Overview
Lake St. Clair is a roughly 275,200-acre (about 430 square mile) lake on the Michigan–Ontario border between Lake Huron and Lake Erie, receiving the St. Clair River and discharging through the Detroit River. It is part of the Great Lakes connecting-channel system; the U.S. Army Corps of Engineers and Canadian partners publish coordinated water-level information for the lake and its connecting rivers.
With about 130 miles of shoreline, an average depth near 11 feet, and a maximum depth of only about 21 feet, St. Clair is broad, shallow, and highly responsive to wind. Shipping channels are dredged through the lake; natural basins, wetlands, and the St. Clair River delta fringe much of the Michigan and Ontario shores, creating rich fish and waterfowl habitat beside a major metropolitan corridor.
The lake is a premier walleye, muskie, bass, and panfish fishery and a major boating water for Metro Detroit and Windsor. Michigan anglers should consult the Michigan Department of Natural Resources for regulations and access, while Canadian waters are managed under Ontario fisheries rules across the international boundary.
Lake St. Clair does not use reservoir-style full, winter, or flood pools. Chart datum (Low Water Datum) is 572.3 feet IGLD85, and lake-wide elevations are reported in the International Great Lakes Datum of 1985 (IGLD85). Wind setup can change local levels quickly on this shallow basin, so monitoring current IGLD85 levels and marine forecasts is important for safe boating and shoreline use.
Current Conditions
- 7-day trendFallingLatest movement can differ from the seven-day trend.
- 7-day changeDown 0.10 ft
- 30-day changeDown 0.33 ft
- Drought conditionsNo Drought
About This Lake
Learn how this lake is managed, what affects its water level, and where Lake Insights gets its data.
Lake St. Clair is a 275,200-acre natural lake with management context from U.S. Army Corps of Engineers / Environment and Climate Change Canada. Levels respond to rainfall, runoff, and natural inflows and outflows.