Birch Lake vs Ottertrack Lake
Water quality, depth, fish species, and recreation comparison.
Birch Lake and Ottertrack Lake both received the same overall water quality grade of A (Excellent). Both are in Unknown County, Minnesota.
Both Birch Lake and Ottertrack 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 — Birch Lake (A) versus Ottertrack 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.
Birch Lake
Crystal clear, you can see 15 ft down.
Ottertrack Lake
Crystal clear, you can see 20.7 ft down.
Side-by-Side Metrics
| Metric | Birch Lake | Ottertrack Lake |
|---|---|---|
| Overall Grade | A (Excellent) | A (Excellent) |
| Water Clarity | 15 ft | 20.7 ft |
| Phosphorus | No data | No data |
| Chlorophyll-a (Algae) | No data | No data |
| Maximum Depth | 34 ft | 116 ft |
| Surface Area | 836.35 acres | 1.1K acres |
| Public Access | No | No |
| 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
Both lakes earn the same Grade A. The tiebreakers come down to clarity (Birch Lake: 15 ft, Ottertrack Lake: 20.7 ft) and what you want from the lake. Birch Lake matches its peer on species count.