Minnetonka Lake vs Minnewashta Lake
Water quality, depth, fish species, and recreation comparison.
Minnewashta Lake has a higher water quality grade (A, Excellent) than Minnetonka Lake (C, Fair). Both are in Minnesota.
Minnetonka Lake and Minnewashta 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: Minnewashta Lake grades a A while Minnetonka 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 — Minnewashta 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?
Minnetonka Lake
Good clarity, visible to about 10 ft.
Minnewashta Lake
Good clarity, visible to about 11.5 ft.
Side-by-Side Metrics
| Metric | Minnetonka Lake | Minnewashta Lake |
|---|---|---|
| Overall Grade | C (Fair) | A (Excellent) |
| Water Clarity | 10 ft | 11.5 ft |
| Phosphorus | 28 µg/L | 14 µg/L |
| Chlorophyll-a (Algae) | 10.1 µg/L | 2.3 µg/L |
| Maximum Depth | 113 ft | 70 ft |
| Surface Area | 14,206 acres | 680 acres |
| Public Access | Yes | Yes |
| Fish Species | 18 | 14 |
| Trophic State | mesotrophic | mesotrophic |
Bold value = better for that metric (lower phosphorus / chlorophyll = cleaner; higher Secchi / depth / species count = better).
Verdict
Minnewashta Lake wins on overall water quality with a Grade A versus Minnetonka Lake's Grade C. Water clarity: 11.5 ft vs 10 ft. For more fish-species variety, Minnetonka Lake edges ahead with 18 documented species.
Source: EPA National Aquatic Resource Surveys, 2026.