Mercer County Lake Quality
Pennsylvania, 4 lakes, measured by PA DEP
Mercer County holds 4 monitored lakes. With a sample that small the county-level summary describes those specific waters, not necessarily every water body in the county. 1 of those lake carry recent nutrient and algae readings. The county-level summary describes that subset, not every water body listed. Phosphorus and algae readings vary widely across Mercer County; the per-lake pages below carry the numbers.
The county's lakes lean shallow, which makes the readings sensitive to wind, sediment-resuspension, and any nutrient inputs from the watershed. The cleanest measured lake is Shenango River Lake.
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Quick Answers for Mercer County
Planning a trip? Check special fishing regulations for Shenango River Lake — or check the official Pennsylvania fishing regulations.
All Lakes in Mercer County
4 lakes · 1 ranked on readings, 3 without enough sampling1 lake ranked on readings · 3 without enough sampling, hidden
| # | Lake | Clarity | Phosphorus | Algae | Trophic | Max Depth | Access |
|---|---|---|---|---|---|---|---|
| 1 | Shenango River LakeMercer | No recent samples | 82.5 µg/L | 19.1 µg/L | No recent samples | No recent samples | ✓ Public |
| Lake WilhelmMercer | No recent samples | No recent samples | No recent samples | No recent samples | 24 ft | ✓ Public | |
| Sandy LakeMercer | No recent samples | No recent samples | No recent samples | No recent samples | No recent samples | Not recorded | |
| Lake LatonkaMercer | No recent samples | No recent samples | No recent samples | No recent samples | No recent samples | Not recorded |
NR = no nutrient or algae reading on record. The measurements are published as the authority reports them. Where the data comes from.
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Source: the Pennsylvania Department of Environmental Protection. See data sources.