Big Lake vs Upper Red Lake: East
Water quality, depth, fish species, and recreation comparison.
Big Lake has a higher water quality grade (A, Excellent) than Upper Red Lake: East (D, Poor). Both are in Beltrami County, Minnesota.
Big Lake and Upper Red Lake: East are both in Minnesota — a same-state head-to-head where the comparison comes down to lake-specific differences in depth, watershed, and monitoring history rather than the broader state-level water-quality regime. The grades are meaningfully apart: Big Lake grades a A while Upper Red Lake: East grades a D. That two-letter spread reflects real underlying differences — different watershed inputs, different depth profiles, or different monitoring rigor.
For a recreational visitor, the wider grade gap is decisive — Big Lake is the better water-quality choice. For a researcher, the gap is the interesting part: what is different about the two watersheds, and which of those differences is mutable?
Big Lake
Moderate clarity, visible to about 9.7 ft.
Upper Red Lake: East
Very murky, less than 2 ft of visibility.
Side-by-Side Metrics
| Metric | Big Lake | Upper Red Lake: East |
|---|---|---|
| Overall Grade | A (Excellent) | D (Poor) |
| Water Clarity | 9.7 ft | 2 ft |
| Phosphorus | 15 µg/L | 37 µg/L |
| Chlorophyll-a (Algae) | 4.8 µg/L | 13 µg/L |
| Maximum Depth | 35 ft | 15 ft |
| Surface Area | 3,598 acres | 119,294 acres |
| Public Access | Yes | No |
| Fish Species | 17 | 15 |
| Trophic State | mesotrophic | eutrophic |
Bold value = better for that metric (lower phosphorus / chlorophyll = cleaner; higher Secchi / depth / species count = better).
Verdict
Big Lake wins on overall water quality with a Grade A versus Upper Red Lake: East's Grade D. Water clarity: 9.7 ft vs 2 ft. For fishing diversity, Big Lake also leads with 17 species.
Source: EPA National Aquatic Resource Surveys, 2026.