What was found in Waukesha'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 | 170 µg/L 1.7% of the EPA limit 10000 µg/L Main supplier: WAUKESHA WATER UTILITY · 70,718 people · 2019
Highest in the city: 9230 µg/L — SCHOENSTATT SISTERS OF MARY · 80 people · 2017 | 2/2 | SYR4 |
| Nitrate-Nitrite | 100 µg/L 1% of the EPA limit 10000 µg/L Main supplier: WAUKESHA WATER UTILITY · 70,718 people · 2017
Highest in the city: 8555 µg/L — SCHOENSTATT SISTERS OF MARY · 80 people · 2019 | 2/2 | SYR4 |
| Fluoride | 912.5 µg/L 23% of the EPA limit 4000 µg/L Main supplier: WAUKESHA WATER UTILITY · 70,718 people · 2019 | 2/2 | SYR4 |
| Copper | 208 µg/L 16% of the EPA limit 1300 µg/L Main supplier: WAUKESHA WATER UTILITY · 70,718 people · 2017
Highest in the city: 496 µg/L — SCHOENSTATT SISTERS OF MARY · 80 people · 2019 | 2/2 | SYR4 |
| Barium | 170.5 µg/L 8.5% of the EPA limit 2000 µg/L Main supplier: WAUKESHA WATER UTILITY · 70,718 people · 2017 | 2/2 | SYR4 |
| Cyanide | 39.4 µg/L 20% of the EPA limit 200 µg/L Main supplier: WAUKESHA WATER UTILITY · 70,718 people · 2015 | 1/2 | SYR4 |
| Lead | 3.42 µg/L 23% of the EPA limit 15 µg/L Main supplier: WAUKESHA WATER UTILITY · 70,718 people · 2017
Highest in the city: 34.068 µg/L — SCHOENSTATT SISTERS OF MARY · 80 people · 2019 | 2/2 | SYR4 |
| Gross Alpha, Excl. Radon And U | 28.88 pCi/L 193% of the EPA limit, at the 95th percentile of samples — 15 pCi/L Main supplier: WAUKESHA WATER UTILITY · 70,718 people · 2019 | 2/2 | SYR4 |
| TTHM | 19.79 µg/L 25% of the EPA limit 80 µg/L Main supplier: WAUKESHA WATER UTILITY · 70,718 people · 2019 | 1/2 | SYR4 |
| Gross Beta Particle Activity | 18.505 pCi/L No EPA limit set Main supplier: WAUKESHA WATER UTILITY · 70,718 people · 2019 | 2/2 | SYR4 |
| Combined Radium (-226 And -228) | 12.0395 pCi/L 241% of the EPA limit, at the 95th percentile of samples — 5 pCi/L Main supplier: WAUKESHA WATER UTILITY · 70,718 people · 2019 | 2/2 | SYR4 |
| Bromodichloromethane | 6.4 µg/L No EPA limit set Main supplier: WAUKESHA WATER UTILITY · 70,718 people · 2019 | 1/2 | SYR4 |
| Chloroform | 6.26 µg/L No EPA limit set Main supplier: WAUKESHA WATER UTILITY · 70,718 people · 2019 | 1/2 | SYR4 |
| Dibromochloromethane | 5.36 µg/L No EPA limit set Main supplier: WAUKESHA WATER UTILITY · 70,718 people · 2019 | 1/2 | SYR4 |
| Total Haloacetic Acids (HAA5) | 3.9476 µg/L 6.6% of the EPA limit 60 µg/L Main supplier: WAUKESHA WATER UTILITY · 70,718 people · 2019 | 1/2 | SYR4 |
| Arsenic | 2.79 µg/L 28% of the EPA limit 10 µg/L Main supplier: WAUKESHA WATER UTILITY · 70,718 people · 2017 | 1/2 | SYR4 |
| Dichloroacetic Acid | 2.355 µg/L No EPA limit set Main supplier: WAUKESHA WATER UTILITY · 70,718 people · 2019 | 1/2 | SYR4 |
| Bromoform | 1.8715 µg/L No EPA limit set Main supplier: WAUKESHA WATER UTILITY · 70,718 people · 2019 | 1/2 | SYR4 |
| Dibromoacetic Acid | 1.51 µg/L No EPA limit set Main supplier: WAUKESHA WATER UTILITY · 70,718 people · 2019 | 1/2 | SYR4 |
| Combined Uranium | 1.35867 µg/L 4.5% of the EPA limit 30 µg/L Main supplier: WAUKESHA WATER UTILITY · 70,718 people · 2019 | 1/2 | SYR4 |
| Trichloroacetic Acid | 0.7350 µg/L No EPA limit set Main supplier: WAUKESHA WATER UTILITY · 70,718 people · 2019 | 1/2 | SYR4 |
| Monobromoacetic Acid | 0.4870 µg/L No EPA limit set Main supplier: WAUKESHA WATER UTILITY · 70,718 people · 2019 | 1/2 | SYR4 |
| Antimony, Total | 0.4200 µg/L 7% of the EPA limit 6 µg/L Main supplier: WAUKESHA WATER UTILITY · 70,718 people · 2017 | 1/2 | SYR4 |
| Lead | 0.00056 mg/L 3.7% of the EPA limit 0.0150 mg/L Main supplier: WAUKESHA WATER UTILITY · 70,718 people · 2024
Highest in the city: 0.0013 mg/L — SCHOENSTATT SISTERS OF MARY · 80 people · 2024 | 2/2 | 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 Waukesha
| Supplier | Population served |
|---|---|
| WAUKESHA WATER UTILITY | 70,718 |
| SCHOENSTATT SISTERS OF MARY | 80 |
Frequently asked questions about Waukesha tap water
Is Waukesha tap water safe to drink?
EPA testing detected 24 contaminants in the water serving Waukesha. 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 Waukesha?
2 public water suppliers report drinking-water monitoring for Waukesha, Wisconsin to the EPA. Each is listed above with its population served.
What contaminants are in Waukesha's water?
The contaminants EPA monitoring detected in Waukesha include Nitrate, Nitrate-Nitrite, Fluoride, Copper, Barium. 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.