Big Sandy Lake vs Clear Lake
Water quality, depth, fish species, and recreation comparison.
Clear Lake has a higher water quality grade (A, Excellent) than Big Sandy Lake (C, Fair). Both are in Aitkin County, Minnesota.
Big Sandy Lake and Clear Lake 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: Clear Lake grades a A while Big Sandy Lake grades a C. 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 — Clear 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 Sandy Lake
Murky, only visible to about 4.5 ft.
Clear Lake
Crystal clear, you can see 15 ft down.
Side-by-Side Metrics
| Metric | Big Sandy Lake | Clear Lake |
|---|---|---|
| Overall Grade | C (Fair) | A (Excellent) |
| Water Clarity | 4.5 ft | 15 ft |
| Phosphorus | 29.5 µg/L | 15 µg/L |
| Chlorophyll-a (Algae) | No data | No data |
| Maximum Depth | 84 ft | 24 ft |
| Surface Area | 6.1K acres | 573.5 acres |
| Public Access | Yes | Yes |
| Fish Species | 22 | 14 |
| Trophic State | eutrophic | mesotrophic |
Bold value = better for that metric (lower phosphorus / chlorophyll = cleaner; higher Secchi / depth / species count = better).
Verdict
Clear Lake wins on overall water quality with a Grade A versus Big Sandy Lake's Grade C. Water clarity: 15 ft vs 4.5 ft. For more fish-species variety, Big Sandy Lake edges ahead with 22 documented species.