B
Lake Superior Pt 9
Cook County, Minnesota
Water Quality Grade: B — Good
Moderate clarity — visible to about 7.9 feet. Phosphorus level: 7.5 µg/L. Chlorophyll-a: 1.3 µg/L.
| Metric | Value | Grade |
|---|---|---|
| Water Clarity (Secchi Depth) | 2.4 m | C |
| Phosphorus | 7.5 µg/L | A |
| Chlorophyll-a (Algae) | 1.3 µg/L | A |
County Ranking
Ranked #45 of 144 lakes in Cook County
Data Sources
Data from the EPA Water Quality Portal
Grading methodology based on Metropolitan Council standards
Most recent sample: 2025-09-16
Monitoring stations: 1