Long Lake vs Minong Flowage Lake
Water quality, depth, fish species, and recreation comparison.
Long Lake has a higher water quality grade (B, Good) than Minong Flowage Lake (C, Fair). Both are in Washburn County, Wisconsin.
Both Long Lake and Minong Flowage Lake sit in Wisconsin. 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. The grades are close: Long Lake (B) and Minong Flowage Lake (C) 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.
Long Lake
Moderate clarity, visible to about 9.5 ft.
Minong Flowage Lake
Murky, only visible to about 3.5 ft.
Side-by-Side Metrics
| Metric | Long Lake | Minong Flowage Lake |
|---|---|---|
| Overall Grade | B (Good) | C (Fair) |
| Water Clarity | 9.5 ft | 3.5 ft |
| Phosphorus | 17.3 µg/L | 37.2 µg/L |
| Chlorophyll-a (Algae) | No data | No data |
| Maximum Depth | - | 21 ft |
| Surface Area | 3,290 acres | 1,587 acres |
| Public Access | Yes | Yes |
| Fish Species | 0 | 5 |
| Trophic State | mesotrophic | eutrophic |
Bold value = better for that metric (lower phosphorus / chlorophyll = cleaner; higher Secchi / depth / species count = better).
Verdict
Long Lake wins on overall water quality with a Grade B versus Minong Flowage Lake's Grade C. Water clarity: 9.5 ft vs 3.5 ft. For more fish-species variety, Minong Flowage Lake edges ahead with 5 documented species.
Source: EPA National Aquatic Resource Surveys, 2026.