natural resources, which include metals, minerals, forests and recreation/tourism opportunities such as national lakeshores and national/state/provincial parks. It is particularly known for its clear, cold water and agate beaches. A circle tour guides highway travelers around the lakeshore. Many shipwrecks in Lake Superior are now protected in bottomland preserves and accessible to recreational divers. In 1985, scientists using a submersible vessel descended for the first time to the deepest part (-1,333 ft./-405 m) of Lake Superior near the Pictured Rocks National Lakeshore in Michigan waters.


LENGTH: 350 miles / 563 km.
BREADTH: 160 miles / 257 km.
AVERAGE DEPTH: 483 ft. / 147 m.
MAXIMUM DEPTH: 1,332 ft. / 406 m.
VOLUME: 2,900 cubic miles / 12,100 cubic km.
WATER SURFACE AREA: 31,700 sq. miles / 82,100 sq. km.


TOTAL DRAINAGE BASIN AREA: 49,300 sq. miles / 127,700 sq. km.


Michigan: 7500 sq mi; 19,300 sq km
Minnesota: 6200 sq mi; 16,000 sq km
Ontario: 32,200 sq mi; 83,300 sq km
Wisconsin: 3000 sq mi; 7700 sq km


SHORELINE LENGTH (including islands): 2,726 miles / 4,385 km.
ELEVATION: 600 ft. / 183 m.
OUTLET: St. Marys River to Lake Huron
NAME: The first French explorers approaching the great inland sea by way of the Ottawa River and Lake Huron referred to their discovery as le lac superieur. Properly translated, the expression means “Upper Lake,” that is, the lake above Lake Huron. Kitchi-gummi, a Chippewa Indian translation, signifies Great-water or Great-lake. A Jesuit name, Lac Tracy, was never officially adopted.


References: Great Lakes Atlas, Environment Canada and U.S. Environmental Protection Agency, 1995

Additional Great Lakes Information