Impaired Lakes in New York
97 of 180 graded New York lakes (54%) are officially listed as impaired under Clean Water Act §303(d) in the most recent EPA ATTAINS reporting cycle. 35 have an approved TMDL restoration plan.
Top Causes of Impairment in New York
Reading the New York impairment landscape
54% of New York's tracked lakes — 97 of 180 — appear on the EPA Clean Water Act §303(d) impaired-waters list. At that share, impairment is the default state rather than an exception: the majority of lakes are flagged for at least one pollutant exceeding water-quality standards. Trip-planning for clean water in New York typically requires checking impairment status as a first filter, not as an edge case.
The leading impairment category in New York is Nutrients (phosphorus, nitrogen) — nutrient enrichment, typically from agricultural fertilizer runoff, septic discharge, or stormwater carrying lawn-care residue. Nutrient-impaired lakes can still be safe for contact recreation in many conditions, but they're prone to algal blooms (including potentially toxic cyanobacteria) during warm-water periods. Check the state's beach-monitoring or harmful-algal-bloom dashboard before swimming on nutrient-impaired waters in summer.
Impaired-waters listings come from the state environmental agency's §303(d) submission to EPA, refreshed on a roughly 2-year cycle. A listed lake stays on the list until either a TMDL is established and the cleanup completes, or subsequent monitoring shows the pollutant concentrations no longer exceed water-quality standards. The list below reflects the most recent available New York submission to the EPA Assessment, Total Maximum Daily Load Tracking and Implementation System (ATTAINS) dataset.
All 97 EPA-Listed Impaired Lakes in New York
| Lake | County | Grade | Causes | TMDL |
|---|---|---|---|---|
| West Pond | Herkimer | A | pH / acidity | — |
| Squash Pond | Herkimer | A | pH / acidity, Salinity / chlorides | ✓ |
| Willys Lake | Herkimer | A | pH / acidity | ✓ |
| Windfall Pond | Herkimer | A | pH / acidity | ✓ |
| Loon Hollows Pond | Herkimer | A | pH / acidity | ✓ |
| Barnes Lake | Lewis | B | pH / acidity | — |
| Main Section Lake | Clinton | C | Mercury, Nutrients (phosphorus, nitrogen), PCBs | ✓ |
| Little Clear Pond | Franklin | C | pH / acidity | ✓ |
| Grass Pond | Franklin | C | pH / acidity | ✓ |
| Irondequoit Bay Lake | Monroe | D | Pesticides, PCBs | — |
| Blue Mountain Lake | Hamilton | NR | Mercury | ✓ |
| Brant Lake | Warren | NR | Oxygen depletion (low DO) | — |
| Sodus Bay Lake | Wayne | NR | Nutrients (phosphorus, nitrogen) | — |
| Honeoye Lake | Ontario | NR | Nutrients (phosphorus, nitrogen), Oxygen depletion (low DO) | ✓ |
| Lime Lake | Cattaraugus | NR | Nutrients (phosphorus, nitrogen) | — |
| Pleasure Lake | Sullivan | NR | Nutrients (phosphorus, nitrogen) | — |
| Fresh Pond | Suffolk | NR | Nutrients (phosphorus, nitrogen) | — |
| Palmer Lake | Putnam | NR | Nutrients (phosphorus, nitrogen) | ✓ |
| Conesus Lake | Livingston | NR | Nutrients (phosphorus, nitrogen), Oxygen depletion (low DO) | ✓ |
| Schroon Lake | Essex | NR | Mercury | ✓ |
| Duck Lake | Cayuga | NR | Nutrients (phosphorus, nitrogen) | — |
| Sepasco Lake | Dutchess | NR | Nutrients (phosphorus, nitrogen) | — |
| Taconic Pond | Rensselaer | NR | Mercury | ✓ |
| Orange Lake | Orange | NR | Nutrients (phosphorus, nitrogen) | — |
| Eagle Pond | Franklin | NR | pH / acidity | — |
| Cossayuna Lake | Washington | NR | Nutrients (phosphorus, nitrogen) | ✓ |
| Lake Como | Cayuga | NR | Nutrients (phosphorus, nitrogen) | — |
| Lake Lincolndale | Westchester | NR | Nutrients (phosphorus, nitrogen) | — |
| Otisco Lake | Onondaga | NR | Oxygen depletion (low DO) | — |
| Cuba Lake | Allegany | NR | Nutrients (phosphorus, nitrogen), Oxygen depletion (low DO) | — |
| Oquaga Lake | Broome | NR | Nutrients (phosphorus, nitrogen) | — |
| Ballston Lake | Saratoga | NR | Nutrients (phosphorus, nitrogen) | — |
| Forest Lake | Rensselaer | NR | Mercury | ✓ |
| Deer Lake | Broome | NR | Nutrients (phosphorus, nitrogen) | — |
| Robinson Pond | Columbia | NR | Nutrients (phosphorus, nitrogen) | — |
| Long Pond | Suffolk | NR | Pathogens (E. coli, fecal) | ✓ |
| Chenango Lake | Chenango | NR | Oxygen depletion (low DO) | — |
| Smith Pond | Steuben | NR | Nutrients (phosphorus, nitrogen) | — |
| Crooked Lake | Onondaga | NR | Oxygen depletion (low DO) | — |
| Upper Little York Lake | Cortland | NR | Oxygen depletion (low DO) | — |
| Big Fresh Pond | Suffolk | NR | Nutrients (phosphorus, nitrogen) | — |
| Oscaleta Lake | Westchester | NR | Nutrients (phosphorus, nitrogen) | — |
| Barrett Pond | Putnam | NR | Mercury, Nutrients (phosphorus, nitrogen) | ✓ |
| Lake Salubria | Steuben | NR | Nutrients (phosphorus, nitrogen) | ✓ |
| Lake Mohegan | Westchester | NR | Nutrients (phosphorus, nitrogen) | — |
| Silver Lake | Wyoming | NR | Nutrients (phosphorus, nitrogen) | ✓ |
| Kirk Lake | Putnam | NR | Nutrients (phosphorus, nitrogen) | — |
| Howlands Lake | Westchester | NR | Nutrients (phosphorus, nitrogen) | — |
| Lincoln Pond | Essex | NR | Mercury | ✓ |
| Guilford Lake | Chenango | NR | Nutrients (phosphorus, nitrogen) | — |
| Lake Rippowam | Westchester | NR | Nutrients (phosphorus, nitrogen) | — |
| Canada Lake | Fulton | NR | Mercury | ✓ |
| Little Fresh Pond | Suffolk | NR | Nutrients (phosphorus, nitrogen) | — |
| Otter Lake | Oneida | NR | pH / acidity | — |
| Deer River Flow Lake | Franklin | NR | pH / acidity | — |
| Lamoka Lake | Schuyler | NR | Oxygen depletion (low DO) | — |
| Lake Peekskill | Putnam | NR | Nutrients (phosphorus, nitrogen) | — |
| Roaring Brook Lake | Putnam | NR | Metals (other than mercury) | — |
| Lake Tibet | Putnam | NR | Mercury, Nutrients (phosphorus, nitrogen) | ✓ |
| Little Long Pond | Suffolk | NR | Pathogens (E. coli, fecal) | ✓ |
| Lake Waccabuc | Westchester | NR | Ammonia, Nutrients (phosphorus, nitrogen) | — |
| Lake Moraine | Madison | NR | Nutrients (phosphorus, nitrogen), Oxygen depletion (low DO) | — |
| Burden Lake | Rensselaer | NR | Oxygen depletion (low DO) | — |
| Fulton Chain Lakes | Herkimer | NR | Pesticides | — |
| Barger Pond | Putnam | NR | Nutrients (phosphorus, nitrogen), Oxygen depletion (low DO) | — |
| Pleasant Lake | Oswego | NR | Nutrients (phosphorus, nitrogen) | — |
| China Pond | Putnam | NR | Mercury, Nutrients (phosphorus, nitrogen) | ✓ |
| Waneta Lake | Schuyler | NR | Nutrients (phosphorus, nitrogen), Oxygen depletion (low DO) | — |
| Song Lake | Cortland | NR | Oxygen depletion (low DO) | — |
| Kinderhook Lake | Columbia | NR | Nutrients (phosphorus, nitrogen), PCBs | ✓ |
| Indian Lake | Putnam | NR | Nutrients (phosphorus, nitrogen) | — |
| Eaton Reservoir | Madison | NR | Oxygen depletion (low DO) | — |
| Peach Lake | Putnam | NR | Nutrients (phosphorus, nitrogen), Pathogens (E. coli, fecal) | ✓ |
| Sleepy Hollow Lake | Greene | NR | Nutrients (phosphorus, nitrogen) | — |
| Canadice Lake | Ontario | NR | PCBs | — |
| Owasco Lake | Cayuga | NR | Pathogens (E. coli, fecal) | — |
| Lake Lacoma | Monroe | NR | Nutrients (phosphorus, nitrogen) | — |
| Montgomery Lake | Sullivan | NR | Nutrients (phosphorus, nitrogen) | — |
| Plymouth Reservoir | Chenango | NR | Nutrients (phosphorus, nitrogen) | — |
| Seven Hills Lake | Putnam | NR | Mercury, Nutrients (phosphorus, nitrogen) | ✓ |
| Saratoga Lake | Saratoga | NR | Nutrients (phosphorus, nitrogen) | — |
| Lake Carmel | Putnam | NR | Nutrients (phosphorus, nitrogen) | ✓ |
| Java Lake | Wyoming | NR | Nutrients (phosphorus, nitrogen) | ✓ |
| Duane Lake | Schenectady | NR | Nutrients (phosphorus, nitrogen) | — |
| Lake Lucille | Rockland | NR | Nutrients (phosphorus, nitrogen) | — |
| Stissing Pond | Dutchess | NR | Nutrients (phosphorus, nitrogen) | — |
| Tully Lake | Cortland | NR | Oxygen depletion (low DO) | — |
| Cazenovia Lake | Madison | NR | Nutrients (phosphorus, nitrogen) | — |
| Findley Lake | Chautauqua | NR | Nutrients (phosphorus, nitrogen), Oxygen depletion (low DO) | ✓ |
| Augur Lake | Essex | NR | Nutrients (phosphorus, nitrogen) | — |
| Sailingclub Lake | Chautauqua | NR | Nutrients (phosphorus, nitrogen) | ✓ |
| Dutchhollow Lake | Chautauqua | NR | Nuisance exotic species, Nutrients (phosphorus, nitrogen) | ✓ |
| Svp Lake | Chautauqua | NR | Nuisance exotic species, Nutrients (phosphorus, nitrogen) | ✓ |
| Northdeep Lake | Chautauqua | NR | Nutrients (phosphorus, nitrogen) | ✓ |
| Greenwood Lake | Orange | NR | Nutrients (phosphorus, nitrogen) | ✓ |
| Lake Ontario | Monroe | NR | Nutrients (phosphorus, nitrogen) | — |
| Oakland Lake | Queens | NR | Oxygen depletion (low DO), Pathogens (E. coli, fecal) | — |
Frequently Asked Questions
How many lakes are impaired in New York?
97 of 180 graded New York lakes (54%) are listed as impaired in the most recent EPA ATTAINS reporting cycle. Of those, 70 are on the federal Clean Water Act §303(d) list and 35 have an approved Total Maximum Daily Load (TMDL) restoration plan.
What does Clean Water Act §303(d) mean?
Section 303(d) of the federal Clean Water Act requires every state to identify waters that don't meet water quality standards even after pollution control measures. Each listed water must then have a Total Maximum Daily Load (TMDL) developed — a plan that caps how much of each pollutant can enter the waterbody. The "303(d) list" is the impaired-waters list. The EPA reviews each state's list every two years.
What are the top causes of impairment in New York?
The most common causes flagged across New York's impaired lakes are: Nutrients (phosphorus, nitrogen) (62 lakes); Oxygen depletion (low DO) (18 lakes); Mercury (11 lakes); pH / acidity (11 lakes); Pathogens (E. coli, fecal) (5 lakes); PCBs (4 lakes). Mercury is widespread in fish tissue across the upper Midwest from atmospheric deposition. Nutrient impairment (phosphorus, nitrogen) typically reflects agricultural runoff and urban stormwater.
Can I swim in an impaired lake?
It depends on the cause of impairment. A lake impaired for "mercury in fish tissue" is generally safe to swim in — the warning is about long-term consumption of fish. A lake impaired for "pathogens" (E. coli) or "algal growth" may pose a swimming risk and often has a separate beach advisory. Check the cause categories listed for each lake below, and consult your state health department's beach monitoring program for current advisories.
Where does this impairment data come from?
Every impairment record on this page comes from the EPA's ATTAINS (Assessment and TMDL Tracking and Implementation System) public dataset, the federal repository of state-reported water quality assessments. EPA ATTAINS is published as GeoParquet files on the EPA Office of Water S3 bucket and refreshed several times per year. Causes and use-support codes follow EPA's standard taxonomy.
More on impaired waters
What it means when a lake is listed as impaired, why mercury is the most common reason, and why a listed lake can still be clear water with a good grade.
Why states issue fish-consumption advisories, which contaminants — mercury, PCBs, PFAS — drive them, and how to eat the fish you catch more safely.
How phosphorus and nutrient runoff drive algae growth and turn lakes green, where the nutrients come from, and what it means for a lake's grade.
Which lakes are actually improving: multi-year EPA monitoring trends, the named recoveries still in progress, and what it takes to move a letter grade.
Data source
Impairment data from the EPA ATTAINS (Assessment and TMDL Tracking and Implementation System) public dataset. Assessment unit IDs are matched to LakeQuality lakes by name and proximity; some lakes may not appear here if their ATTAINS name doesn't match our naming convention. For an official query, consult New York's state water-quality agency.