What was found in Oakland'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 | 536 µg/L 5.4% of the EPA limit 10000 µg/L Main supplier: TOWN OF MOUNTAIN LAKE PARK · 3,000 people · 2019
Highest in the city: 910 µg/L — TOWN OF OAKLAND · 1,850 people · 2019 | 5/7 | SYR4 |
| Nitrate-Nitrite | 901 µg/L 9% of the EPA limit 10000 µg/L Highest in the city: TOWN OF OAKLAND · 1,850 people · 2018 | 3/7 | SYR4 |
| Fluoride | 340 µg/L 8.5% of the EPA limit 4000 µg/L Main supplier: TOWN OF MOUNTAIN LAKE PARK · 3,000 people · 2017
Highest in the city: 488.5 µg/L — TOWN OF OAKLAND · 1,850 people · 2019 | 5/7 | SYR4 |
| TTHM | 16.376 µg/L 20% of the EPA limit 80 µg/L Main supplier: TOWN OF MOUNTAIN LAKE PARK · 3,000 people · 2019
Highest in the city: 183.028 µg/L — TOWN OF OAKLAND · 1,850 people · 2019 | 7/7 | SYR4 |
| Chloroform | 9.305 µg/L No EPA limit set Main supplier: TOWN OF MOUNTAIN LAKE PARK · 3,000 people · 2015
Highest in the city: 171.347 µg/L — TOWN OF OAKLAND · 1,850 people · 2019 | 6/7 | SYR4 |
| Total Haloacetic Acids (HAA5) | 12.52 µg/L 21% of the EPA limit 60 µg/L Main supplier: TOWN OF MOUNTAIN LAKE PARK · 3,000 people · 2019
Highest in the city: 125.438 µg/L — TOWN OF OAKLAND · 1,850 people · 2019 | 6/7 | SYR4 |
| Dichloroacetic Acid | 5.211 µg/L No EPA limit set Main supplier: TOWN OF MOUNTAIN LAKE PARK · 3,000 people · 2015
Highest in the city: 68.056 µg/L — TOWN OF OAKLAND · 1,850 people · 2015 | 6/7 | SYR4 |
| Barium | 66.655 µg/L 3.3% of the EPA limit 2000 µg/L Main supplier: TOWN OF MOUNTAIN LAKE PARK · 3,000 people · 2017 | 7/7 | SYR4 |
| Trichloroacetic Acid | 3.3465 µg/L No EPA limit set Main supplier: TOWN OF MOUNTAIN LAKE PARK · 3,000 people · 2015
Highest in the city: 64.933 µg/L — TOWN OF OAKLAND · 1,850 people · 2015 | 5/7 | SYR4 |
| Dibromoacetic Acid | 20.5 µg/L No EPA limit set Highest in the city: TOWN OF OAKLAND · 1,850 people · 2015 | 1/7 | SYR4 |
| Selenium | 19.8 µg/L 40% of the EPA limit 50 µg/L Main supplier: TOWN OF MOUNTAIN LAKE PARK · 3,000 people · 2017 | 3/7 | SYR4 |
| Bromodichloromethane | 3.73 µg/L No EPA limit set Main supplier: TOWN OF MOUNTAIN LAKE PARK · 3,000 people · 2015
Highest in the city: 10.338 µg/L — TOWN OF FRIENDSVILLE · 622 people · 2019 | 6/7 | SYR4 |
| Monochloroacetic Acid | 7.63 µg/L No EPA limit set Highest in the city: TOWN OF OAKLAND · 1,850 people · 2015 | 2/7 | SYR4 |
| Arsenic | 6.4285 µg/L 64% of the EPA limit 10 µg/L Main supplier: TOWN OF MOUNTAIN LAKE PARK · 3,000 people · 2017 | 4/7 | SYR4 |
| Toluene | 2.83 µg/L 0.3% of the EPA limit 1000 µg/L Highest in the city: TOWN OF OAKLAND · 1,850 people · 2019 | 1/7 | SYR4 |
| Dichloromethane | 2.5 µg/L 50% of the EPA limit 5 µg/L Highest in the city: TOWN OF FRIENDSVILLE · 622 people · 2019 | 1/7 | SYR4 |
| Gross Alpha, Excl. Radon And U | 2 pCi/L 13% of the EPA limit 15 pCi/L Highest in the city: TOWN OF DEER PARK · 272 people · 2017 | 2/7 | SYR4 |
| Mercury | 1.9 µg/L 95% of the EPA limit 2 µg/L Highest in the city: TOWN OF OAKLAND · 1,850 people · 2019 | 1/7 | SYR4 |
| Dibromochloromethane | 1.8765 µg/L No EPA limit set Main supplier: TOWN OF MOUNTAIN LAKE PARK · 3,000 people · 2015 | 5/7 | SYR4 |
| Chromium | 1.05 µg/L 1.1% of the EPA limit 100 µg/L Highest in the city: BLOOMINGTON · 350 people · 2019 | 2/7 | SYR4 |
| Combined Radium (-226 And -228) | 1 pCi/L 20% of the EPA limit 5 pCi/L Highest in the city: TOWN OF FRIENDSVILLE · 622 people · 2019 | 1/7 | SYR4 |
| Dalapon | 0.9600 µg/L 0.5% of the EPA limit 200 µg/L Highest in the city: TOWN OF OAKLAND · 1,850 people · 2018 | 1/7 | SYR4 |
| Bromoform | 0.5600 µg/L No EPA limit set Main supplier: TOWN OF MOUNTAIN LAKE PARK · 3,000 people · 2015 | 1/7 | SYR4 |
| Simazine | 0.5500 µg/L 14% of the EPA limit 4 µg/L Highest in the city: TOWN OF FRIENDSVILLE · 622 people · 2018 | 1/7 | SYR4 |
| Lead | 0.0016 mg/L 11% of the EPA limit 0.0150 mg/L Main supplier: TOWN OF MOUNTAIN LAKE PARK · 3,000 people · 2023
Highest in the city: 0.0085 mg/L — BLOOMINGTON · 350 people · 2017 | 7/7 | 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 Oakland
| Supplier | Population served |
|---|---|
| TOWN OF MOUNTAIN LAKE PARK | 3,000 |
| TOWN OF OAKLAND | 1,850 |
| TOWN OF FRIENDSVILLE | 622 |
| BLOOMINGTON | 350 |
| TOWN OF DEER PARK | 272 |
| CRELLIN | 230 |
| GORMAN | 150 |
Frequently asked questions about Oakland tap water
Is Oakland tap water safe to drink?
EPA testing detected 25 contaminants in the water serving Oakland. 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 Oakland?
7 public water suppliers report drinking-water monitoring for Oakland, Maryland to the EPA. Each is listed above with its population served.
What contaminants are in Oakland's water?
The contaminants EPA monitoring detected in Oakland include Nitrate, Nitrate-Nitrite, Fluoride, TTHM, Chloroform. 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.