
Seneca County Lake Quality
New York, 4 lakes, measured by NY DEC
Seneca County has 4 monitored lakes — a thin enough sample that one or two stressed lakes can move the county average noticeably. Use the per-lake pages below for what actually matters. 1 of those lake carry recent nutrient and algae readings. The county-level summary describes that subset, not every water body listed. On average, Seneca County lakes carry some of the lowest phosphorus and chlorophyll-a readings in New York, with clear summer transparency across most monitored basins.
Most of the county's monitored lakes are shallow, under 50 feet, which means wind keeps the water column mixed all summer and sediment-bound phosphorus releases back into the surface layer whenever the bottom is disturbed. Seneca Lake Platform has the lowest nutrient and algae readings in the county.
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Quick Answers for Seneca County
Planning a trip? Check special fishing regulations for Seneca Lake Platform — or check the official New York fishing regulations.
All Lakes in Seneca 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 | Access |
|---|---|---|---|---|---|---|
| 1 | Seneca Lake PlatformSeneca | 11.5 ft | 8 µg/L | 2.8 µg/L | No recent samples | ✓ Public |
| Gem LakeSeneca | No recent samples | No recent samples | No recent samples | No recent samples | Not recorded | |
| Black LakeSeneca | No recent samples | No recent samples | No recent samples | No recent samples | Not recorded | |
| Van Cleef LakeSeneca | 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 New York Department of Environmental Conservation. See data sources.