Compliance record
Formal violations the EPA has on file for this supplier. A health-based violation means a contaminant limit or a required treatment was breached; the rest are monitoring or reporting failures — still violations, but not a measured health risk.
14
health-based violations
26
violations on file
0
still open
| Violation | Type | Status | Period |
|---|---|---|---|
| TT | Health-based | Resolved | 2025-05-01 → 2025-05-31 |
| TT | Health-based | Resolved | 2025-05-01 → 2025-05-31 |
| TT | Health-based | Resolved | 2025-05-01 → 2025-05-31 |
| TT | Health-based | Resolved | 2025-05-01 → 2025-05-31 |
| MCL | Health-based | Resolved | 2015-05-01 → 2015-05-31 |
| MCL | Health-based | Resolved | 2015-05-01 → 2015-05-31 |
| MCL | Health-based | Resolved | 2015-05-01 → 2015-05-31 |
| MCL | Health-based | Resolved | 2015-05-01 → 2015-05-31 |
| MCL | Health-based | Resolved | 2015-04-01 → 2015-04-30 |
| MCL | Health-based | Resolved | 2015-04-01 → 2015-04-30 |
PFAS detected
PFAS are industrial “forever chemicals”. These are the EPA's latest
nationwide test results (2023–2025).
Other contaminants detected
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 this
system's samples — over 100% is worth reading, but is not by itself a
violation. Where a single sample came in higher than that percentile, it
is noted under the bar. Formal violations are listed separately.
| Contaminant | Level vs EPA limit | Detection rate | Source | Period |
|---|---|---|---|---|
| Bromodichloromethane | 12.9 µg/L No EPA limit set
worst single sample: 16.6 µg/L | 613/773 | SYR4 | 2012–2019 |
| Chloroform | 40.95 µg/L No EPA limit set
worst single sample: 67.3 µg/L | 607/773 | SYR4 | 2012–2019 |
| Nitrate | 780 µg/L 7.8% of the EPA limit 10000 µg/L
worst single sample: 1230 µg/L | 536/712 | SYR4 | 2012–2019 |
| Dibromochloromethane | 5.2 µg/L No EPA limit set
worst single sample: 20 µg/L | 525/773 | SYR4 | 2012–2019 |
| TTHM | 49.635 µg/L 62% of the EPA limit 80 µg/L
worst single sample: 75.8 µg/L | 514/518 | SYR4 | 2012–2019 |
| Total Haloacetic Acids (HAA5) | 49.97 µg/L 83% of the EPA limit 60 µg/L
worst single sample: 73.1 µg/L | 504/518 | SYR4 | 2012–2019 |
| Dichloroacetic Acid | 36.39 µg/L No EPA limit set
worst single sample: 50.9 µg/L | 503/518 | SYR4 | 2012–2019 |
| Trichloroacetic Acid | 12.33 µg/L No EPA limit set
worst single sample: 21.5 µg/L | 495/518 | SYR4 | 2012–2019 |
| Dibromoacetic Acid | 3.43 µg/L No EPA limit set
worst single sample: 13.3 µg/L | 299/518 | SYR4 | 2012–2019 |
| Copper | 338 µg/L 26% of the EPA limit 1300 µg/L
worst single sample: 1930 µg/L | 221/309 | SYR4 | 2012–2019 |
| Barium | 365.4 µg/L 18% of the EPA limit 2000 µg/L
worst single sample: 400 µg/L | 155/155 | SYR4 | 2012–2019 |
| Fluoride | 538 µg/L 13% of the EPA limit 4000 µg/L
worst single sample: 760 µg/L | 153/158 | SYR4 | 2012–2019 |
| Atrazine | 0.4650 µg/L 16% of the EPA limit 3 µg/L
worst single sample: 0.9100 µg/L | 96/227 | SYR4 | 2012–2019 |
| Monochloroacetic Acid | 9.275 µg/L No EPA limit set
worst single sample: 11.9 µg/L | 96/518 | SYR4 | 2012–2019 |
| Arsenic | 7.08 µg/L 71% of the EPA limit 10 µg/L
worst single sample: 11 µg/L | 85/161 | SYR4 | 2012–2019 |
| Bromoform | 8.655 µg/L No EPA limit set
worst single sample: 11 µg/L | 84/773 | SYR4 | 2012–2019 |
| Lead | 10.74 µg/L 72% of the EPA limit 15 µg/L
worst single sample: 48.9 µg/L | 77/309 | SYR4 | 2012–2019 |
| Nitrate-Nitrite | 310 µg/L 3.1% of the EPA limit 10000 µg/L
worst single sample: 350 µg/L | 69/95 | SYR4 | 2012–2019 |
| Lithium | 33.9 µg/L No EPA limit set | 69/96 | UCMR-5 | 2025 |
| Simazine | 0.2030 µg/L 5.1% of the EPA limit 4 µg/L
worst single sample: 0.2900 µg/L | 58/227 | SYR4 | 2012–2019 |
| Gross Alpha, Excl. Radon And U | 10.67 pCi/L 71% of the EPA limit 15 pCi/L
worst single sample: 11.1 pCi/L | 52/68 | SYR4 | 2013–2019 |
| Combined Radium (-226 And -228) | 3.63 pCi/L 73% of the EPA limit 5 pCi/L
worst single sample: 5.3 pCi/L | 48/63 | SYR4 | 2012–2019 |
| Selenium | 10.56 µg/L 21% of the EPA limit 50 µg/L
worst single sample: 12.9 µg/L | 39/155 | SYR4 | 2012–2019 |
| Combined Uranium | 10.77 µg/L 36% of the EPA limit 30 µg/L
worst single sample: 16.9 µg/L | 35/68 | SYR4 | 2013–2019 |
| Gross Beta Particle Activity | 7.23 pCi/L No EPA limit set
worst single sample: 8.7 pCi/L | 35/77 | SYR4 | 2012–2019 |
| Cyanide | 93.5 µg/L 47% of the EPA limit 200 µg/L
worst single sample: 110 µg/L | 34/117 | SYR4 | 2014–2019 |
| Xylenes, Total | 8.975 µg/L 0.1% of the EPA limit 10000 µg/L
worst single sample: 13 µg/L | 30/257 | SYR4 | 2012–2019 |
| Lead | 0.0050 mg/L 33% of the EPA limit 0.0150 mg/L | 17/17 | LCR | 2024 |
| Di(2-ethylhexyl) Phthalate | 1.58 µg/L 26% of the EPA limit 6 µg/L
worst single sample: 1.8 µg/L | 12/226 | SYR4 | 2012–2019 |
| Nitrite | 36.5 µg/L 3.7% of the EPA limit 1000 µg/L
worst single sample: 40 µg/L | 8/108 | SYR4 | 2012–2019 |
| Ethylbenzene | 2.075 µg/L 0.3% of the EPA limit 700 µg/L
worst single sample: 2.2 µg/L | 6/257 | SYR4 | 2012–2019 |
| Hexachlorocyclopentadiene | 0.2150 µg/L 0.4% of the EPA limit 50 µg/L
worst single sample: 0.2400 µg/L | 6/227 | SYR4 | 2012–2019 |
| Monobromoacetic Acid | 3.975 µg/L No EPA limit set
worst single sample: 4.5 µg/L | 4/518 | SYR4 | 2012–2019 |
| Chromium | 14.11 µg/L 14% of the EPA limit 100 µg/L
worst single sample: 14.3 µg/L | 3/155 | SYR4 | 2012–2019 |
| Benzo(A)Pyrene | 0.0400 µg/L 20% of the EPA limit 0.2000 µg/L | 1/227 | SYR4 | 2012–2019 |
| Dichloromethane | 0.5000 µg/L 10% of the EPA limit 5 µg/L | 1/257 | SYR4 | 2012–2019 |
| Endrin | 0.0100 µg/L 0.5% of the EPA limit 2 µg/L | 1/227 | SYR4 | 2012–2019 |
| Toluene | 1 µg/L 0.1% of the EPA limit 1000 µg/L | 1/257 | SYR4 | 2012–2019 |
67 contaminants tested, none detected
1,1,1-Trichloroethane1,1,2-Trichloroethane1,1-Dichloroethylene1,2,4-Trichlorobenzene1,2-DIBROMO-3-CHLOROPROPANE1,2-Dichloroethane1,2-Dichloropropane11Cl-PF3OUdS2,4,5-TP2,4-D4:2 Fts8:2 Fts9Cl-PF3ONSAdonaAntimony, TotalAsbestosBhc-GammaBenzeneBeryllium, TotalChlorobenzeneCadmiumCarbofuranCarbon TetrachlorideChlordaneDalaponDi(2-ethylhexyl) AdipateDinosebEthylene DibromideHexachlorobenzeneHfpo-DaHeptachlorHeptachlor EpoxideLassoMercuryMethoxychlorNetfosaaNfdhaNmefosaaOxamylPFBSPfdaPfdoaPfeesaPfhpaPfhpsPFHXSPfmbaPfmpaPFNAPFOAPFOSPfpesPftaPftrdaPfunaPentachlorophenolPicloramStyreneTetrachloroethyleneThallium, TotalToxapheneTrichloroethyleneVinyl Chloridecis-1,2-DichloroethyleneO-DichlorobenzeneP-Dichlorobenzenetrans-1,2-Dichloroethylene
Utility contact
Frequently asked questions about City of Houston
Is City of Houston tap water safe to drink?
EPA monitoring detected 42 contaminants in City of Houston's water. A detection isn't the same as a violation — most levels are within federal limits. See each level and source above, and the utility's annual Consumer Confidence Report for its official compliance status.
What contaminants were detected in City of Houston's water?
EPA monitoring detected Bromodichloromethane, Chloroform, Nitrate, Dibromochloromethane, TTHM, and others. The full list with the level and data source for each is above.
How many people does City of Houston serve?
City of Houston reports serving 2,970,543 people in Texas, per its EPA record.
Has City of Houston had any water quality violations?
The EPA has 26 violations on file for City of Houston, of which 14 are health-based (a contaminant limit or required treatment was breached) and 0 remain open. The rest are monitoring or reporting failures.
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.