Lake 37 vs Lake St. Louis
Water quality, depth, fish species, and recreation comparison.
Lake 37 has a higher water quality grade (B, Good) than Lake St. Louis (D, Poor). Both are in St. Charles County, Wisconsin.
Lake 37 and Lake St. Louis are both in Missouri — 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. Lake 37 (B) is materially cleaner than Lake St. Louis (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 — Lake 37 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?
Lake 37
Murky, only visible to about 4 ft.
Lake St. Louis
Very murky, less than 2.7 ft of visibility.
Side-by-Side Metrics
| Metric | Lake 37 | Lake St. Louis |
|---|---|---|
| Overall Grade | B (Good) | D (Poor) |
| Water Clarity | 4 ft | 2.7 ft |
| Phosphorus | 16 µg/L | 50 µg/L |
| Chlorophyll-a (Algae) | 7.2 µg/L | 74.3 µg/L |
| Maximum Depth | - | - |
| Surface Area | 30 acres | 563 acres |
| Public Access | Unknown | Unknown |
| Fish Species | 0 | 0 |
| Trophic State | eutrophic | eutrophic |
Bold value = better for that metric (lower phosphorus / chlorophyll = cleaner; higher Secchi / depth / species count = better).
Verdict
Lake 37 wins on overall water quality with a Grade B versus Lake St. Louis's Grade D. Water clarity: 4 ft vs 2.7 ft. For fishing diversity, Lake 37 also leads with 0 species.