Apple River Flowage Lake vs South Twin Lake
Water quality, depth, fish species, and recreation comparison.
South Twin Lake has a higher water quality grade (A, Excellent) than Apple River Flowage Lake (D, Poor). Both are in Polk County, Wisconsin.
Both Apple River Flowage Lake and South Twin 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. South Twin Lake (A) is materially cleaner than Apple River Flowage Lake (D). 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 — South Twin 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?
Apple River Flowage Lake
Murky, only visible to about 5.9 ft.
South Twin Lake
No clarity data.
Side-by-Side Metrics
| Metric | Apple River Flowage Lake | South Twin Lake |
|---|---|---|
| Overall Grade | D (Poor) | A (Excellent) |
| Water Clarity | 5.9 ft | No data |
| Phosphorus | 78.5 µg/L | 11.7 µg/L |
| Chlorophyll-a (Algae) | No data | No data |
| Maximum Depth | - | - |
| Surface Area | 639 acres | 639 acres |
| Public Access | Unknown | Unknown |
| Fish Species | 0 | 0 |
| Trophic State | eutrophic | oligotrophic |
Bold value = better for that metric (lower phosphorus / chlorophyll = cleaner; higher Secchi / depth / species count = better).
Verdict
South Twin Lake wins on overall water quality with a Grade A versus Apple River Flowage Lake's Grade D. For fishing diversity, South Twin Lake also leads with 0 species.