Which North American Great Lake is the shallowest by average depth?

Lake Erie is the shallowest of North America’s five Great Lakes by average depth.

Its average depth is about 19 metres (62 feet), far less than Lake Huron’s roughly 59 metres, Lake Michigan’s 85 metres, Lake Ontario’s 86 metres and Lake Superior’s 147 metres. Erie’s maximum depth is only about 64 metres (210 feet), making it shallow even at its deepest point.

The lake’s basin was shaped by glaciers, but the ice had less erosive power this far south than in the basins of the deeper Great Lakes. Erie’s western basin is especially shallow, averaging only around 7.6 metres (25 feet). That shallow water warms quickly in summer and is also more likely to freeze in winter.

Its depth helps explain several environmental and practical features. Lake Erie can develop rapidly moving waves, or seiches, during strong winds, and warm conditions have raised concerns for power plants that use lake water for cooling. The lake is shared by Canada and the United States and drains through the Niagara River.