Delavan Lake vs Lake Beulah
Water quality, depth, fish species, and recreation comparison.
Lake Beulah reads lower on nutrients and algae than Delavan Lake. Both are in Walworth County, Wisconsin.
Both Delavan Lake and Lake Beulah sit in Wisconsin. A same-state comparison strips out the state-level water-quality regime as a variable: any differences in the readings here are about the lakes themselves, not the agencies sampling them. The readings are meaningfully apart: Lake Beulah carries clearly lower phosphorus and chlorophyll-a readings than Delavan Lake. A spread that wide reflects real underlying differences, in watershed inputs, depth profiles, or monitoring rigor.
For a recreational visitor, the wider gap in the readings is decisive: Lake Beulah has the lower nutrient and algae numbers. For a researcher, the gap is the interesting part: what is different about the two watersheds, and which of those differences is mutable?
Delavan Lake
Moderate clarity, visible to about 8.9 ft.
Lake Beulah
Good clarity, visible to about 10 ft.
Side-by-Side Metrics
| Metric | Delavan Lake | Lake Beulah |
|---|---|---|
| Water Clarity | 8.9 ft | 10 ft Better |
| Phosphorus | 52.5 µg/L | 13.4 µg/L Better |
| Chlorophyll-a (Algae) | 9.1 µg/L | 2.5 µg/L Better |
| Maximum Depth | 52 ft | 58 ft Better |
| Surface Area | 1,906 acres | 812 acres |
| Public Access | Yes | Yes |
| Fish Species | 6 Better | 3 |
| Trophic State | eutrophic | mesotrophic |
A green ✓ marks the better value for that metric (lower phosphorus / chlorophyll = cleaner; higher Secchi / depth / species count = better). Surface area and trophic state carry no tick — a bigger lake is not a better lake.
Swap a lake
Compare Delavan Lake or Lake Beulah against a different lake.
Verdict
Lake Beulah reads lower on nutrients and algae than Delavan Lake. Water clarity: 10 ft vs 8.9 ft. For more fish-species variety, Delavan Lake edges ahead with 6 documented species.
Source: EPA National Aquatic Resource Surveys, 2026.