Beltrami Lake vs Three Island Lake
Water quality, depth, fish species, and recreation comparison.
Beltrami Lake and Three Island Lake both received the same overall water quality grade of A (Excellent). Both are in Beltrami County, Minnesota.
Both Beltrami Lake and Three Island Lake sit in Minnesota. A same-state comparison strips out the state-level water-quality regime as a variable: any grade differences here are about the lakes themselves, not the agencies grading them. These two are within a letter of each other on the rubric — Beltrami Lake (A) versus Three Island Lake (A). The deciding factors for a recreational visitor are likely physical (depth, access, fish species) rather than water-quality differences.
With grades this close, the choice between the two lakes turns on non-water-quality factors: depth, fish species, public access, distance from home. The per-lake pages below cover all of those.
Beltrami Lake
Good clarity, visible to about 11 ft.
Three Island Lake
Good clarity, visible to about 12 ft.
Side-by-Side Metrics
| Metric | Beltrami Lake | Three Island Lake |
|---|---|---|
| Overall Grade | A (Excellent) | A (Excellent) |
| Water Clarity | 11 ft | 12 ft |
| Phosphorus | 15 µg/L | 17 µg/L |
| Chlorophyll-a (Algae) | No data | No data |
| Maximum Depth | 50 ft | 25 ft |
| Surface Area | 725.82 acres | 729.49 acres |
| Public Access | Yes | Yes |
| Fish Species | 1 | 1 |
| Trophic State | mesotrophic | mesotrophic |
Bold value = better for that metric (lower phosphorus / chlorophyll = cleaner; higher Secchi / depth / species count = better).
Verdict
Both lakes earn the same Grade A. The tiebreakers come down to clarity (Beltrami Lake: 11 ft, Three Island Lake: 12 ft) and what you want from the lake. Beltrami Lake matches its peer on species count.