Otter Tail Lake vs Walker Lake
Water quality, depth, fish species, and recreation comparison.
Otter Tail Lake has a higher water quality grade (A, Excellent) than Walker Lake (C, Fair). Both are in Otter Tail County, Minnesota.
Both Otter Tail Lake and Walker 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. Otter Tail Lake (A) is materially cleaner than Walker Lake (C). A gap that wide is unlikely to close in a single year of remediation work; it reflects multi-decade differences in the lakes themselves.
For a recreational visitor, the wider grade gap is decisive — Otter Tail 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?
Otter Tail Lake
Good clarity, visible to about 12.1 ft.
Walker Lake
Moderate clarity, visible to about 7.5 ft.
Side-by-Side Metrics
| Metric | Otter Tail Lake | Walker Lake |
|---|---|---|
| Overall Grade | A (Excellent) | C (Fair) |
| Water Clarity | 12.1 ft | 7.5 ft |
| Phosphorus | 16 µg/L | 26.5 µg/L |
| Chlorophyll-a (Algae) | 5.5 µg/L | 8.3 µg/L |
| Maximum Depth | 120 ft | 29 ft |
| Surface Area | 14,079 acres | 578 acres |
| Public Access | Yes | Yes |
| Fish Species | 17 | 0 |
| Trophic State | mesotrophic | eutrophic |
Bold value = better for that metric (lower phosphorus / chlorophyll = cleaner; higher Secchi / depth / species count = better).
Verdict
Otter Tail Lake wins on overall water quality with a Grade A versus Walker Lake's Grade C. Water clarity: 12.1 ft vs 7.5 ft. For fishing diversity, Otter Tail Lake also leads with 17 species.
Source: EPA National Aquatic Resource Surveys, 2026.