Nelson Lake vs Oldham Lake
Water quality, depth, fish species, and recreation comparison.
Oldham Lake has a higher water quality grade (C, Fair) than Nelson Lake (D, Poor). Both are in Wisconsin.
Both Nelson Lake and Oldham Lake sit in Iowa. 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. The grades are close: Nelson Lake (D) and Oldham Lake (C) 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.
Nelson Lake
Murky, only visible to about 3.8 ft.
Oldham Lake
Murky, only visible to about 5.1 ft.
Side-by-Side Metrics
| Metric | Nelson Lake | Oldham Lake |
|---|---|---|
| Overall Grade | D (Poor) | C (Fair) |
| Water Clarity | 3.8 ft | 5.1 ft |
| Phosphorus | No data | No data |
| Chlorophyll-a (Algae) | 30.6 µg/L | 8.5 µg/L |
| Maximum Depth | - | - |
| Surface Area | 11 acres | 16.1 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
Oldham Lake wins on overall water quality with a Grade C versus Nelson Lake's Grade D. Water clarity: 5.1 ft vs 3.8 ft. For fishing diversity, Oldham Lake also leads with 0 species.