Delavan Lake vs Outlet To Lake Geneva
Water quality, depth, fish species, and recreation comparison.
Delavan Lake has a higher water quality grade (C, Fair) than Outlet To Lake Geneva (D, Poor). Both are in Walworth County, Wisconsin.
Delavan Lake and Outlet To Lake Geneva are both in Wisconsin — 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. The grades are close: Delavan Lake (C) and Outlet To Lake Geneva (D) 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.
Delavan Lake
Moderate clarity, visible to about 8.9 ft.
Outlet To Lake Geneva
No clarity data.
Side-by-Side Metrics
| Metric | Delavan Lake | Outlet To Lake Geneva |
|---|---|---|
| Overall Grade | C (Fair) | D (Poor) |
| Water Clarity | 8.9 ft | No data |
| Phosphorus | 52.5 µg/L | 658 µg/L |
| Chlorophyll-a (Algae) | 9.1 µg/L | No data |
| Maximum Depth | 52 ft | 135 ft |
| Surface Area | 1,906 acres | 5,401 acres |
| Public Access | Yes | Yes |
| Fish Species | 6 | 6 |
| Trophic State | eutrophic | hypereutrophic |
Bold value = better for that metric (lower phosphorus / chlorophyll = cleaner; higher Secchi / depth / species count = better).
Verdict
Delavan Lake wins on overall water quality with a Grade C versus Outlet To Lake Geneva's Grade D. For fishing diversity, Delavan Lake also leads with 6 species.
Source: EPA National Aquatic Resource Surveys, 2026.