What was found in ZIP 77070
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 |
|---|---|---|---|
| Fluoride | 140 µg/L 3.5% of the EPA limit 4000 µg/L Main supplier: CITY OF HOUSTON WILLOW CHASE · 14,169 people · 2018
Highest in the ZIP: 2740 µg/L — HARRIS COUNTY WCID 119 · 9,150 people · 2018 | 12/12 | SYR4 |
| Nitrate | 259.49999999999994 µg/L 2.6% of the EPA limit 10000 µg/L Main supplier: CITY OF HOUSTON WILLOW CHASE · 14,169 people · 2019
Highest in the ZIP: 1840 µg/L — HARRIS COUNTY MUD 468 · 7,944 people · 2019 | 12/12 | SYR4 |
| Nitrate-Nitrite | 237.5 µg/L 2.4% of the EPA limit 10000 µg/L Main supplier: CITY OF HOUSTON WILLOW CHASE · 14,169 people · 2015
Highest in the ZIP: 1725.9999999999998 µg/L — HARRIS COUNTY MUD 468 · 7,944 people · 2015 | 12/12 | SYR4 |
| Copper | 198.79999999999998 µg/L 15% of the EPA limit 1300 µg/L Main supplier: CITY OF HOUSTON WILLOW CHASE · 14,169 people · 2017
Highest in the ZIP: 488.14999999999964 µg/L — HARRIS COUNTY MUD 230 · 10,404 people · 2019 | 12/12 | SYR4 |
| Barium | 280.65 µg/L 14% of the EPA limit 2000 µg/L Main supplier: CITY OF HOUSTON WILLOW CHASE · 14,169 people · 2019
Highest in the ZIP: 403.2 µg/L — HARRIS COUNTY MUD 18 HEATHERWOOD HUNTERS · 4,083 people · 2019 | 12/12 | SYR4 |
| Cyanide | 124.5 µg/L 62% of the EPA limit 200 µg/L Highest in the ZIP: CHARTERWOOD MUD · 5,832 people · 2017 | 5/12 | SYR4 |
| Lithium | 14 µg/L No EPA limit set Main supplier: CITY OF HOUSTON WILLOW CHASE · 14,169 people · 2025
Highest in the ZIP: 67.5 µg/L — HARRIS COUNTY WCID 119 · 9,150 people · 2023 | 6/12 | UCMR-5 |
| Nitrite | 57 µg/L 5.7% of the EPA limit 1000 µg/L Highest in the ZIP: HARRIS COUNTY MUD 18 HEATHERWOOD HUNTERS · 4,083 people · 2015 | 7/12 | SYR4 |
| TTHM | 11.754999999999995 µg/L 15% of the EPA limit 80 µg/L Main supplier: CITY OF HOUSTON WILLOW CHASE · 14,169 people · 2019
Highest in the ZIP: 47.24999999999998 µg/L — HARRIS COUNTY WCID 119 · 9,150 people · 2019 | 11/12 | SYR4 |
| Bromoform | 7.025 µg/L No EPA limit set Main supplier: CITY OF HOUSTON WILLOW CHASE · 14,169 people · 2019
Highest in the ZIP: 35.5 µg/L — MILLS ROAD MUD · 6,717 people · 2019 | 9/12 | SYR4 |
| Total Haloacetic Acids (HAA5) | 23.725 µg/L 40% of the EPA limit 60 µg/L Main supplier: CITY OF HOUSTON WILLOW CHASE · 14,169 people · 2019
Highest in the ZIP: 33.7 µg/L — HARRIS COUNTY MUD 468 · 7,944 people · 2019 | 10/12 | SYR4 |
| Lead | 3.4049999999999914 µg/L 23% of the EPA limit 15 µg/L Main supplier: CITY OF HOUSTON WILLOW CHASE · 14,169 people · 2017
Highest in the ZIP: 30.12 µg/L — CYPRESS FOREST PUD · 3,912 people · 2019 | 12/12 | SYR4 |
| Dibromochloromethane | 5.339999999999992 µg/L No EPA limit set Main supplier: CITY OF HOUSTON WILLOW CHASE · 14,169 people · 2019
Highest in the ZIP: 27.359999999999992 µg/L — HARRIS COUNTY WCID 119 · 9,150 people · 2019 | 11/12 | SYR4 |
| Dichloroacetic Acid | 17.244999999999997 µg/L No EPA limit set Main supplier: CITY OF HOUSTON WILLOW CHASE · 14,169 people · 2019
Highest in the ZIP: 26.2 µg/L — HARRIS COUNTY MUD 468 · 7,944 people · 2019 | 9/12 | SYR4 |
| Chloroform | 3.035 µg/L No EPA limit set Main supplier: CITY OF HOUSTON WILLOW CHASE · 14,169 people · 2019
Highest in the ZIP: 25.65999999999999 µg/L — CHARTERWOOD MUD · 5,832 people · 2019 | 11/12 | SYR4 |
| Combined Uranium | 5.32 µg/L 18% of the EPA limit 30 µg/L Main supplier: CITY OF HOUSTON WILLOW CHASE · 14,169 people · 2018
Highest in the ZIP: 17.99 µg/L — EMERALD FOREST UTILITY DISTRICT · 7,326 people · 2017 | 6/12 | SYR4 |
| Selenium | 6.865 µg/L 14% of the EPA limit 50 µg/L Main supplier: CITY OF HOUSTON WILLOW CHASE · 14,169 people · 2019
Highest in the ZIP: 13.6 µg/L — HARRIS COUNTY MUD 230 · 10,404 people · 2019 | 6/12 | SYR4 |
| Xylenes, Total | 3.355 µg/L 0% of the EPA limit 10000 µg/L Main supplier: CITY OF HOUSTON WILLOW CHASE · 14,169 people · 2019
Highest in the ZIP: 12.919999999999998 µg/L — HARRIS COUNTY MUD 18 HEATHERWOOD HUNTERS · 4,083 people · 2019 | 4/12 | SYR4 |
| Gross Alpha, Excl. Radon And U | 4 pCi/L 27% of the EPA limit 15 pCi/L Main supplier: CITY OF HOUSTON WILLOW CHASE · 14,169 people · 2018
Highest in the ZIP: 12.9 pCi/L — EMERALD FOREST UTILITY DISTRICT · 7,326 people · 2017 | 6/12 | SYR4 |
| Gross Beta Particle Activity | 4.495 pCi/L No EPA limit set Main supplier: CITY OF HOUSTON WILLOW CHASE · 14,169 people · 2018
Highest in the ZIP: 10.08 pCi/L — EMERALD FOREST UTILITY DISTRICT · 7,326 people · 2017 | 6/12 | SYR4 |
| Arsenic | 3.3749999999999996 µg/L 34% of the EPA limit 10 µg/L Main supplier: CITY OF HOUSTON WILLOW CHASE · 14,169 people · 2019
Highest in the ZIP: 9.850000000000001 µg/L — PRESTONWOOD FOREST UTILITY DISTRICT · 5,940 people · 2019 | 10/12 | SYR4 |
| Bromodichloromethane | 4.92 µg/L No EPA limit set Main supplier: CITY OF HOUSTON WILLOW CHASE · 14,169 people · 2019
Highest in the ZIP: 9.689999999999992 µg/L — HARRIS COUNTY WCID 119 · 9,150 people · 2019 | 11/12 | SYR4 |
| Dibromoacetic Acid | 3.6500000000000004 µg/L No EPA limit set Main supplier: CITY OF HOUSTON WILLOW CHASE · 14,169 people · 2019
Highest in the ZIP: 7.52 µg/L — HARRIS COUNTY WCID 119 · 9,150 people · 2019 | 7/12 | SYR4 |
| Monochloroacetic Acid | 6.879999999999998 µg/L No EPA limit set Highest in the ZIP: CHARTERWOOD MUD · 5,832 people · 2019 | 8/12 | SYR4 |
| Trichloroacetic Acid | 5.199999999999999 µg/L No EPA limit set Main supplier: CITY OF HOUSTON WILLOW CHASE · 14,169 people · 2019
Highest in the ZIP: 6.1 µg/L — HARRIS COUNTY MUD 468 · 7,944 people · 2019 | 8/12 | SYR4 |
| Di(2-ethylhexyl) Phthalate | 0.7200 µg/L 12% of the EPA limit 6 µg/L Main supplier: CITY OF HOUSTON WILLOW CHASE · 14,169 people · 2019
Highest in the ZIP: 3 µg/L — HARRIS COUNTY WCID 119 · 9,150 people · 2019 | 5/12 | SYR4 |
| Combined Radium (-226 And -228) | 2.98 pCi/L 60% of the EPA limit 5 pCi/L Highest in the ZIP: EMERALD FOREST UTILITY DISTRICT · 7,326 people · 2017 | 6/12 | SYR4 |
| Atrazine | 2 µg/L 67% of the EPA limit 3 µg/L Highest in the ZIP: HARRIS COUNTY MUD 18 HEATHERWOOD HUNTERS · 4,083 people · 2019 | 6/12 | SYR4 |
| Monobromoacetic Acid | 2 µg/L No EPA limit set Main supplier: CITY OF HOUSTON WILLOW CHASE · 14,169 people · 2019 | 2/12 | SYR4 |
| Toluene | 2 µg/L 0.2% of the EPA limit 1000 µg/L Highest in the ZIP: HARRIS COUNTY MUD 18 HEATHERWOOD HUNTERS · 4,083 people · 2019 | 1/12 | SYR4 |
| Ethylbenzene | 1.2 µg/L 0.2% of the EPA limit 700 µg/L Highest in the ZIP: HARRIS COUNTY MUD 18 HEATHERWOOD HUNTERS · 4,083 people · 2019 | 1/12 | SYR4 |
| Simazine | 0.2180 µg/L 5.5% of the EPA limit 4 µg/L Highest in the ZIP: HARRIS COUNTY WCID 119 · 9,150 people · 2019 | 5/12 | SYR4 |
| Pfpea | 0.0150 µg/L No EPA limit set Highest in the ZIP: HARRIS COUNTY MUD 230 · 10,404 people · 2023 | 10/12 | UCMR-5 |
| Lead | 0.0 mg/L 0% of the EPA limit 0.0150 mg/L Main supplier: CITY OF HOUSTON WILLOW CHASE · 14,169 people · 2023
Highest in the ZIP: 0.0127 mg/L — LAKE FOREST UTILITY DISTRICT · 7,106 people · 2025 | 12/12 | LCR |
| Pfhxa | 0.0087 µg/L No EPA limit set Highest in the ZIP: HARRIS COUNTY WCID 119 · 9,150 people · 2023 | 9/12 | UCMR-5 |
| Pfba | 0.0062 µg/L No EPA limit set Highest in the ZIP: MALCOMSON ROAD UTILITY DISTRICT · 7,231 people · 2025 | 7/12 | UCMR-5 |
| PFBS | 0.0043 µg/L No EPA limit set Highest in the ZIP: HARRIS COUNTY WCID 119 · 9,150 people · 2023 | 2/12 | 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 77070
| Supplier | State | Population served |
|---|---|---|
| CITY OF HOUSTON WILLOW CHASE | TX | 14,169 |
| HARRIS COUNTY MUD 230 | TX | 10,404 |
| HARRIS COUNTY WCID 119 | TX | 9,150 |
| HARRIS COUNTY MUD 468 | TX | 7,944 |
| EMERALD FOREST UTILITY DISTRICT | TX | 7,326 |
| MALCOMSON ROAD UTILITY DISTRICT | TX | 7,231 |
| LAKE FOREST UTILITY DISTRICT | TX | 7,106 |
| MILLS ROAD MUD | TX | 6,717 |
| PRESTONWOOD FOREST UTILITY DISTRICT | TX | 5,940 |
| CHARTERWOOD MUD | TX | 5,832 |
| HARRIS COUNTY MUD 18 HEATHERWOOD HUNTERS | TX | 4,083 |
| CYPRESS FOREST PUD | TX | 3,912 |
Frequently asked questions about ZIP 77070 tap water
Is the tap water in ZIP 77070 safe to drink?
EPA testing detected 37 contaminants across the water suppliers serving ZIP 77070. 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 77070?
12 public water suppliers report EPA drinking-water monitoring for ZIP 77070. Each is listed above with its population served.
What contaminants are in ZIP 77070's water?
EPA monitoring detected Fluoride, Nitrate, Nitrate-Nitrite, Copper, Barium, and others across this ZIP's suppliers. The full list with levels and sources is above.