Great Lakes profile

The diagram shows the profile of the Great Lakes as follows:

• Lake Michigan's surface is 176 metres above sea level; its greatest depth is 281 metres below surface level.
• Lake Superior's surface is 183 metres above sea level; its greatest depth is 405 metres below surface level.
• Lake Huron's surface is 176 metres above sea level; its greatest depth is 229 metres below surface level.
• Lake Erie's surface is 173 metres above sea level; its greatest depth is 64 metres below surface level.
• Lake Ontario's surface is 74 metres above sea level; its greatest depth is 244 metres below surface level.

Also shown are the approximate positions of Duluth, Chicago, St. Marys River (Soo Locks), the Straits of Mackinac, St. Clair River, Lake St. Clair, the Detroit River, Welland Canal and the St. Lawrence River.

Note: 1. The profile is taken along the long axes of the lakes.
2. The vertical exaggeration is 2000 times.

Source: The Great Lakes – An Environmental Atlas and Resource Book, 1987.