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LakeQuality
Late afternoon sun over Slim Lake, scattering a bright path across wind-textured water

Ulster County Lake Quality

New York, 25 lakes, measured by NY DEC

There are 25 monitored lakes in Ulster County. The mix is varied enough that the county-level average tells you the broad strokes, not the choose-this-cabin specifics. The 25 monitored lakes in Ulster County carry whatever clarity, phosphorus, and chlorophyll-a readings NY DEC has published, shown as reported.

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.

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Where to stay near Ulster County

Top-rated places to stay near Ulster County

Prices for Oct 16–18, 4 adults. Change dates on the map below.

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Quick Answers for Ulster County

Cleanest lakes in Ulster County →Cleanest lakes in New York →Best swimming lakes in New York →

Planning a trip? Check special fishing regulations for Tillson Lake — or check the official New York fishing regulations.

All Lakes in Ulster County

25 lakes · 0 ranked on readings, 25 without enough sampling0 lakes ranked on readings · 25 without enough sampling, hidden

#LakeClarityPhosphorusAlgaeTrophicMax DepthAccess
Tillson LakeUlsterNo recent samplesNo recent samplesNo recent samplesNo recent samplesNo recent samplesNot recorded
Lake MaratanzaUlsterNo recent samplesNo recent samplesNo recent samplesNo recent samplesNo recent samplesNot recorded
Ulster Heights LakeUlsterNo recent samplesNo recent samplesNo recent samplesNo recent samplesNo recent samplesNot recorded
Cape PondUlsterNo recent samplesNo recent samplesNo recent samplesNo recent samples14.1 ftNot recorded
Lake AwostingUlsterNo recent samplesNo recent samplesNo recent samplesNo recent samples80.4 ftNot recorded
Lake MinnewaskaUlsterNo recent samplesNo recent samplesNo recent samplesNo recent samples62.3 ftNot recorded
Honk LakeUlsterNo recent samplesNo recent samplesNo recent samplesNo recent samplesNo recent samplesNot recorded
Lyon LakeUlsterNo recent samplesNo recent samplesNo recent samplesNo recent samplesNo recent samplesNot recorded
Lyonsville PondUlsterNo recent samplesNo recent samplesNo recent samplesNo recent samplesNo recent samplesNot recorded
Rondout ReservoirUlsterNo recent samplesNo recent samplesNo recent samplesNo recent samples120.1 ftNot recorded
Ashokan ReservoirUlsterNo recent samplesNo recent samplesNo recent samplesNo recent samplesNo recent samplesNot recorded
Fourth LakeUlsterNo recent samplesNo recent samplesNo recent samplesNo recent samplesNo recent samplesNot recorded
Third LakeUlsterNo recent samplesNo recent samplesNo recent samplesNo recent samplesNo recent samplesNot recorded
Ashokan ReservoirUlsterNo recent samplesNo recent samplesNo recent samplesNo recent samples184.4 ftNot recorded
Kenozia LakeUlsterNo recent samplesNo recent samplesNo recent samplesNo recent samplesNo recent samplesNot recorded
Yankeetown PondUlsterNo recent samplesNo recent samplesNo recent samplesNo recent samplesNo recent samplesNot recorded
Lake KatrineUlsterNo recent samplesNo recent samplesNo recent samplesNo recent samplesNo recent samplesNot recorded
Esopus LakeUlsterNo recent samplesNo recent samplesNo recent samplesNo recent samplesNo recent samplesNot recorded
Sturgeon PoolUlsterNo recent samplesNo recent samplesNo recent samplesNo recent samples93 ftNot recorded
Mirror LakeUlsterNo recent samplesNo recent samplesNo recent samplesNo recent samplesNo recent samplesNot recorded
Fifth LakeUlsterNo recent samplesNo recent samplesNo recent samplesNo recent samplesNo recent samplesNot recorded
Heddens LakeUlsterNo recent samplesNo recent samplesNo recent samplesNo recent samplesNo recent samplesNot recorded
Chodikee LakeUlsterNo recent samplesNo recent samplesNo recent samplesNo recent samplesNo recent samplesNot recorded
Cooper LakeUlsterNo recent samplesNo recent samplesNo recent samplesNo recent samplesNo recent samplesNot recorded
Alder LakeUlsterNo recent samplesNo recent samplesNo recent samplesNo recent samples22 ftNot 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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Other Counties in New York

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Browse every New York lake, or the full directory of lakes across all United States (49 states), Canada (Ontario, Québec, Nova Scotia, British Columbia and Newfoundland and Labrador), and 38 other country hubs..

Source: the New York Department of Environmental Conservation. See data sources.