What was found in Oshkosh'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 | 1600 µg/L 16% of the EPA limit 10000 µg/L Main supplier: OSHKOSH WATERWORKS · 63,000 people · 2019 | 1/2 | SYR4 |
| Fluoride | 784.6 µg/L 20% of the EPA limit 4000 µg/L Main supplier: OSHKOSH WATERWORKS · 63,000 people · 2019
Highest in the city: 1233 µg/L — ALGOMA TN SANITARY DIST 1 · 3,935 people · 2017 | 2/2 | SYR4 |
| Copper | 590.5 µg/L 45% of the EPA limit 1300 µg/L Main supplier: OSHKOSH WATERWORKS · 63,000 people · 2017
Highest in the city: 627 µg/L — ALGOMA TN SANITARY DIST 1 · 3,935 people · 2017 | 2/2 | SYR4 |
| Nitrate-Nitrite | 596.5 µg/L 6% of the EPA limit 10000 µg/L Main supplier: OSHKOSH WATERWORKS · 63,000 people · 2017 | 1/2 | SYR4 |
| Barium | 22.9 µg/L 1.1% of the EPA limit 2000 µg/L Main supplier: OSHKOSH WATERWORKS · 63,000 people · 2017
Highest in the city: 100 µg/L — ALGOMA TN SANITARY DIST 1 · 3,935 people · 2017 | 2/2 | SYR4 |
| TTHM | 18.04 µg/L 23% of the EPA limit 80 µg/L Main supplier: OSHKOSH WATERWORKS · 63,000 people · 2019
Highest in the city: 24.9525 µg/L — ALGOMA TN SANITARY DIST 1 · 3,935 people · 2019 | 2/2 | SYR4 |
| Chloroform | 16 µg/L No EPA limit set Main supplier: OSHKOSH WATERWORKS · 63,000 people · 2019 | 2/2 | SYR4 |
| Lead | 14 µg/L 93% of the EPA limit 15 µg/L Main supplier: OSHKOSH WATERWORKS · 63,000 people · 2017 | 2/2 | SYR4 |
| Bromoform | 0.1450 µg/L No EPA limit set Main supplier: OSHKOSH WATERWORKS · 63,000 people · 2019
Highest in the city: 13.215 µg/L — ALGOMA TN SANITARY DIST 1 · 3,935 people · 2019 | 2/2 | SYR4 |
| Gross Alpha, Excl. Radon And U | 0.2400 pCi/L 1.6% of the EPA limit 15 pCi/L Main supplier: OSHKOSH WATERWORKS · 63,000 people · 2014
Highest in the city: 10.5395 pCi/L — ALGOMA TN SANITARY DIST 1 · 3,935 people · 2017 | 2/2 | SYR4 |
| Dibromochloromethane | 0.3000 µg/L No EPA limit set Main supplier: OSHKOSH WATERWORKS · 63,000 people · 2019
Highest in the city: 8.875 µg/L — ALGOMA TN SANITARY DIST 1 · 3,935 people · 2019 | 2/2 | SYR4 |
| Total Haloacetic Acids (HAA5) | 8.485 µg/L 14% of the EPA limit 60 µg/L Main supplier: OSHKOSH WATERWORKS · 63,000 people · 2019 | 2/2 | SYR4 |
| Dichloroacetic Acid | 7.67 µg/L No EPA limit set Main supplier: OSHKOSH WATERWORKS · 63,000 people · 2019 | 2/2 | SYR4 |
| Bromate | 5.25 µg/L 53% of the EPA limit 10 µg/L Main supplier: OSHKOSH WATERWORKS · 63,000 people · 2019 | 1/2 | SYR4 |
| Gross Beta Particle Activity | 4.831 pCi/L No EPA limit set Highest in the city: ALGOMA TN SANITARY DIST 1 · 3,935 people · 2014 | 1/2 | SYR4 |
| Bromodichloromethane | 2 µg/L No EPA limit set Main supplier: OSHKOSH WATERWORKS · 63,000 people · 2019
Highest in the city: 4.66 µg/L — ALGOMA TN SANITARY DIST 1 · 3,935 people · 2019 | 2/2 | SYR4 |
| Combined Radium (-226 And -228) | 0.8600 pCi/L 17% of the EPA limit 5 pCi/L Main supplier: OSHKOSH WATERWORKS · 63,000 people · 2014
Highest in the city: 4.0691 pCi/L — ALGOMA TN SANITARY DIST 1 · 3,935 people · 2017 | 2/2 | SYR4 |
| Monochloroacetic Acid | 3.05 µg/L No EPA limit set Main supplier: OSHKOSH WATERWORKS · 63,000 people · 2019 | 1/2 | SYR4 |
| Dibromoacetic Acid | 0.3000 µg/L No EPA limit set Main supplier: OSHKOSH WATERWORKS · 63,000 people · 2019
Highest in the city: 3 µg/L — ALGOMA TN SANITARY DIST 1 · 3,935 people · 2019 | 2/2 | SYR4 |
| Trichloroacetic Acid | 1.62 µg/L No EPA limit set Main supplier: OSHKOSH WATERWORKS · 63,000 people · 2019 | 2/2 | SYR4 |
| Cyanide | 1 µg/L 0.5% of the EPA limit 200 µg/L Main supplier: OSHKOSH WATERWORKS · 63,000 people · 2017 | 1/2 | SYR4 |
| Monobromoacetic Acid | 0.5820 µg/L No EPA limit set Main supplier: OSHKOSH WATERWORKS · 63,000 people · 2019 | 2/2 | SYR4 |
| Arsenic | 0.4000 µg/L 4% of the EPA limit 10 µg/L Main supplier: OSHKOSH WATERWORKS · 63,000 people · 2017 | 1/2 | SYR4 |
| Combined Uranium | 0.0900 µg/L 0.3% of the EPA limit 30 µg/L Main supplier: OSHKOSH WATERWORKS · 63,000 people · 2014 | 1/2 | SYR4 |
| Atrazine | 0.0200 µg/L 0.7% of the EPA limit 3 µg/L Main supplier: OSHKOSH WATERWORKS · 63,000 people · 2017 | 1/2 | SYR4 |
| Lead | 0.0061 mg/L 41% of the EPA limit 0.0150 mg/L Main supplier: OSHKOSH WATERWORKS · 63,000 people · 2025 | 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 Oshkosh
| Supplier | Population served |
|---|---|
| OSHKOSH WATERWORKS | 63,000 |
| ALGOMA TN SANITARY DIST 1 | 3,935 |
Frequently asked questions about Oshkosh tap water
Is Oshkosh tap water safe to drink?
EPA testing detected 26 contaminants in the water serving Oshkosh. 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 Oshkosh?
2 public water suppliers report drinking-water monitoring for Oshkosh, Wisconsin to the EPA. Each is listed above with its population served.
What contaminants are in Oshkosh's water?
The contaminants EPA monitoring detected in Oshkosh include Nitrate, Fluoride, Copper, Nitrate-Nitrite, 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.