What was found in Sauk'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 | 1089.5 µg/L 27% of the EPA limit 4000 µg/L Main supplier: SAUK · 9,921 people · 2018 | 1/2 | SYR4 |
| Copper | 865.45 µg/L 67% of the EPA limit 1300 µg/L Main supplier: SAUK · 9,921 people · 2017 | 2/2 | SYR4 |
| Nitrate | 122 µg/L 1.2% of the EPA limit 10000 µg/L Main supplier: SAUK · 9,921 people · 2019 | 1/2 | SYR4 |
| Lithium | 70.3 µg/L No EPA limit set Main supplier: SAUK · 9,921 people · 2025 | 1/2 | UCMR-5 |
| Nitrate-Nitrite | 69.5 µg/L 0.7% of the EPA limit 10000 µg/L Main supplier: SAUK · 9,921 people · 2016 | 1/2 | SYR4 |
| Barium | 61.775 µg/L 3.1% of the EPA limit 2000 µg/L Main supplier: SAUK · 9,921 people · 2018 | 1/2 | SYR4 |
| Lead | 41.1725 µg/L 274% of the EPA limit, at the 95th percentile of samples — 15 µg/L Main supplier: SAUK · 9,921 people · 2017 | 2/2 | SYR4 |
| Xylenes, Total | 26.422 µg/L 0.3% of the EPA limit 10000 µg/L Main supplier: SAUK · 9,921 people · 2019 | 1/2 | SYR4 |
| Nitrite | 21.525 µg/L 2.2% of the EPA limit 1000 µg/L Main supplier: SAUK · 9,921 people · 2018 | 1/2 | SYR4 |
| Ethylbenzene | 12.293 µg/L 1.8% of the EPA limit 700 µg/L Main supplier: SAUK · 9,921 people · 2019 | 1/2 | SYR4 |
| Vinyl Chloride | 7.678 µg/L 384% of the EPA limit, at the 95th percentile of samples — 2 µg/L Main supplier: SAUK · 9,921 people · 2019 | 1/2 | SYR4 |
| Toluene | 6.738 µg/L 0.7% of the EPA limit 1000 µg/L Main supplier: SAUK · 9,921 people · 2019 | 1/2 | SYR4 |
| TTHM | 4.371 µg/L 5.5% of the EPA limit 80 µg/L Main supplier: SAUK · 9,921 people · 2019
Highest in the city: 4.69 µg/L — WEATHERSTONE LAKES MHP · 221 people · 2018 | 2/2 | SYR4 |
| Total Haloacetic Acids (HAA5) | 4.507 µg/L 7.5% of the EPA limit 60 µg/L Main supplier: SAUK · 9,921 people · 2019 | 2/2 | SYR4 |
| Combined Radium (-226 And -228) | 3.757 pCi/L 75% of the EPA limit 5 pCi/L Main supplier: SAUK · 9,921 people · 2018 | 1/2 | SYR4 |
| cis-1,2-Dichloroethylene | 3.595 µg/L 5.1% of the EPA limit 70 µg/L Main supplier: SAUK · 9,921 people · 2019 | 1/2 | SYR4 |
| Monochloroacetic Acid | 2.2505 µg/L No EPA limit set Main supplier: SAUK · 9,921 people · 2019 | 1/2 | SYR4 |
| Selenium | 2.18 µg/L 4.4% of the EPA limit 50 µg/L Main supplier: SAUK · 9,921 people · 2018 | 1/2 | SYR4 |
| Dibromochloromethane | 1.5595 µg/L No EPA limit set Main supplier: SAUK · 9,921 people · 2019
Highest in the city: 1.7 µg/L — WEATHERSTONE LAKES MHP · 221 people · 2018 | 2/2 | SYR4 |
| Bromoform | 1.5905 µg/L No EPA limit set Main supplier: SAUK · 9,921 people · 2019 | 2/2 | SYR4 |
| Bromodichloromethane | 1.239 µg/L No EPA limit set Main supplier: SAUK · 9,921 people · 2019
Highest in the city: 1.59 µg/L — WEATHERSTONE LAKES MHP · 221 people · 2018 | 2/2 | SYR4 |
| Dichloroacetic Acid | 1.421 µg/L No EPA limit set Main supplier: SAUK · 9,921 people · 2019 | 1/2 | SYR4 |
| Arsenic | 1.40175 µg/L 14% of the EPA limit 10 µg/L Main supplier: SAUK · 9,921 people · 2018 | 1/2 | SYR4 |
| Dibromoacetic Acid | 0.9752 µg/L No EPA limit set Main supplier: SAUK · 9,921 people · 2019
Highest in the city: 1.2 µg/L — WEATHERSTONE LAKES MHP · 221 people · 2018 | 2/2 | SYR4 |
| Trichloroacetic Acid | 1.2 µg/L No EPA limit set Main supplier: SAUK · 9,921 people · 2019 | 1/2 | SYR4 |
| Monobromoacetic Acid | 1.1805 µg/L No EPA limit set Main supplier: SAUK · 9,921 people · 2019 | 1/2 | SYR4 |
| Dichloromethane | 1.0425 µg/L 21% of the EPA limit 5 µg/L Main supplier: SAUK · 9,921 people · 2019 | 1/2 | SYR4 |
| Lead | 0.0 mg/L 0% of the EPA limit 0.0150 mg/L Main supplier: SAUK · 9,921 people · 2023 | 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 Sauk
| Supplier | Population served |
|---|---|
| SAUK | 9,921 |
| WEATHERSTONE LAKES MHP | 221 |
Frequently asked questions about Sauk tap water
Is Sauk tap water safe to drink?
EPA testing detected 28 contaminants in the water serving Sauk. 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 Sauk?
2 public water suppliers report drinking-water monitoring for Sauk, Illinois to the EPA. Each is listed above with its population served.
What contaminants are in Sauk's water?
The contaminants EPA monitoring detected in Sauk include Fluoride, Copper, Nitrate, Lithium, Nitrate-Nitrite. 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.