What was found in ZIP 78683
The level at this ZIP's main supplier, the highest level anywhere in it, the EPA limit for each, and where the figure comes from.
| Contaminant | Level vs EPA limit | Suppliers | Source |
|---|---|---|---|
| Nitrate | 5790 µg/L 58% of the EPA limit 10000 µg/L Main supplier: CITY OF ROUND ROCK · 130,662 people · 2019 | 2/2 | SYR4 |
| Nitrate-Nitrite | 5730 µg/L 57% of the EPA limit 10000 µg/L Main supplier: CITY OF ROUND ROCK · 130,662 people · 2015 | 2/2 | SYR4 |
| Fluoride | 315 µg/L 7.9% of the EPA limit 4000 µg/L Main supplier: CITY OF ROUND ROCK · 130,662 people · 2019
Highest in the ZIP: 1625 µg/L — MANVILLE WSC · 39,648 people · 2019 | 2/2 | SYR4 |
| Copper | 400 µg/L 31% of the EPA limit 1300 µg/L Main supplier: CITY OF ROUND ROCK · 130,662 people · 2018 | 2/2 | SYR4 |
| Nitrite | 185 µg/L 19% of the EPA limit 1000 µg/L Highest in the ZIP: MANVILLE WSC · 39,648 people · 2015 | 1/2 | SYR4 |
| Xylenes, Total | 142.25 µg/L 1.4% of the EPA limit 10000 µg/L Highest in the ZIP: MANVILLE WSC · 39,648 people · 2019 | 1/2 | SYR4 |
| Barium | 53.5 µg/L 2.7% of the EPA limit 2000 µg/L Main supplier: CITY OF ROUND ROCK · 130,662 people · 2019
Highest in the ZIP: 142 µg/L — MANVILLE WSC · 39,648 people · 2019 | 2/2 | SYR4 |
| Cyanide | 115 µg/L 57% of the EPA limit 200 µg/L Main supplier: CITY OF ROUND ROCK · 130,662 people · 2019
Highest in the ZIP: 117.1 µg/L — MANVILLE WSC · 39,648 people · 2019 | 2/2 | SYR4 |
| Lithium | 13.5 µg/L No EPA limit set Main supplier: CITY OF ROUND ROCK · 130,662 people · 2025
Highest in the ZIP: 83.8 µg/L — MANVILLE WSC · 39,648 people · 2023 | 2/2 | UCMR-5 |
| TTHM | 64.13999999999999 µg/L 80% of the EPA limit 80 µg/L Main supplier: CITY OF ROUND ROCK · 130,662 people · 2019
Highest in the ZIP: 64.84999999999997 µg/L — MANVILLE WSC · 39,648 people · 2019 | 2/2 | SYR4 |
| Ethylbenzene | 28.25 µg/L 4% of the EPA limit 700 µg/L Highest in the ZIP: MANVILLE WSC · 39,648 people · 2019 | 1/2 | SYR4 |
| Total Haloacetic Acids (HAA5) | 25.639999999999986 µg/L 43% of the EPA limit 60 µg/L Main supplier: CITY OF ROUND ROCK · 130,662 people · 2019 | 2/2 | SYR4 |
| Bromodichloromethane | 24.009999999999998 µg/L No EPA limit set Main supplier: CITY OF ROUND ROCK · 130,662 people · 2019
Highest in the ZIP: 24.020000000000017 µg/L — MANVILLE WSC · 39,648 people · 2019 | 2/2 | SYR4 |
| Dibromochloromethane | 23.4 µg/L No EPA limit set Main supplier: CITY OF ROUND ROCK · 130,662 people · 2019 | 2/2 | SYR4 |
| Chloroform | 19.889999999999997 µg/L No EPA limit set Main supplier: CITY OF ROUND ROCK · 130,662 people · 2019 | 2/2 | SYR4 |
| Bromoform | 17.544999999999995 µg/L No EPA limit set Main supplier: CITY OF ROUND ROCK · 130,662 people · 2019 | 2/2 | SYR4 |
| Dichloroacetic Acid | 13 µg/L No EPA limit set Main supplier: CITY OF ROUND ROCK · 130,662 people · 2019 | 2/2 | SYR4 |
| Dibromoacetic Acid | 9.42 µg/L No EPA limit set Main supplier: CITY OF ROUND ROCK · 130,662 people · 2019 | 2/2 | SYR4 |
| Trichloroacetic Acid | 8.344999999999999 µg/L No EPA limit set Main supplier: CITY OF ROUND ROCK · 130,662 people · 2019
Highest in the ZIP: 8.645 µg/L — MANVILLE WSC · 39,648 people · 2019 | 2/2 | SYR4 |
| Lead | 7.909999999999989 µg/L 53% of the EPA limit 15 µg/L Main supplier: CITY OF ROUND ROCK · 130,662 people · 2018 | 2/2 | SYR4 |
| Selenium | 4.38 µg/L 8.8% of the EPA limit 50 µg/L Main supplier: CITY OF ROUND ROCK · 130,662 people · 2019
Highest in the ZIP: 6.5249999999999995 µg/L — MANVILLE WSC · 39,648 people · 2019 | 2/2 | SYR4 |
| Gross Alpha, Excl. Radon And U | 6.359999999999999 pCi/L 42% of the EPA limit 15 pCi/L Highest in the ZIP: MANVILLE WSC · 39,648 people · 2019 | 1/2 | SYR4 |
| Monochloroacetic Acid | 5.319999999999999 µg/L No EPA limit set Main supplier: CITY OF ROUND ROCK · 130,662 people · 2019 | 2/2 | SYR4 |
| Gross Beta Particle Activity | 4.4 pCi/L No EPA limit set Highest in the ZIP: MANVILLE WSC · 39,648 people · 2019 | 1/2 | SYR4 |
| Chromium | 4.0695 µg/L 4.1% of the EPA limit 100 µg/L Highest in the ZIP: MANVILLE WSC · 39,648 people · 2019 | 1/2 | SYR4 |
| Arsenic | 1.68 µg/L 17% of the EPA limit 10 µg/L Main supplier: CITY OF ROUND ROCK · 130,662 people · 2019
Highest in the ZIP: 2.665 µg/L — MANVILLE WSC · 39,648 people · 2019 | 2/2 | SYR4 |
| Combined Uranium | 2.3 µg/L 7.7% of the EPA limit 30 µg/L Highest in the ZIP: MANVILLE WSC · 39,648 people · 2019 | 1/2 | SYR4 |
| Combined Radium (-226 And -228) | 2.1079999999999997 pCi/L 42% of the EPA limit 5 pCi/L Highest in the ZIP: MANVILLE WSC · 39,648 people · 2017 | 1/2 | SYR4 |
| Monobromoacetic Acid | 2 µg/L No EPA limit set Main supplier: CITY OF ROUND ROCK · 130,662 people · 2019 | 2/2 | SYR4 |
| Atrazine | 0.1795 µg/L 6% of the EPA limit 3 µg/L Main supplier: CITY OF ROUND ROCK · 130,662 people · 2019
Highest in the ZIP: 0.6525 µg/L — MANVILLE WSC · 39,648 people · 2019 | 2/2 | SYR4 |
| Simazine | 0.1480 µg/L 3.7% of the EPA limit 4 µg/L Highest in the ZIP: MANVILLE WSC · 39,648 people · 2019 | 1/2 | SYR4 |
| PFNA | 0.0243 µg/L No EPA limit set Highest in the ZIP: MANVILLE WSC · 39,648 people · 2023 | 1/2 | UCMR-5 |
| PFOS | 0.0124 µg/L No EPA limit set Highest in the ZIP: MANVILLE WSC · 39,648 people · 2023 | 1/2 | UCMR-5 |
| PFBS | 0.0067 µg/L No EPA limit set Main supplier: CITY OF ROUND ROCK · 130,662 people · 2025
Highest in the ZIP: 0.0100 µg/L — MANVILLE WSC · 39,648 people · 2023 | 2/2 | UCMR-5 |
| Pfpea | 0.0067 µg/L No EPA limit set Main supplier: CITY OF ROUND ROCK · 130,662 people · 2025
Highest in the ZIP: 0.0091 µg/L — MANVILLE WSC · 39,648 people · 2023 | 2/2 | UCMR-5 |
| Pfhxa | 0.0037 µg/L No EPA limit set Main supplier: CITY OF ROUND ROCK · 130,662 people · 2025
Highest in the ZIP: 0.0087 µg/L — MANVILLE WSC · 39,648 people · 2023 | 2/2 | UCMR-5 |
| Pfba | 0.0051 µg/L No EPA limit set Main supplier: CITY OF ROUND ROCK · 130,662 people · 2025
Highest in the ZIP: 0.0074 µg/L — MANVILLE WSC · 39,648 people · 2023 | 2/2 | UCMR-5 |
| PFHXS | 0.0070 µg/L No EPA limit set Highest in the ZIP: MANVILLE WSC · 39,648 people · 2023 | 1/2 | UCMR-5 |
| PFOA | 0.0059 µg/L No EPA limit set Highest in the ZIP: MANVILLE WSC · 39,648 people · 2023 | 1/2 | UCMR-5 |
| Lead | 0.0050 mg/L 34% of the EPA limit 0.0150 mg/L Main supplier: CITY OF ROUND ROCK · 130,662 people · 2023 | 2/2 | LCR |
| Pfhpa | 0.0043 µg/L No EPA limit set Highest in the ZIP: MANVILLE WSC · 39,648 people · 2023 | 1/2 | UCMR-5 |
| Pfuna | 0.0027 µg/L No EPA limit set Highest in the ZIP: MANVILLE WSC · 39,648 people · 2023 | 1/2 | UCMR-5 |
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.
Water suppliers serving ZIP 78683
| Supplier | State | Population served |
|---|---|---|
| CITY OF ROUND ROCK | TX | 130,662 |
| MANVILLE WSC | TX | 39,648 |
Frequently asked questions about ZIP 78683 tap water
Is the tap water in ZIP 78683 safe to drink?
EPA testing detected 42 contaminants across the water suppliers serving ZIP 78683. A detection isn't the same as a violation — most levels are within federal limits. See each level and source above, and your utility's annual Consumer Confidence Report for the official status.
Which water suppliers serve ZIP 78683?
2 public water suppliers report EPA drinking-water monitoring for ZIP 78683. Each is listed above with its population served.
What contaminants are in ZIP 78683's water?
EPA monitoring detected Nitrate, Nitrate-Nitrite, Fluoride, Copper, Nitrite, and others across this ZIP's suppliers. The full list with levels and sources is above.