A
Rock Lake
Clearwater County, Minnesota
Water Quality Grade: A — Excellent
Good clarity — visible to about 11.2 feet. Phosphorus level: 16.5 µg/L.
| Metric | Value | Grade |
|---|---|---|
| Water Clarity (Secchi Depth) | 3.4 m | B |
| Phosphorus | 16.5 µg/L | A |
| Chlorophyll-a (Algae) | No data |
County Ranking
Ranked #13 of 42 lakes in Clearwater County
Data Sources
Data from the EPA Water Quality Portal
Grading methodology based on Metropolitan Council standards
Most recent sample: 2025-09-04
Monitoring stations: 2