A
Long Lost Lake
Clearwater County, Minnesota
Water Quality Grade: A — Excellent
Crystal clear — you can see 23.0 feet down. Phosphorus level: 10.5 µg/L.
| Metric | Value | Grade |
|---|---|---|
| Water Clarity (Secchi Depth) | 7.01 m | A |
| Phosphorus | 10.5 µg/L | A |
| Chlorophyll-a (Algae) | No data |
County Ranking
Ranked #8 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: 2025-09-02
Monitoring stations: 4