What was found in Norwalk'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 | 1035.85 µg/L 26% of the EPA limit 4000 µg/L Highest in the city: NORWALK CITY PWS · 17,466 people · 2019 | 1/5 | SYR4 |
| Nitrate-Nitrite | 986 µg/L 9.9% of the EPA limit 10000 µg/L Highest in the city: NORWALK CITY PWS · 17,466 people · 2019 | 1/5 | SYR4 |
| Nitrate | 980.5 µg/L 9.8% of the EPA limit 10000 µg/L Highest in the city: NORWALK CITY PWS · 17,466 people · 2019 | 1/5 | SYR4 |
| Copper | 226 µg/L 17% of the EPA limit 1300 µg/L Main supplier: NORTHERN OHIO RURAL WATER · 18,224 people · 2019
Highest in the city: 250.8 µg/L — NORWALK CITY PWS · 17,466 people · 2019 | 4/5 | SYR4 |
| TTHM | 78.77 µg/L 98% of the EPA limit 80 µg/L Main supplier: NORTHERN OHIO RURAL WATER · 18,224 people · 2019
Highest in the city: 101.465 µg/L — NORTHERN OHIO RURAL WATER-SOUTH DISTRICT · 5,226 people · 2019 | 4/5 | SYR4 |
| Chloroform | 57.095 µg/L No EPA limit set Main supplier: NORTHERN OHIO RURAL WATER · 18,224 people · 2019
Highest in the city: 77 µg/L — NORTHERN OHIO RURAL WATER-SOUTH DISTRICT · 5,226 people · 2019 | 4/5 | SYR4 |
| Total Haloacetic Acids (HAA5) | 47.185 µg/L 79% of the EPA limit 60 µg/L Main supplier: NORTHERN OHIO RURAL WATER · 18,224 people · 2019
Highest in the city: 53.255 µg/L — NORTHERN OHIO RURAL WATER-SOUTH DISTRICT · 5,226 people · 2019 | 4/5 | SYR4 |
| Lead | 51.01 µg/L 340% of the EPA limit, at the 95th percentile of samples — 15 µg/L Main supplier: NORTHERN OHIO RURAL WATER · 18,224 people · 2019
Highest in the city: 51.9 µg/L — NORTHERN OHIO RURAL WATER-SOUTH DISTRICT · 5,226 people · 2019 | 4/5 | SYR4 |
| Dichloroacetic Acid | 23.055 µg/L No EPA limit set Main supplier: NORTHERN OHIO RURAL WATER · 18,224 people · 2019
Highest in the city: 29.21 µg/L — NORTHERN OHIO RURAL WATER-SOUTH DISTRICT · 5,226 people · 2019 | 4/5 | SYR4 |
| Trichloroacetic Acid | 23.585 µg/L No EPA limit set Main supplier: NORTHERN OHIO RURAL WATER · 18,224 people · 2019
Highest in the city: 24.97 µg/L — NORTHERN OHIO RURAL WATER-SOUTH DISTRICT · 5,226 people · 2019 | 4/5 | SYR4 |
| Barium | 20.95 µg/L 1% of the EPA limit 2000 µg/L Highest in the city: NORWALK CITY PWS · 17,466 people · 2019 | 1/5 | SYR4 |
| Bromodichloromethane | 17.425 µg/L No EPA limit set Main supplier: NORTHERN OHIO RURAL WATER · 18,224 people · 2019
Highest in the city: 20.055 µg/L — NORTHERN OHIO RURAL WATER-SOUTH DISTRICT · 5,226 people · 2019 | 4/5 | SYR4 |
| Dibromochloromethane | 5.63 µg/L No EPA limit set Main supplier: NORTHERN OHIO RURAL WATER · 18,224 people · 2019
Highest in the city: 7.71 µg/L — NORTHERN OHIO RURAL WATER-SOUTH DISTRICT · 5,226 people · 2019 | 4/5 | SYR4 |
| Monochloroacetic Acid | 5.18 µg/L No EPA limit set Main supplier: NORTHERN OHIO RURAL WATER · 18,224 people · 2019 | 4/5 | SYR4 |
| Gross Beta Particle Activity | 4.1 pCi/L No EPA limit set Highest in the city: NORWALK CITY PWS · 17,466 people · 2015 | 1/5 | SYR4 |
| Dibromoacetic Acid | 2.13 µg/L No EPA limit set Main supplier: NORTHERN OHIO RURAL WATER · 18,224 people · 2019
Highest in the city: 2.8 µg/L — NORTHERN OHIO RURAL WATER-SOUTH DISTRICT · 5,226 people · 2019 | 3/5 | SYR4 |
| Bromoform | 0.8750 µg/L No EPA limit set Main supplier: NORTHERN OHIO RURAL WATER · 18,224 people · 2019
Highest in the city: 1 µg/L — NORTHERN OHIO RURAL WATER-SOUTH DISTRICT · 5,226 people · 2019 | 3/5 | SYR4 |
| Monobromoacetic Acid | 1 µg/L No EPA limit set Highest in the city: NORTHERN OHIO RURAL WATER-SOUTH DISTRICT · 5,226 people · 2019 | 1/5 | SYR4 |
| Atrazine | 0.3730 µg/L 12% of the EPA limit 3 µg/L Highest in the city: NORWALK CITY PWS · 17,466 people · 2019 | 1/5 | SYR4 |
| Simazine | 0.3620 µg/L 9% of the EPA limit 4 µg/L Highest in the city: NORWALK CITY PWS · 17,466 people · 2019 | 1/5 | SYR4 |
| Pfba | 0.0156 µg/L No EPA limit set Highest in the city: NORTHERN OHIO RURAL WATER-SOUTH DISTRICT · 5,226 people · 2023 | 2/5 | UCMR-5 |
| Lead | 0.0040 mg/L 27% of the EPA limit 0.0150 mg/L Main supplier: NORTHERN OHIO RURAL WATER · 18,224 people · 2025 | 5/5 | 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 Norwalk
| Supplier | Population served |
|---|---|
| NORTHERN OHIO RURAL WATER | 18,224 |
| NORWALK CITY PWS | 17,466 |
| NORTHERN OHIO RURAL WATER-SOUTH DISTRICT | 5,226 |
| NORTHERN OHIO RURAL WATER - CAMP ROAD | 758 |
| NORTHERN OHIO RURAL WATER - SE DISTRICT | 586 |
Frequently asked questions about Norwalk tap water
Is Norwalk tap water safe to drink?
EPA testing detected 22 contaminants in the water serving Norwalk. 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 Norwalk?
5 public water suppliers report drinking-water monitoring for Norwalk, Ohio to the EPA. Each is listed above with its population served.
What contaminants are in Norwalk's water?
The contaminants EPA monitoring detected in Norwalk include Fluoride, Nitrate-Nitrite, Nitrate, Copper, 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.