Michigan, Lake

Lake in north-central USA, the third largest of the Great Lakes and the only one lying entirely within the USA, it is bordered by Michigan to the north and east, Indiana to the south, and Wisconsin and Illinois to the west; area 58,000 sq km/22,390 sq mi. The lake is 517 km/321 mi long, 190 km/118 mi at its widest point, has a maximum depth of 282 m/925 ft, and lies 176 m/577 ft above sea level. Lake Michigan is joined to Lake Huron by the Straits of Mackinac in the north. Green Bay is its largest inlet, and Chicago and Milwaukee are its main ports. The first European to see the Lake Michigan was the French explorer Jean Nicolet, in 1634.

Pollution from the great industrial complex of Chicago has put the ecological balance of the lake in danger; with currents on the lake being slight, the pollutant levels have tended to build up. The Lake Michigan Federation (1971) was set up to protect and restore the lake.