Old Reservoir vs Thomas Hill Res. Nr. Dam Lake
Water quality, depth, fish species, and recreation comparison.
Old Reservoir has a higher water quality grade (C, Fair) than Thomas Hill Res. Nr. Dam Lake (D, Poor). Both are in Randolph County, Wisconsin.
Both Old Reservoir and Thomas Hill Res. Nr. Dam Lake sit in Missouri. 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 — Old Reservoir (C) versus Thomas Hill Res. Nr. Dam Lake (D). 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.
Old Reservoir
Murky, only visible to about 3.6 ft.
Thomas Hill Res. Nr. Dam Lake
Very murky, less than 2.3 ft of visibility.
Side-by-Side Metrics
| Metric | Old Reservoir | Thomas Hill Res. Nr. Dam Lake |
|---|---|---|
| Overall Grade | C (Fair) | D (Poor) |
| Water Clarity | 3.6 ft | 2.3 ft |
| Phosphorus | 33 µg/L | 61 µg/L |
| Chlorophyll-a (Algae) | 14.2 µg/L | 14.2 µg/L |
| Maximum Depth | - | - |
| Surface Area | 21 acres | 3.5K 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
Old Reservoir wins on overall water quality with a Grade C versus Thomas Hill Res. Nr. Dam Lake's Grade D. Water clarity: 3.6 ft vs 2.3 ft. For fishing diversity, Old Reservoir also leads with 0 species.