How deep are the Great Lakes?
Lake Superior is the deepest Great Lake at 1,332 feet, followed by Lake Michigan (925 ft), Lake Ontario (802 ft), Lake Huron (750 ft), and Lake Erie (210 ft). Figures are from the US EPA and NOAA GLERL physical features tables, measured at Low Water Datum. Four of the five have free interactive depth maps, linked in the table below.
Great Lakes depths compared
| Lake | Maximum depth | Average depth | Depth map |
|---|---|---|---|
| Lake Superior | 1,332 ft | 483 ft | How deep is Lake Superior? |
| Lake Michigan | 925 ft | 279 ft | Lake Michigan depth map |
| Lake Ontario | 802 ft | 283 ft | Lake Ontario depth map |
| Lake Huron | 750 ft | 195 ft | Lake Huron depth map |
| Lake Erie | 210 ft | 62 ft | Lake Erie depth map |
| Lake St. Clair | ~21 ft natural (shipping channel deeper) | ~11 ft | Contour map |
Sources: US EPA, Physical Features of the Great Lakes; NOAA GLERL. Depths at Low Water Datum. Lake St. Clair is not a Great Lake and appears in neither table; its figures are approximate.
Why the depth differences matter for fishing
Depth drives everything about how these lakes fish. Erie's shallow, warm basin makes it the most biologically productive Great Lake and the world's best walleye water. Superior's cold basins, plunging past 1,300 feet, hold lake trout that live for decades and grow slowly. Michigan and Huron sit between, with two-story fisheries: warm-water species inshore, salmon and trout suspended over the deep basins. Ontario is the smallest Great Lake by surface area but the second deepest on average, which is why its king salmon fishery holds up in high summer when the fish follow the thermocline down.
Great Lakes depth FAQs
- What is the deepest Great Lake?
- Lake Superior, at 1,332 feet maximum and 483 feet average depth. It holds more water than the other four Great Lakes combined.
- What is the shallowest Great Lake?
- Lake Erie, at 210 feet maximum and just 62 feet average. Its shallowness is why it warms fastest, produces the most walleye, and kicks up dangerous seas quickly in wind.
- How deep are the Great Lakes in order?
- From deepest to shallowest by maximum depth: Lake Superior 1,332 ft, Lake Michigan 925 ft, Lake Ontario 802 ft, Lake Huron 750 ft, Lake Erie 210 ft. By average depth the order changes slightly: Superior 483 ft, Ontario 283 ft, Michigan 279 ft, Huron 195 ft, Erie 62 ft.
- Is Lake Ontario deeper than Lake Huron?
- Yes, on both measures. Lake Ontario reaches 802 feet maximum against Lake Huron's 750, and Ontario's 283 foot average is much deeper than Huron's 195, despite Ontario being the smallest Great Lake by surface area.
Inland instead? Browse all 442 lake depth maps · US fishing license guide