How Clean Is Island Lake?
Island Lake has fair water quality — typical of lakes with moderate nutrient enrichment. It received a water quality grade of C (Fair) based on EPA monitoring data. Water clarity (Secchi depth): 6.4 ft. Phosphorus: 30 µg/L. Trophic State Index: 52.
Cleanliness Snapshot
| Metric | Island Lake | Minnesota avg |
|---|---|---|
| Overall Grade | C | C |
| Water Clarity (Secchi) | 6.4 ft | — |
| Phosphorus | 30 µg/L | <30 = clean |
| Trophic State Index | 52 | <50 = clean |
How does Island Lake compare?
Island Lake's grade of C matches or beats the Minnesota state average of C. It ranks #13 of 16 lakes in Mahnomen County by water quality score.