Lake Poygan vs Little Lake Butte des Morts
Water quality, depth, fish species, and recreation comparison.
Lake Poygan and Little Lake Butte des Morts both received the same overall water quality grade of F (Very Poor). Both are in Winnebago County, Wisconsin.
Both Lake Poygan and Little Lake Butte des Morts 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. These two are within a letter of each other on the rubric — Lake Poygan (F) versus Little Lake Butte des Morts (F). 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.
Lake Poygan
Very murky, less than 2.5 ft of visibility.
Little Lake Butte des Morts
Very murky, less than 2 ft of visibility.
Side-by-Side Metrics
| Metric | Lake Poygan | Little Lake Butte des Morts |
|---|---|---|
| Overall Grade | F (Very Poor) | F (Very Poor) |
| Water Clarity | 2.5 ft | 2 ft |
| Phosphorus | No data | 133.5 µg/L |
| Chlorophyll-a (Algae) | No data | No data |
| Maximum Depth | 11 ft | 18 ft |
| Surface Area | 14.0K acres | 1.2K acres |
| Public Access | Unknown | Unknown |
| Fish Species | 0 | 0 |
| Trophic State | eutrophic | hypereutrophic |
Bold value = better for that metric (lower phosphorus / chlorophyll = cleaner; higher Secchi / depth / species count = better).
Verdict
Both lakes earn the same Grade F. The tiebreakers come down to clarity (Lake Poygan: 2.5 ft, Little Lake Butte des Morts: 2 ft) and what you want from the lake. Lake Poygan matches its peer on species count.