What was found in Mequon'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-Nitrite | 6716.6 µg/L 67% of the EPA limit 10000 µg/L Highest in the city: PARK PLACE SUBDIVISION · 260 people · 2019 | 7/23 | SYR4 |
| Fluoride | 1275 µg/L 32% of the EPA limit 4000 µg/L Highest in the city: WYNGATE SUBDIVISION · 100 people · 2018 | 22/23 | SYR4 |
| Copper | 136 µg/L 10% of the EPA limit 1300 µg/L Main supplier: MEQUON WATER UTILITY · 11,152 people · 2017
Highest in the city: 1020 µg/L — WYNGATE SUBDIVISION · 100 people · 2018 | 23/23 | SYR4 |
| Nitrate | 520 µg/L 5.2% of the EPA limit 10000 µg/L Highest in the city: CONCORDIA UNIVERSITY · 1,500 people · 2019 | 14/23 | SYR4 |
| Barium | 120.9 µg/L 6% of the EPA limit 2000 µg/L Highest in the city: WOODRIDGE ESTATES · 100 people · 2018 | 22/23 | SYR4 |
| Lead | 4.2 µg/L 28% of the EPA limit 15 µg/L Main supplier: MEQUON WATER UTILITY · 11,152 people · 2017
Highest in the city: 39.1 µg/L — RAVINE FARMS HM OWNERS ASSOC · 100 people · 2019 | 22/23 | SYR4 |
| TTHM | 14.0275 µg/L 18% of the EPA limit 80 µg/L Main supplier: MEQUON WATER UTILITY · 11,152 people · 2019
Highest in the city: 26.6 µg/L — CONCORDIA UNIVERSITY · 1,500 people · 2019 | 2/23 | SYR4 |
| Chloroform | 6.225 µg/L No EPA limit set Main supplier: MEQUON WATER UTILITY · 11,152 people · 2019
Highest in the city: 16.8 µg/L — CONCORDIA UNIVERSITY · 1,500 people · 2019 | 4/23 | SYR4 |
| Nitrite | 14.7 µg/L 1.5% of the EPA limit 1000 µg/L Highest in the city: PARK PLACE SUBDIVISION · 260 people · 2018 | 1/23 | SYR4 |
| Di(2-ethylhexyl) Phthalate | 11 µg/L 183% of the EPA limit, at the 95th percentile of samples — 6 µg/L Highest in the city: BRIGHTON RIDGE SUBDIVISION · 200 people · 2019 | 1/23 | SYR4 |
| Total Haloacetic Acids (HAA5) | 5.299 µg/L 8.8% of the EPA limit 60 µg/L Main supplier: MEQUON WATER UTILITY · 11,152 people · 2019
Highest in the city: 9.9075 µg/L — CONCORDIA UNIVERSITY · 1,500 people · 2019 | 2/23 | SYR4 |
| Arsenic | 7.37 µg/L 74% of the EPA limit 10 µg/L Highest in the city: MEQUON ON THE SQUARE CONDOMINIUM OWNERS ASSOCIATION INC · 110 people · 2018 | 17/23 | SYR4 |
| Bromodichloromethane | 4.715 µg/L No EPA limit set Main supplier: MEQUON WATER UTILITY · 11,152 people · 2019
Highest in the city: 6.595 µg/L — CONCORDIA UNIVERSITY · 1,500 people · 2019 | 2/23 | SYR4 |
| Dichloroacetic Acid | 2.97 µg/L No EPA limit set Main supplier: MEQUON WATER UTILITY · 11,152 people · 2019
Highest in the city: 5.25 µg/L — CONCORDIA UNIVERSITY · 1,500 people · 2019 | 2/23 | SYR4 |
| Combined Radium (-226 And -228) | 5.144 pCi/L 103% of the EPA limit, at the 95th percentile of samples — 5 pCi/L Highest in the city: RIVER LAKE SUBDIVISION · 100 people · 2017 | 22/23 | SYR4 |
| Gross Alpha, Excl. Radon And U | 4.8 pCi/L 32% of the EPA limit 15 pCi/L Highest in the city: RIVER LAKE SUBDIVISION · 100 people · 2015 | 12/23 | SYR4 |
| Chromium | 4.09 µg/L 4.1% of the EPA limit 100 µg/L Highest in the city: RIVER LAKE SUBDIVISION · 100 people · 2018 | 10/23 | SYR4 |
| Trichloroacetic Acid | 1.555 µg/L No EPA limit set Main supplier: MEQUON WATER UTILITY · 11,152 people · 2019
Highest in the city: 3.7 µg/L — CONCORDIA UNIVERSITY · 1,500 people · 2019 | 2/23 | SYR4 |
| Dibromochloromethane | 2.915 µg/L No EPA limit set Main supplier: MEQUON WATER UTILITY · 11,152 people · 2019
Highest in the city: 3.33 µg/L — CONCORDIA UNIVERSITY · 1,500 people · 2019 | 2/23 | SYR4 |
| Dibromoacetic Acid | 0.7040 µg/L No EPA limit set Main supplier: MEQUON WATER UTILITY · 11,152 people · 2019
Highest in the city: 0.7625 µg/L — CONCORDIA UNIVERSITY · 1,500 people · 2019 | 2/23 | SYR4 |
| Monobromoacetic Acid | 0.5360 µg/L No EPA limit set Main supplier: MEQUON WATER UTILITY · 11,152 people · 2019 | 2/23 | SYR4 |
| Cadmium | 0.3400 µg/L 6.8% of the EPA limit 5 µg/L Highest in the city: BRIGHTON RIDGE SUBDIVISION · 200 people · 2018 | 2/23 | SYR4 |
| Styrene | 0.3300 µg/L 0.3% of the EPA limit 100 µg/L Highest in the city: COUNTRY TERRACE CONDO HOMES · 160 people · 2018 | 1/23 | SYR4 |
| Lead | 0.00052 mg/L 3.5% of the EPA limit 0.0150 mg/L Main supplier: MEQUON WATER UTILITY · 11,152 people · 2023
Highest in the city: 0.0029 mg/L — COUNTRY TERRACE CONDO HOMES · 160 people · 2024 | 23/23 | 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 Mequon
| Supplier | Population served |
|---|---|
| MEQUON WATER UTILITY | 11,152 |
| CONCORDIA UNIVERSITY | 1,500 |
| MEQUON TRAIL TOWNHOMES | 615 |
| HUNTINGTON PARK | 600 |
| BEECHWOOD FARMS ESTATES | 300 |
| WESTCHESTER LAKES SUBDIVISION | 300 |
| PARK PLACE SUBDIVISION | 260 |
| PINES SUBDIVISION | 200 |
| BRIGHTON RIDGE SUBDIVISION | 200 |
| HADDONSTONE SUBDIVISION | 195 |
| COUNTRY TERRACE CONDO HOMES | 160 |
| VINTAGE ESTATES | 130 |
| KENILWORTH SUBD | 120 |
| MEQUON ON THE SQUARE CONDOMINIUM OWNERS ASSOCIATION INC | 110 |
| WOODRIDGE ESTATES | 100 |
| RIVER LAKE SUBDIVISION | 100 |
| WYNGATE SUBDIVISION | 100 |
| RAVINE FARMS HM OWNERS ASSOC | 100 |
| HIGHLAND COLONY ESTATES CONDO | 88 |
| RIVER TRAILS ESTATES WATER USERS | 84 |
| MEQUON COLONY ESTATES | 75 |
| MEQUON PARC APARTMENTS LLC | 60 |
| MEQUON WATER TRUST | 26 |
Frequently asked questions about Mequon tap water
Is Mequon tap water safe to drink?
EPA testing detected 24 contaminants in the water serving Mequon. 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 Mequon?
23 public water suppliers report drinking-water monitoring for Mequon, Wisconsin to the EPA. Each is listed above with its population served.
What contaminants are in Mequon's water?
The contaminants EPA monitoring detected in Mequon include Nitrate-Nitrite, Fluoride, Copper, Nitrate, 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.