What was found in Thompson's water
The level at the city's main supplier, the highest level anywhere in the city, the EPA limit for each, and where every figure comes from.
| Contaminant | Level vs EPA limit | Suppliers | Source |
|---|---|---|---|
| Nitrate | 150 µg/L 1.5% of the EPA limit 10000 µg/L Main supplier: EMERALD GREEN LAKE LOUISE MARIE WC · 2,400 people · 2019
Highest in the city: 3430 µg/L — TCFD - HARRIS · 600 people · 2019 | 14/19 | SYR4 |
| Nitrate-Nitrite | 947.95 µg/L 9.5% of the EPA limit 10000 µg/L Highest in the city: TCFD - HARRIS · 600 people · 2013 | 2/19 | SYR4 |
| Barium | 43.2 µg/L 2.2% of the EPA limit 2000 µg/L Main supplier: EMERALD GREEN LAKE LOUISE MARIE WC · 2,400 people · 2019
Highest in the city: 821.35 µg/L — TCFD - HARRIS · 600 people · 2019 | 13/19 | SYR4 |
| Copper | 616 µg/L 47% of the EPA limit 1300 µg/L Highest in the city: TCFD - HARRIS · 600 people · 2017 | 4/19 | SYR4 |
| Fluoride | 510 µg/L 13% of the EPA limit 4000 µg/L Highest in the city: MELODY LAKE WD · 150 people · 2018 | 3/19 | SYR4 |
| TTHM | 73.4 µg/L 92% of the EPA limit 80 µg/L Main supplier: EMERALD GREEN LAKE LOUISE MARIE WC · 2,400 people · 2019
Highest in the city: 79.5 µg/L — ADELAAR WD · 1,000 people · 2019 | 9/19 | SYR4 |
| Chloroform | 52.9 µg/L No EPA limit set Main supplier: EMERALD GREEN LAKE LOUISE MARIE WC · 2,400 people · 2019
Highest in the city: 64 µg/L — ADELAAR WD · 1,000 people · 2019 | 9/19 | SYR4 |
| Total Haloacetic Acids (HAA5) | 35.9 µg/L 60% of the EPA limit 60 µg/L Main supplier: EMERALD GREEN LAKE LOUISE MARIE WC · 2,400 people · 2019
Highest in the city: 39.9 µg/L — KIAMESHA ARTESIAN SPRING WATER COMPANY · 879 people · 2019 | 8/19 | SYR4 |
| Cyanide | 34.2 µg/L 17% of the EPA limit 200 µg/L Highest in the city: DILLON FARM WD · 30 people · 2018 | 1/19 | SYR4 |
| Dichloroacetic Acid | 18 µg/L No EPA limit set Main supplier: EMERALD GREEN LAKE LOUISE MARIE WC · 2,400 people · 2019
Highest in the city: 25.5 µg/L — ADELAAR WD · 1,000 people · 2019 | 8/19 | SYR4 |
| Nitrite | 21 µg/L 2.1% of the EPA limit 1000 µg/L Highest in the city: TCFD - HARRIS · 600 people · 2013 | 1/19 | SYR4 |
| Trichloroacetic Acid | 16.89 µg/L No EPA limit set Main supplier: EMERALD GREEN LAKE LOUISE MARIE WC · 2,400 people · 2019
Highest in the city: 18.12 µg/L — KIAMESHA ARTESIAN SPRING WATER COMPANY · 879 people · 2019 | 7/19 | SYR4 |
| Bromodichloromethane | 16.7 µg/L No EPA limit set Main supplier: EMERALD GREEN LAKE LOUISE MARIE WC · 2,400 people · 2019 | 9/19 | SYR4 |
| Combined Uranium | 13.0489 µg/L 43% of the EPA limit 30 µg/L Highest in the city: FOREST PARK ESTATES · 300 people · 2019 | 12/19 | SYR4 |
| Dibromochloromethane | 4.36 µg/L No EPA limit set Main supplier: EMERALD GREEN LAKE LOUISE MARIE WC · 2,400 people · 2019
Highest in the city: 10.85 µg/L — SACKETT LAKE ESTATES · 80 people · 2019 | 9/19 | SYR4 |
| Combined Radium (-226 And -228) | 9.516 pCi/L 190% of the EPA limit, at the 95th percentile of samples — 5 pCi/L Highest in the city: FOREST PARK ESTATES · 300 people · 2016 | 12/19 | SYR4 |
| Arsenic | 0.6900 µg/L 6.9% of the EPA limit 10 µg/L Main supplier: EMERALD GREEN LAKE LOUISE MARIE WC · 2,400 people · 2019
Highest in the city: 9.19 µg/L — COLD SPRING RD WD - THOMPSON · 82 people · 2018 | 9/19 | SYR4 |
| Lead | 8.7 µg/L 58% of the EPA limit 15 µg/L Highest in the city: LUCKY LAKE WD · 60 people · 2016 | 4/19 | SYR4 |
| Bromoform | 6.86 µg/L No EPA limit set Highest in the city: SACKETT LAKE ESTATES · 80 people · 2019 | 5/19 | SYR4 |
| Gross Alpha, Excl. Radon And U | 5.99 pCi/L 40% of the EPA limit 15 pCi/L Highest in the city: FOREST PARK ESTATES · 300 people · 2019 | 10/19 | SYR4 |
| Gross Beta Particle Activity | 1.5 pCi/L No EPA limit set Main supplier: EMERALD GREEN LAKE LOUISE MARIE WC · 2,400 people · 2019
Highest in the city: 5.9 pCi/L — SACKETT LAKE ESTATES · 80 people · 2017 | 8/19 | SYR4 |
| Dibromoacetic Acid | 1.9275 µg/L No EPA limit set Main supplier: EMERALD GREEN LAKE LOUISE MARIE WC · 2,400 people · 2019
Highest in the city: 4.53 µg/L — SACKETT LAKE ESTATES · 80 people · 2019 | 7/19 | SYR4 |
| Toluene | 4 µg/L 0.4% of the EPA limit 1000 µg/L Highest in the city: TCFD - HARRIS · 600 people · 2019 | 1/19 | SYR4 |
| Monochloroacetic Acid | 3.34 µg/L No EPA limit set Main supplier: EMERALD GREEN LAKE LOUISE MARIE WC · 2,400 people · 2019 | 3/19 | SYR4 |
| Cadmium | 2.325 µg/L 47% of the EPA limit 5 µg/L Highest in the city: TCFD - HARRIS · 600 people · 2019 | 1/19 | SYR4 |
| Selenium | 2.3 µg/L 4.6% of the EPA limit 50 µg/L Highest in the city: KINNEBROOK ESTATES MHP · 680 people · 2018 | 2/19 | SYR4 |
| Chromium | 1.9 µg/L 1.9% of the EPA limit 100 µg/L Highest in the city: KIAMESHA ARTESIAN SPRING WATER COMPANY · 879 people · 2019 | 1/19 | SYR4 |
| Monobromoacetic Acid | 0.5600 µg/L No EPA limit set Main supplier: EMERALD GREEN LAKE LOUISE MARIE WC · 2,400 people · 2019
Highest in the city: 1 µg/L — KINNEBROOK ESTATES MHP · 680 people · 2019 | 3/19 | SYR4 |
| Thallium, Total | 1 µg/L 50% of the EPA limit 2 µg/L Highest in the city: DILLON FARM WD · 30 people · 2018 | 2/19 | SYR4 |
| Tetrachloroethylene | 0.6200 µg/L 12% of the EPA limit 5 µg/L Highest in the city: KIAMESHA ARTESIAN SPRING WATER COMPANY · 879 people · 2019 | 1/19 | SYR4 |
| Lead | 0.0027 mg/L 18% of the EPA limit 0.0150 mg/L Main supplier: EMERALD GREEN LAKE LOUISE MARIE WC · 2,400 people · 2023
Highest in the city: 0.0200 mg/L — LUCKY LAKE WD · 60 people · 2025 | 18/19 | LCR |
Each bar shows the measured level as a share of the EPA limit: green is
well under, amber is close to it, red is over. For lead and copper the
limit applies to exactly the 90th-percentile figure shown, so red there
means a real exceedance. For everything else the limit applies to a
running annual average while the figure is the 95th percentile of the
system's samples — over 100% is worth reading, but is not by itself a
violation.
Formal violations are listed separately.
These are the utilities' own EPA-reported results, not a city-wide
average. A detection means the lab measured the
substance — it isn't the same as exceeding a legal limit. Hover a source
tag to see the EPA program and years behind each figure.
Water suppliers serving Thompson
| Supplier | Population served |
|---|---|
| EMERALD GREEN LAKE LOUISE MARIE WC | 2,400 |
| ADELAAR WD | 1,000 |
| KIAMESHA ARTESIAN SPRING WATER COMPANY | 879 |
| KINNEBROOK ESTATES MHP | 680 |
| PARKSIDE ESTATES | 600 |
| TCFD - HARRIS | 600 |
| HARRIS WOODS HOA | 440 |
| WINDSOR HILL ESTATES | 384 |
| KIAMESHA-ROUTE 42 WD | 331 |
| FOREST PARK ESTATES | 300 |
| CHARM ESTATES | 280 |
| GREENTREE WATER COMPANY | 184 |
| MELODY LAKE WD | 150 |
| CRYSTAL WATER SUPPLY COMPANY | 146 |
| COLD SPRING RD WD - THOMPSON | 82 |
| SACKETT LAKE ESTATES | 80 |
| LUCKY LAKE WD | 60 |
| BROOKSIDE MOBILE HOME PARK | 36 |
| DILLON FARM WD | 30 |
Frequently asked questions about Thompson tap water
Is Thompson tap water safe to drink?
EPA testing detected 31 contaminants in the water serving Thompson. A detection isn't the same as a violation — most detected levels are within federal limits. Check the level and source for each contaminant above, and your utility's annual Consumer Confidence Report for the official compliance status.
How many water suppliers serve Thompson?
19 public water suppliers report drinking-water monitoring for Thompson, New York to the EPA. Each is listed above with its population served.
What contaminants are in Thompson's water?
The contaminants EPA monitoring detected in Thompson include Nitrate, Nitrate-Nitrite, Barium, Copper, Fluoride. The full list, with the level at the main supplier and the data source, is in the table above.
Where does this data come from?
Every figure is official EPA drinking-water monitoring — the Lead & Copper Rule, the UCMR-5 nationwide testing program, and the EPA Six-Year Review — not our own testing. Each number is labelled with its source and period.