What was found in Carlisle'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 | 4784.999999999999 µg/L 48% of the EPA limit 10000 µg/L Main supplier: CARLISLE WATER TRMT PLT · 26,000 people · 2019
Highest in the city: 8939.999999999998 µg/L — MIDDLESEX TWP MUNI AUTH · 3,527 people · 2019 | 6/7 | SYR4 |
| Fluoride | 586 µg/L 15% of the EPA limit 4000 µg/L Main supplier: CARLISLE WATER TRMT PLT · 26,000 people · 2019
Highest in the city: 1026 µg/L — US ARMY GARRISON · 1,700 people · 2018 | 6/7 | SYR4 |
| Copper | 103 µg/L 7.9% of the EPA limit 1300 µg/L Main supplier: CARLISLE WATER TRMT PLT · 26,000 people · 2019
Highest in the city: 480.9999999999985 µg/L — US ARMY GARRISON · 1,700 people · 2019 | 6/7 | SYR4 |
| Lead | 21.999999999999996 µg/L 147% of the EPA limit, at the 95th percentile of samples — 15 µg/L Main supplier: CARLISLE WATER TRMT PLT · 26,000 people · 2019
Highest in the city: 248.9999999999999 µg/L — MIDDLESEX TWP MUNI AUTH · 3,527 people · 2019 | 6/7 | SYR4 |
| TTHM | 72.06499999999997 µg/L 90% of the EPA limit 80 µg/L Main supplier: CARLISLE WATER TRMT PLT · 26,000 people · 2019
Highest in the city: 83.92999999999999 µg/L — N MIDDLETON WATER AUTH · 8,455 people · 2019 | 7/7 | SYR4 |
| Barium | 40.3 µg/L 2% of the EPA limit 2000 µg/L Main supplier: CARLISLE WATER TRMT PLT · 26,000 people · 2019
Highest in the city: 81.9 µg/L — ROLLING HILLS ESTATES · 175 people · 2018 | 6/7 | SYR4 |
| Chloroform | 57.45999999999999 µg/L No EPA limit set Main supplier: CARLISLE WATER TRMT PLT · 26,000 people · 2019
Highest in the city: 63.58999999999999 µg/L — N MIDDLETON WATER AUTH · 8,455 people · 2019 | 7/7 | SYR4 |
| Total Haloacetic Acids (HAA5) | 56.31999999999998 µg/L 94% of the EPA limit 60 µg/L Main supplier: CARLISLE WATER TRMT PLT · 26,000 people · 2019
Highest in the city: 60.35 µg/L — N MIDDLETON WATER AUTH · 8,455 people · 2019 | 7/7 | SYR4 |
| Dichloroacetic Acid | 21.93 µg/L No EPA limit set Main supplier: CARLISLE WATER TRMT PLT · 26,000 people · 2019 | 6/7 | SYR4 |
| Trichloroacetic Acid | 18.69 µg/L No EPA limit set Main supplier: CARLISLE WATER TRMT PLT · 26,000 people · 2019 | 4/7 | SYR4 |
| Bromodichloromethane | 13.999999999999982 µg/L No EPA limit set Main supplier: CARLISLE WATER TRMT PLT · 26,000 people · 2019
Highest in the city: 15.379999999999995 µg/L — N MIDDLETON WATER AUTH · 8,455 people · 2019 | 7/7 | SYR4 |
| Cyanide | 2.6 µg/L 1.3% of the EPA limit 200 µg/L Main supplier: CARLISLE WATER TRMT PLT · 26,000 people · 2019
Highest in the city: 6 µg/L — N MIDDLETON WATER AUTH · 8,455 people · 2018 | 3/7 | SYR4 |
| Selenium | 5.9 µg/L 12% of the EPA limit 50 µg/L Highest in the city: CREEK VIEW MOBILE HOME COMMUN · 80 people · 2018 | 1/7 | SYR4 |
| Dibromochloromethane | 4.394999999999996 µg/L No EPA limit set Main supplier: CARLISLE WATER TRMT PLT · 26,000 people · 2019
Highest in the city: 4.425000000000001 µg/L — N MIDDLETON WATER AUTH · 8,455 people · 2019 | 7/7 | SYR4 |
| Chromium | 3.45 µg/L 3.5% of the EPA limit 100 µg/L Highest in the city: MIDDLESEX TWP MUNI AUTH · 3,527 people · 2018 | 4/7 | SYR4 |
| Monobromoacetic Acid | 2.83 µg/L No EPA limit set Main supplier: CARLISLE WATER TRMT PLT · 26,000 people · 2019 | 1/7 | SYR4 |
| Monochloroacetic Acid | 2.7 µg/L No EPA limit set Main supplier: CARLISLE WATER TRMT PLT · 26,000 people · 2019 | 1/7 | SYR4 |
| Tetrachloroethylene | 1.5299999999999998 µg/L 31% of the EPA limit 5 µg/L Highest in the city: US ARMY GARRISON · 1,700 people · 2019 | 1/7 | SYR4 |
| Dibromoacetic Acid | 1.4549999999999998 µg/L No EPA limit set Main supplier: CARLISLE WATER TRMT PLT · 26,000 people · 2019 | 1/7 | SYR4 |
| Bromoform | 0.9810 µg/L No EPA limit set Highest in the city: US ARMY GARRISON · 1,700 people · 2019 | 2/7 | SYR4 |
| Trichloroethylene | 0.5195 µg/L 10% of the EPA limit 5 µg/L Highest in the city: US ARMY GARRISON · 1,700 people · 2019 | 1/7 | SYR4 |
| Atrazine | 0.2800 µg/L 9.3% of the EPA limit 3 µg/L Main supplier: CARLISLE WATER TRMT PLT · 26,000 people · 2018
Highest in the city: 0.4200 µg/L — N MIDDLETON WATER AUTH · 8,455 people · 2018 | 2/7 | SYR4 |
| Cadmium | 0.4000 µg/L 8% of the EPA limit 5 µg/L Highest in the city: N MIDDLETON WATER AUTH · 8,455 people · 2018 | 1/7 | SYR4 |
| Lead | 0.0026 mg/L 17% of the EPA limit 0.0150 mg/L Main supplier: CARLISLE WATER TRMT PLT · 26,000 people · 2025
Highest in the city: 0.0608 mg/L — US ARMY GARRISON · 1,700 people · 2016 | 6/7 | LCR |
| PFOS | 0.0113 µg/L No EPA limit set Main supplier: CARLISLE WATER TRMT PLT · 26,000 people · 2023
Highest in the city: 0.0169 µg/L — N MIDDLETON WATER AUTH · 8,455 people · 2025 | 2/7 | UCMR-5 |
| PFOA | 0.0050 µg/L No EPA limit set Main supplier: CARLISLE WATER TRMT PLT · 26,000 people · 2023
Highest in the city: 0.0080 µg/L — N MIDDLETON WATER AUTH · 8,455 people · 2025 | 2/7 | UCMR-5 |
| PFBS | 0.0072 µg/L No EPA limit set Main supplier: CARLISLE WATER TRMT PLT · 26,000 people · 2023
Highest in the city: 0.0078 µg/L — N MIDDLETON WATER AUTH · 8,455 people · 2025 | 2/7 | UCMR-5 |
| Pfhxa | 0.0051 µg/L No EPA limit set Main supplier: CARLISLE WATER TRMT PLT · 26,000 people · 2023
Highest in the city: 0.0055 µg/L — N MIDDLETON WATER AUTH · 8,455 people · 2025 | 2/7 | UCMR-5 |
| Pfba | 0.0052 µg/L No EPA limit set Main supplier: CARLISLE WATER TRMT PLT · 26,000 people · 2023 | 1/7 | UCMR-5 |
| Pfpea | 0.0039 µg/L No EPA limit set Main supplier: CARLISLE WATER TRMT PLT · 26,000 people · 2023 | 2/7 | UCMR-5 |
| PFHXS | 0.0035 µg/L No EPA limit set Highest in the city: N MIDDLETON WATER AUTH · 8,455 people · 2025 | 1/7 | 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 Carlisle
| Supplier | Population served |
|---|---|
| CARLISLE WATER TRMT PLT | 26,000 |
| N MIDDLETON WATER AUTH | 8,455 |
| MIDDLESEX TWP MUNI AUTH | 3,527 |
| US ARMY GARRISON | 1,700 |
| ROLLING HILLS ESTATES | 175 |
| SOUTHAMPTON MANOR MHP | 160 |
| CREEK VIEW MOBILE HOME COMMUN | 80 |
Frequently asked questions about Carlisle tap water
Is Carlisle tap water safe to drink?
EPA testing detected 31 contaminants in the water serving Carlisle. 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 Carlisle?
7 public water suppliers report drinking-water monitoring for Carlisle, Pennsylvania to the EPA. Each is listed above with its population served.
What contaminants are in Carlisle's water?
The contaminants EPA monitoring detected in Carlisle include Nitrate, Fluoride, Copper, Lead, TTHM. 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.