Delaware County Lake Quality
New York, 1 lakes, average grade A (Excellent)
Delaware County has 1 graded 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. On average, Delaware County lakes grade an A. That puts it near the top of the New York county ranking.
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. Somerset Lake (A) is the cleanest in the county.
Quick Answers for Delaware County
Planning a trip? Check special fishing regulations for Somerset Lake — or check the official New York fishing regulations.
All Lakes in Delaware County
| Rank | Lake | Grade | Clarity | Phosphorus |
|---|---|---|---|---|
| 1 | Somerset Lake | A | 15.1 ft | - |
Other Counties in New York
See how Delaware County stacks up in the national county water-quality rankings, or browse the full directory of graded lakes across all 16 states.
Where to stay near Delaware County
Top-rated places to stay near Delaware County
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Source: EPA National Aquatic Resource Surveys, 2026.