Overview
Lake Superior is the largest freshwater lake in the world by surface area - about 31,700 square miles - bordering Minnesota, Wisconsin, Michigan, and Ontario. It is the headwater Great Lake, discharging through the St. Marys River to Lakes Huron-Michigan. Superior holds roughly half of the Great Lakes' water by volume despite sharing the system with four other lakes. Seasonal weather and local access conditions reward a quick check of recent reports.
Average depth is about 483 feet and maximum depth about 1,332 feet, with more than 2,700 miles of shoreline including islands. Cold, clear water and rocky coasts define the Minnesota North Shore and Apostle Islands character. Minnesota's North Shore drops quickly into deep water, while the Apostle Islands and south shore offer different seascapes.
Lake trout, salmon, and other coldwater fisheries are managed by state, provincial, and tribal agencies. State parks, harbors, and the Twin Ports of Duluth-Superior provide major public and commercial access. Duluth-Superior harbor, Two Harbors, and Grand Marais are primary Minnesota access and refuge points.
Levels are expressed on IGLD 1985 with a published Low Water Datum / chart datum near 601.1 feet. There is no reservoir-style full/winter pool; monitoring lake-wide water levels remains important for harbors, seiches, and shoreline flooding. Cold temperatures, fog, and seiches demand marine-worthy preparation even on apparently calm summer days. Visitors who track the official gage before launching avoid the most common access surprises.
Current Conditions
Lake Superior is currently 1.05 feet above its long-term average and has fallen slightly over the past week.
- 7-day trendFallingLatest movement can differ from the seven-day trend.
- 7-day changeUp 0.08 ft
- 30-day changeUp 0.04 ft
- Drought conditionsAbnormally Dry
About This Lake
Learn how this lake is managed, what affects its water level, and where Lake Insights gets its data.
Lake Superior is a 20,303,850-acre Great Lake. Its levels reflect basin water balance and connecting-channel flows.