Erie, Lake

Erie, Lake, southernmost and fourth-largest of the Great Lakes of North America, bordered on the north by Ontario, on the east by New York, on the south by Pennsylvania and Ohio, and on the west by Michigan. The boundary between the United States and Canada generally follows the long axis of the lake, which extends in a north-eastern and south-western direction for 388 km (241 mi). Lake Erie covers 25,667 sq km (9,910 sq mi), almost evenly divided between the United States and Canada; its drainage basin includes about 58,790 sq km (22,700 sq mi). The mean elevation of the lake is 174 m (570 ft), and its maximum breadth is 92 km (57 mi). The lake's greatest depth is 64 m (210 ft), but its average depth is only 19 m (62 ft), making it the shallowest of the five Great Lakes.

Lake Erie receives the waters of Lake Huron, which lies to the north, via the St Clair River, Lake St Clair, and the Detroit River, all of which are navigable. Many smaller rivers also flow into Lake Erie. These include Big Creek and the Grand River, from the north; Cattaraugus Creek, from the east; the Grand, Cuyahoga, Sandusky, Portage, and Maumee rivers, from the south; and the Raisin and Huron rivers, from the west. The only outlets of Lake Erie are the Niagara River and the Welland Ship Canal both of which connect with Lake Ontario. Several small islands are located in the western part of Lake Erie. Among them are Pelee Island, in Ontario (Canada's southern-most point), and Kelleys, North Bass, Middle Bass, and South Bass islands, in Ohio.

Because of its relative shallowness, Lake Erie presents various hazards to navigation in stormy weather, when dangerous ground swells are common. In addition, the lake is closed by ice to shipping from mid-December to late March. Despite these obstacles, great quantities of cargo are carried on Lake Erie, which is an important component of the St Lawrence Seaway and is also connected with the Hudson River (and then with the Atlantic Ocean at New York) by the Erie Canal. Vast amounts of iron ore are shipped from the Lake Superior region to ports along the southern shore of Lake Erie. These ports, which serve the great steel industry of Ohio and Pennsylvania, include Erie, Pennsylvania, and Conneaut, Ashtabula, and Cleveland, Ohio. Buffalo, New York, on the eastern shore, is a major grain port, and Toledo, Ohio, in the west, handles much coal.

The French explorer Louis Jolliet was the first European to discover Lake Erie, in 1669, after which fur-trading posts were established on its shores by France. Great Britain won control of the lake in the mid-18th century, during the French and Indian War and retained all of it until Jay's Treaty of 1794 divided sovereignty over the area between Britain and the United States. Lake Erie was the scene of an American naval victory during the War of 1812. In the 20th century much untreated industrial and municipal waste was discharged into Lake Erie from the industrialized Ohio shore, thereby severely polluting it.