Beltrami Lake vs Big Lake
Water quality, depth, fish species, and recreation comparison.
Beltrami Lake and Big Lake read the same on nutrients and algae. Both are in Beltrami County, Minnesota.
Both Beltrami Lake and Big Lake sit in Minnesota. A same-state comparison strips out the state-level water-quality regime as a variable: any differences in the readings here are about the lakes themselves, not the agencies sampling them. The readings are close: Beltrami Lake and Big Lake sit within a narrow band of each other on phosphorus, chlorophyll-a and clarity. The per-parameter table below shows where the small differences actually live.
With readings 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 11.2 ft.
Big Lake
Moderate clarity, visible to about 9.7 ft.
Side-by-Side Metrics
| Metric | Beltrami Lake | Big Lake |
|---|---|---|
| Water Clarity | 11.2 ft Better | 9.7 ft |
| Phosphorus | 15 µg/L | 15 µg/L |
| Chlorophyll-a (Algae) | 4.3 µg/L Better | 4.8 µg/L |
| Maximum Depth | 50 ft Better | 35 ft |
| Surface Area | 726 acres | 3,598 acres |
| Public Access | Yes | Yes |
| Fish Species | 16 | 17 Better |
| Trophic State | mesotrophic | mesotrophic |
A green ✓ marks the better value for that metric (lower phosphorus / chlorophyll = cleaner; higher Secchi / depth / species count = better). Surface area and trophic state carry no tick — a bigger lake is not a better lake.
Swap a lake
Compare Beltrami Lake or Big Lake against a different lake.
Verdict
Both lakes earn the same Grade A. The tiebreakers come down to clarity (Beltrami Lake: 11.2 ft, Big Lake: 9.7 ft) and what you want from the lake. Beltrami Lake has fewer fish species than Big Lake.
Source: EPA National Aquatic Resource Surveys, 2026.