How Clean Is Three Island Lake?
Three Island Lake is among the cleanest lakes in Minnesota. It received a water quality grade of A (Excellent) based on EPA monitoring data. Water clarity (Secchi depth): 12 ft. Phosphorus: 17 µg/L. Trophic State Index: 43.
Cleanliness Snapshot
| Metric | Three Island Lake | Minnesota avg |
|---|---|---|
| Overall Grade | A | C |
| Water Clarity (Secchi) | 12 ft | — |
| Phosphorus | 17 µg/L | <30 = clean |
| Trophic State Index | 43 | <50 = clean |
How does Three Island Lake compare?
Three Island Lake's grade of A matches or beats the Minnesota state average of C. It ranks #40 of 86 lakes in Beltrami County by water quality score. Multi-year monitoring data shows water quality is improving based on 5 years of records.