Is Three Island Lake Safe for Swimming?
Three Island Lake in Beltrami County, Minnesota has a water quality grade of A (Excellent). Excellent for swimming, crystal clear water with minimal algae. Water clarity: 12 ft visibility. Phosphorus: 17 µg/L. Always check local health department advisories before swimming.
Key Metrics
| Metric | Value |
|---|---|
| Overall Grade | A (Excellent) |
| Water Clarity (Secchi Depth) | 12 ft |
| Phosphorus | 17 μg/L |
| Maximum Depth | 25 ft |
| Location | Beltrami County, Minnesota |
How does Three Island Lake compare?
With an overall water quality grade of A, Three Island Lake matches or beats the Minnesota state average of Grade C. It ranks #40 of 86 lakes in Beltrami County by water quality score.
Water clarity (Secchi depth) sits at 12 feet. That counts as exceptional clarity — sunlight penetrates deep, supporting submerged plants and limiting algae.