What was found in Cambridge'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 |
|---|---|---|---|
| Fluoride | 1146 µg/L 29% of the EPA limit 4000 µg/L Main supplier: CAMBRIDGE, CITY OF · 10,520 people · 2019 | 1/3 | SYR4 |
| Nitrate | 760 µg/L 7.6% of the EPA limit 10000 µg/L Main supplier: CAMBRIDGE, CITY OF · 10,520 people · 2019 | 1/3 | SYR4 |
| Copper | 88.7 µg/L 6.8% of the EPA limit 1300 µg/L Main supplier: CAMBRIDGE, CITY OF · 10,520 people · 2019
Highest in the city: 541.8 µg/L — GUERNSEY CO. WATER DEPT. · 8,891 people · 2017 | 3/3 | SYR4 |
| TTHM | 90.98 µg/L 114% of the EPA limit, at the 95th percentile of samples — 80 µg/L Main supplier: CAMBRIDGE, CITY OF · 10,520 people · 2019
Highest in the city: 111.5 µg/L — GUERNSEY CO. WATER DEPT. · 8,891 people · 2019 | 3/3 | SYR4 |
| Chloroform | 69.75 µg/L No EPA limit set Main supplier: CAMBRIDGE, CITY OF · 10,520 people · 2019
Highest in the city: 80.48 µg/L — GUERNSEY CO. WATER DEPT. · 8,891 people · 2019 | 3/3 | SYR4 |
| Total Haloacetic Acids (HAA5) | 54.86 µg/L 91% of the EPA limit 60 µg/L Main supplier: CAMBRIDGE, CITY OF · 10,520 people · 2019
Highest in the city: 60.52 µg/L — WESTERN GUERNSEY REGIONAL WATER DISTRICT · 3,225 people · 2019 | 3/3 | SYR4 |
| Trichloroacetic Acid | 31.89 µg/L No EPA limit set Main supplier: CAMBRIDGE, CITY OF · 10,520 people · 2019
Highest in the city: 32.46 µg/L — WESTERN GUERNSEY REGIONAL WATER DISTRICT · 3,225 people · 2019 | 3/3 | SYR4 |
| Barium | 31 µg/L 1.6% of the EPA limit 2000 µg/L Main supplier: CAMBRIDGE, CITY OF · 10,520 people · 2019 | 1/3 | SYR4 |
| Dichloroacetic Acid | 24.83 µg/L No EPA limit set Main supplier: CAMBRIDGE, CITY OF · 10,520 people · 2019
Highest in the city: 30.28 µg/L — GUERNSEY CO. WATER DEPT. · 8,891 people · 2019 | 3/3 | SYR4 |
| Bromodichloromethane | 22.8 µg/L No EPA limit set Main supplier: CAMBRIDGE, CITY OF · 10,520 people · 2019
Highest in the city: 28.435 µg/L — WESTERN GUERNSEY REGIONAL WATER DISTRICT · 3,225 people · 2019 | 3/3 | SYR4 |
| Lithium | 9.7 µg/L No EPA limit set Highest in the city: GUERNSEY CO. WATER DEPT. · 8,891 people · 2025 | 1/3 | UCMR-5 |
| Dibromochloromethane | 6.198 µg/L No EPA limit set Main supplier: CAMBRIDGE, CITY OF · 10,520 people · 2019
Highest in the city: 9.505 µg/L — WESTERN GUERNSEY REGIONAL WATER DISTRICT · 3,225 people · 2019 | 3/3 | SYR4 |
| Lead | 8.85 µg/L 59% of the EPA limit 15 µg/L Main supplier: CAMBRIDGE, CITY OF · 10,520 people · 2018 | 3/3 | SYR4 |
| Dibromoacetic Acid | 6.16 µg/L No EPA limit set Main supplier: CAMBRIDGE, CITY OF · 10,520 people · 2019 | 3/3 | SYR4 |
| Monochloroacetic Acid | 4.16 µg/L No EPA limit set Main supplier: CAMBRIDGE, CITY OF · 10,520 people · 2019
Highest in the city: 5.82 µg/L — WESTERN GUERNSEY REGIONAL WATER DISTRICT · 3,225 people · 2019 | 3/3 | SYR4 |
| Chromium | 1.28 µg/L 1.3% of the EPA limit 100 µg/L Main supplier: CAMBRIDGE, CITY OF · 10,520 people · 2019 | 1/3 | SYR4 |
| Bromoform | 0.8975 µg/L No EPA limit set Main supplier: CAMBRIDGE, CITY OF · 10,520 people · 2019
Highest in the city: 1.156 µg/L — WESTERN GUERNSEY REGIONAL WATER DISTRICT · 3,225 people · 2019 | 2/3 | SYR4 |
| PFOA | 0.0056 µg/L No EPA limit set Main supplier: CAMBRIDGE, CITY OF · 10,520 people · 2025
Highest in the city: 0.0098 µg/L — GUERNSEY CO. WATER DEPT. · 8,891 people · 2025 | 2/3 | UCMR-5 |
| Pfba | 0.0054 µg/L No EPA limit set Main supplier: CAMBRIDGE, CITY OF · 10,520 people · 2025 | 1/3 | UCMR-5 |
| Lead | 0.0 mg/L 0% of the EPA limit 0.0150 mg/L Main supplier: CAMBRIDGE, CITY OF · 10,520 people · 2025 | 3/3 | 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 Cambridge
| Supplier | Population served |
|---|---|
| CAMBRIDGE, CITY OF | 10,520 |
| GUERNSEY CO. WATER DEPT. | 8,891 |
| WESTERN GUERNSEY REGIONAL WATER DISTRICT | 3,225 |
Frequently asked questions about Cambridge tap water
Is Cambridge tap water safe to drink?
EPA testing detected 20 contaminants in the water serving Cambridge. 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 Cambridge?
3 public water suppliers report drinking-water monitoring for Cambridge, Ohio to the EPA. Each is listed above with its population served.
What contaminants are in Cambridge's water?
The contaminants EPA monitoring detected in Cambridge include Fluoride, Nitrate, Copper, 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.