How Clean Is Island Lake?
Island Lake has very poor water quality and a high algae bloom risk. It received a water quality grade of F (Very Poor) based on EPA monitoring data. Water clarity (Secchi depth): 4.5 ft. Phosphorus: 30 µg/L. Chlorophyll-a (algae): 34.3 µg/L. Trophic State Index: 58.
Cleanliness Snapshot
| Metric | Island Lake | Minnesota avg |
|---|---|---|
| Overall Grade | F | C |
| Water Clarity (Secchi) | 4.5 ft | — |
| Phosphorus | 30 µg/L | <30 = clean |
| Chlorophyll-a (Algae) | 34.3 µg/L | <10 = clean |
| Trophic State Index | 58 | <50 = clean |
How does Island Lake compare?
Island Lake's grade of F falls below the Minnesota state average of C. It ranks #12 of 12 lakes in Mahnomen County by water quality score. Multi-year monitoring data shows water quality is improving based on 2 years of records.