Jewett Lake vs Long Lake
Water quality, depth, fish species, and recreation comparison.
Jewett Lake and Long Lake both received the same overall water quality grade of A (Excellent). Both are in Otter Tail County, Minnesota.
Jewett Lake and Long 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. These two are within a letter of each other on the rubric — Jewett Lake (A) versus Long 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.
Jewett Lake
Crystal clear, you can see 17.7 ft down.
Long Lake
Good clarity, visible to about 11.6 ft.
Side-by-Side Metrics
| Metric | Jewett Lake | Long Lake |
|---|---|---|
| Overall Grade | A (Excellent) | A (Excellent) |
| Water Clarity | 17.7 ft | 11.6 ft |
| Phosphorus | 15 µg/L | 17 µg/L |
| Chlorophyll-a (Algae) | 2.9 µg/L | 3.9 µg/L |
| Maximum Depth | 75 ft | 73 ft |
| Surface Area | 747 acres | 767 acres |
| Public Access | Yes | Yes |
| Fish Species | 13 | 17 |
| Trophic State | oligotrophic | mesotrophic |
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 (Jewett Lake: 17.7 ft, Long Lake: 11.6 ft) and what you want from the lake. Jewett Lake has fewer fish species than Long Lake.
Source: EPA National Aquatic Resource Surveys, 2026.