What was found in Poolesville'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-Nitrite | 6800 µg/L 68% of the EPA limit 10000 µg/L Main supplier: TOWN OF POOLESVILLE · 6,005 people · 2017 | 1/1 | SYR4 |
| Nitrate | 6500 µg/L 65% of the EPA limit 10000 µg/L Main supplier: TOWN OF POOLESVILLE · 6,005 people · 2019 | 1/1 | SYR4 |
| Barium | 1042 µg/L 52% of the EPA limit 2000 µg/L Main supplier: TOWN OF POOLESVILLE · 6,005 people · 2019 | 1/1 | SYR4 |
| Fluoride | 200 µg/L 5% of the EPA limit 4000 µg/L Main supplier: TOWN OF POOLESVILLE · 6,005 people · 2018 | 1/1 | SYR4 |
| Lithium | 41.1 µg/L No EPA limit set Main supplier: TOWN OF POOLESVILLE · 6,005 people · 2025 | 1/1 | UCMR-5 |
| TTHM | 23.322 µg/L 29% of the EPA limit 80 µg/L Main supplier: TOWN OF POOLESVILLE · 6,005 people · 2019 | 1/1 | SYR4 |
| Combined Uranium | 21.8051 µg/L 73% of the EPA limit 30 µg/L Main supplier: TOWN OF POOLESVILLE · 6,005 people · 2019 | 1/1 | SYR4 |
| Gross Alpha, Excl. Radon And U | 17.08 pCi/L 114% of the EPA limit, at the 95th percentile of samples — 15 pCi/L Main supplier: TOWN OF POOLESVILLE · 6,005 people · 2019 | 1/1 | SYR4 |
| Chloroform | 10.24 µg/L No EPA limit set Main supplier: TOWN OF POOLESVILLE · 6,005 people · 2019 | 1/1 | SYR4 |
| Total Haloacetic Acids (HAA5) | 9.5995 µg/L 16% of the EPA limit 60 µg/L Main supplier: TOWN OF POOLESVILLE · 6,005 people · 2019 | 1/1 | SYR4 |
| Gross Beta Particle Activity | 6.75 pCi/L No EPA limit set Main supplier: TOWN OF POOLESVILLE · 6,005 people · 2019 | 1/1 | SYR4 |
| Bromodichloromethane | 5.656 µg/L No EPA limit set Main supplier: TOWN OF POOLESVILLE · 6,005 people · 2019 | 1/1 | SYR4 |
| Dichloroacetic Acid | 5.0325 µg/L No EPA limit set Main supplier: TOWN OF POOLESVILLE · 6,005 people · 2015 | 1/1 | SYR4 |
| Dibromochloromethane | 4.0075 µg/L No EPA limit set Main supplier: TOWN OF POOLESVILLE · 6,005 people · 2019 | 1/1 | SYR4 |
| Trichloroacetic Acid | 3.847 µg/L No EPA limit set Main supplier: TOWN OF POOLESVILLE · 6,005 people · 2015 | 1/1 | SYR4 |
| Monochloroacetic Acid | 3.51 µg/L No EPA limit set Main supplier: TOWN OF POOLESVILLE · 6,005 people · 2015 | 1/1 | SYR4 |
| Combined Radium (-226 And -228) | 2.36 pCi/L 47% of the EPA limit 5 pCi/L Main supplier: TOWN OF POOLESVILLE · 6,005 people · 2019 | 1/1 | SYR4 |
| Arsenic | 2.295 µg/L 23% of the EPA limit 10 µg/L Main supplier: TOWN OF POOLESVILLE · 6,005 people · 2018 | 1/1 | SYR4 |
| Selenium | 1.836 µg/L 3.7% of the EPA limit 50 µg/L Main supplier: TOWN OF POOLESVILLE · 6,005 people · 2018 | 1/1 | SYR4 |
| Dibromoacetic Acid | 1.62105 µg/L No EPA limit set Main supplier: TOWN OF POOLESVILLE · 6,005 people · 2015 | 1/1 | SYR4 |
| Bromoform | 1.492 µg/L No EPA limit set Main supplier: TOWN OF POOLESVILLE · 6,005 people · 2019 | 1/1 | SYR4 |
| Pfpea | 0.0151 µg/L No EPA limit set Main supplier: TOWN OF POOLESVILLE · 6,005 people · 2025 | 1/1 | UCMR-5 |
| Pfhxa | 0.0098 µg/L No EPA limit set Main supplier: TOWN OF POOLESVILLE · 6,005 people · 2025 | 1/1 | UCMR-5 |
| Pfba | 0.0089 µg/L No EPA limit set Main supplier: TOWN OF POOLESVILLE · 6,005 people · 2025 | 1/1 | UCMR-5 |
| PFHXS | 0.0069 µg/L No EPA limit set Main supplier: TOWN OF POOLESVILLE · 6,005 people · 2025 | 1/1 | UCMR-5 |
| PFOS | 0.0065 µg/L No EPA limit set Main supplier: TOWN OF POOLESVILLE · 6,005 people · 2025 | 1/1 | UCMR-5 |
| Pfhpa | 0.0054 µg/L No EPA limit set Main supplier: TOWN OF POOLESVILLE · 6,005 people · 2025 | 1/1 | UCMR-5 |
| PFOA | 0.0054 µg/L No EPA limit set Main supplier: TOWN OF POOLESVILLE · 6,005 people · 2025 | 1/1 | UCMR-5 |
| Lead | 0.0050 mg/L 33% of the EPA limit 0.0150 mg/L Main supplier: TOWN OF POOLESVILLE · 6,005 people · 2018 | 1/1 | LCR |
| PFBS | 0.0048 µg/L No EPA limit set Main supplier: TOWN OF POOLESVILLE · 6,005 people · 2025 | 1/1 | UCMR-5 |
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 Poolesville
| Supplier | Population served |
|---|---|
| TOWN OF POOLESVILLE | 6,005 |
Frequently asked questions about Poolesville tap water
Is Poolesville tap water safe to drink?
EPA testing detected 30 contaminants in the water serving Poolesville. 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 Poolesville?
1 public water supplier report drinking-water monitoring for Poolesville, Maryland to the EPA. Each is listed above with its population served.
What contaminants are in Poolesville's water?
The contaminants EPA monitoring detected in Poolesville include Nitrate-Nitrite, Nitrate, Barium, Fluoride, Lithium. 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.