Birch Lake vs Stony Lake
Water quality, depth, fish species, and recreation comparison.
Stony Lake has a higher water quality grade (A, Excellent) than Birch Lake (A, Excellent). Both are in Cass County, Minnesota.
Birch Lake and Stony 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 close: Birch Lake (A) and Stony Lake (A) are within one letter of each other on the LakeGrade rubric. The per-parameter sub-grades below will show where the small differences actually live.
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.
Birch Lake
Good clarity, visible to about 13.7 ft.
Stony Lake
Crystal clear, you can see 23.3 ft down.
Side-by-Side Metrics
| Metric | Birch Lake | Stony Lake |
|---|---|---|
| Overall Grade | A (Excellent) | A (Excellent) |
| Water Clarity | 13.7 ft | 23.3 ft |
| Phosphorus | 12 µg/L | 7 µg/L |
| Chlorophyll-a (Algae) | No data | No data |
| Maximum Depth | 45 ft | 50 ft |
| Surface Area | 1.3K acres | 563.21 acres |
| Public Access | Yes | Yes |
| Fish Species | 1 | 1 |
| Trophic State | oligotrophic | oligotrophic |
Bold value = better for that metric (lower phosphorus / chlorophyll = cleaner; higher Secchi / depth / species count = better).
Verdict
Stony Lake wins on overall water quality with a Grade A versus Birch Lake's Grade A. Water clarity: 23.3 ft vs 13.7 ft. For fishing diversity, Stony Lake also leads with 1 species.