Tap Water Quality Report
Tap water quality in Houston, Texas
Tap water in Houston, Texas receives a grade of D (64/100) from TapWaterSafety.org. It's served by 3 public water systems, primarily CITY OF HOUSTON UD 5 - KINGWOOD. The most significant water quality concerns are: Arsenic significantly above health guideline; Haloacetic acids (HAA9) significantly above health guideline; Chromium (hexavalent) significantly above health guideline; Bromochloroacetic acid significantly above health guideline; PFAS contamination. Data sources: EPA SDWIS, EPA ECHO, EWG Tap Water Database.
What's in Houston's tap water
Top water quality concerns identified by the EPA and Environmental Working Group across the utilities serving Houston.
Arsenic significantly above health guideline
Moderate concernArsenic detected at 1.1 ppb, 275x above the EWG health guideline of 0.004 ppb.
Haloacetic acids (HAA9) significantly above health guideline
Moderate concernHaloacetic acids (HAA9) detected at 1.93 ppb, 32x above the EWG health guideline of 0.06 ppb.
Chromium (hexavalent) significantly above health guideline
Moderate concernChromium (hexavalent) detected at 0.223 ppb, 11x above the EWG health guideline of 0.02 ppb.
Bromochloroacetic acid significantly above health guideline
Moderate concernBromochloroacetic acid detected at 4.57 ppb, 229x above the EWG health guideline of 0.02 ppb.
PFAS contamination
Severe concernPerfluorooctane sulfonate (PFOS), Perfluorooctanoic acid (PFOA) detected. PFAS are persistent chemicals linked to cancer and immune effects with no known safe exposure threshold.
EPA compliance record
Official U.S. EPA records for CITY OF HOUSTON UD 5 - KINGWOOD (system ID TX1010348) for the last 3 years. Checked 2026-10-07.
Source: U.S. EPA Enforcement and Compliance History Online (ECHO), from the Safe Drinking Water Information System. See EPA's full report.
Water systems serving Houston
Houston is served by 3 public water systems. Click any utility to see its complete grade card and treatment plant contact info.
CITY OF HOUSTON UD 5 - KINGWOOD
- Arsenic significantly above health guideline
- Haloacetic acids (HAA9) significantly above health guideline
- Chromium (hexavalent) significantly above health guideline
CITY OF HOUSTON
- Haloacetic acids (HAA9) significantly above health guideline
- Arsenic significantly above health guideline
- Bromochloroacetic acid significantly above health guideline
CLEAR LAKE CITY WATER AUTHORITY
- PFAS contamination
- Perfluorohexane sulfonate (PFHXS) significantly above health guideline
- Haloacetic acids (HAA9) significantly above health guideline
Recommended filters for Houston
Filters matched to the specific contaminants in Houston's water supply.
Reverse osmosis certified for arsenic (NSF/ANSI 58)
$429-$599Reverse osmosis certified under NSF/ANSI 58 for arsenic is the most reliable home option.
Carbon filter certified for VOCs (NSF/ANSI 53)
$180-$599Activated carbon is effective for disinfection byproducts. Look for NSF/ANSI 53 VOC reduction.
Disclosure: TapWaterSafety earns a commission from purchases made through these links. This does not influence our scoring methodology or filter selection.
All contaminants detected in Houston's tap water
Every contaminant identified, compared side-by-side against US EPA legal limits, the EU Drinking Water Directive (2020/2184), WHO Guidelines, and California's Public Health Goal. Why we show multiple standards →
| Contaminant | Detected | EWG US health-based |
EPA US legal |
EU DWD Europe |
WHO global |
CA PHG strictest US |
Tested sample year |
Status |
|---|---|---|---|---|---|---|---|---|
| Perfluorohexane sulfonate (PFHXS) PFAS |
3.04 ppt | 0.001 | 10.0 | — | — | — | — | 3039× over |
| Haloacetic acids (HAA9) Disinfection byproduct |
49.6 ppb | 0.06 | — | — | — | — | — | 827× over |
| Arsenic Heavy metal |
2.06 ppb | 0.004 | 10.0 | 10 | 10 | 0.004 | — | 516× over |
| Bromochloroacetic acid Disinfection byproduct |
5.75 ppb | 0.02 | — | — | — | — | — | 287× over |
| Haloacetic acids (HAA5) Disinfection byproduct |
26.0 ppb | 0.1 | 60.0 | 60 | — | — | — | 260× over |
| Total trihalomethanes (TTHMs) Disinfection byproduct |
35.9 ppb | 0.15 | 80.0 | 100 | — | — | — | 239× over |
| Bromodichloromethane Disinfection byproduct |
10.0 ppb | 0.06 | — | — | — | — | — | 167× over |
| Dichloroacetic acid Disinfection byproduct |
17.4 ppb | 0.2 | — | — | — | — | — | 87× over |
| Trichloroacetic acid Disinfection byproduct |
6.47 ppb | 0.1 | — | — | — | — | — | 65× over |
| Chloroform Disinfection byproduct |
20.7 ppb | 0.4 | — | — | — | — | — | 52× over |
| Dibromoacetic acid Disinfection byproduct |
1.52 ppb | 0.03 | — | — | — | — | — | 51× over |
| Chromium (hexavalent) Heavy metal |
0.747 ppb | 0.02 | — | — | — | — | — | 37× over |
| Dibromochloromethane Disinfection byproduct |
3.38 ppb | 0.1 | — | — | — | — | — | 34× over |
| Radium, combined (-226 and -228) Radiological |
0.85 pCi/L | 0.05 | 5.0 | — | — | — | — | 17× over |
| Perfluorooctane sulfonate (PFOS) PFAS |
3.79 ppt | 0.3 | 4.0 | 100 | 100 | 1 | — | 13× over |
| Uranium Radiological |
2.19 pCi/L | 0.43 | 20.0 | 30 | 30 | 0.43 | — | 5.1× over |
| Nitrate Inorganic |
0.387 ppm | 0.14 | 10.0 | 11.3 | 11.3 | 10 | — | 2.8× over |
| Perfluorooctanoic acid (PFOA) PFAS |
0.222 ppt | 0.09 | 4.0 | 100 | 100 | 0.007 | — | 2.5× over |
| 6:2 Fluorotelomer Sulfonic Acid (6:2 FTSA) Other |
1.69 ppt | 1.0 | — | — | — | — | — | 1.7× over |
| Atrazine Pesticide/Herbicide |
0.122 ppb | 0.1 | 3.0 | 0.1 | 100 | 0.15 | — | Fails EU |
| Bromoform Disinfection byproduct |
0.397 ppb | 0.5 | — | — | — | — | — | Below guideline |
| Simazine Pesticide/Herbicide |
0.0754 ppb | 0.1 | 4.0 | — | — | — | — | Below guideline |
| Barium Heavy metal |
265.7 ppb | 700.0 | 2000.0 | — | 1300 | 2000 | — | Below guideline |
| Aluminum Heavy metal |
101.9 ppb | 600.0 | — | 200 | — | 600 | — | Below guideline |
| Manganese Heavy metal |
16.8 ppb | 100.0 | — | 50 | 80 | — | — | Below guideline |
| Chlorate Disinfection byproduct |
31.3 ppb | 210.0 | — | — | — | — | — | Below guideline |
| Bromochloromethane Other |
0.00674 ppb | 0.06 | — | — | — | — | — | Below guideline |
| Vanadium Other |
1.91 ppb | 21.0 | — | — | — | — | — | Below guideline |
| Molybdenum Other |
2.76 ppb | 40.0 | — | — | — | — | — | Below guideline |
| Thallium Heavy metal |
0.00483 ppb | 0.1 | 2.0 | — | — | — | — | Below guideline |
| Selenium Heavy metal |
1.28 ppb | 30.0 | 50.0 | 20 | 40 | 30 | — | Below guideline |
| Di(2-ethylhexyl) phthalate Semi-volatile organic compound |
0.123 ppb | 3.0 | 6.0 | — | — | — | — | Below guideline |
| 1,4-Dioxane Semi-volatile organic compound |
0.00599 ppb | 0.35 | — | — | 50 | 1 | — | Below guideline |
| Monochloroacetic acid Disinfection byproduct |
0.573 ppb | 53.0 | — | — | — | — | — | Below guideline |
| Perfluorobutanoic Acid (PFBA) PFAS |
7.16 ppt | 1000.0 | — | — | — | — | — | Below guideline |
| Perfluorohexanoic Acid (PFHxA) PFAS |
5.83 ppt | 1000.0 | — | — | — | — | — | Below guideline |
| Perfluoropentanoic Acid (PFPeA) PFAS |
5.67 ppt | 1000.0 | — | — | — | — | — | Below guideline |
| Xylenes (total) Volatile organic compound |
2.99 ppb | 1800.0 | 10000.0 | — | — | — | — | Below guideline |
| Ethylbenzene Volatile organic compound |
0.453 ppb | 300.0 | 700.0 | 1 | 10 | 0.15 | — | Below guideline |
| Toluene Volatile organic compound |
0.224 ppb | 150.0 | 1000.0 | — | — | — | — | Below guideline |
| Perfluorobutane sulfonate (PFBS) PFAS |
2.68 ppt | 2000.0 | — | — | — | — | — | Below guideline |
| Perfluoroheptanoic acid (PFHPA) PFAS |
1.28 ppt | 1000.0 | — | — | — | — | — | Below guideline |
| Monobromoacetic acid Disinfection byproduct |
0.0292 ppb | 25.0 | — | — | — | — | — | Below guideline |
| Strontium Radiological |
0.361 ppb | 1500.0 | — | — | — | — | — | Below guideline |
| Cobalt Other |
0.0106 ppb | 70.0 | — | — | — | — | — | Below guideline |
| Picloram Other |
0.00476 ppb | 166.0 | 500.0 | — | — | — | — | Below guideline |
| 2-methyl-1-propene Other |
3.5 ppb | — | — | — | — | — | — | Below guideline |
| Cyanide Inorganic |
42.5 ppb | — | 200.0 | 50 | 70 | 150 | — | Below guideline |
| Erucylamide Other |
3.0 ppb | — | — | — | — | — | — | Below guideline |
| Fluoride Inorganic |
0.478 ppm | — | 4.0 | 1.5 | 1.5 | — | — | Below guideline |
| Germanium Other |
0.115 ppb | — | — | — | — | — | — | Below guideline |
| Hexadecanoic acid Other |
15.3 ppb | — | — | — | — | — | — | Below guideline |
| Lithium Other |
12.0 ppb | — | — | — | — | — | — | Below guideline |
| Methyl isobutyl ketone Other |
0.0777 ppb | — | — | — | — | — | — | Below guideline |
| o-toluidine Other |
0.0012 ppb | — | — | — | — | — | — | Below guideline |
| Octadecanoic acid Other |
32.8 ppb | — | — | — | — | — | — | Below guideline |
| Oleic acid Other |
3.2 ppb | — | — | — | — | — | — | Below guideline |
| Dalapon Pesticide/Herbicide |
0.012 ppb | — | 200.0 | — | — | — | — | Below guideline |
| 1-Butanol Other |
0.167 ppb | — | — | — | — | — | — | Below guideline |
All values in the unit of the detected level. Red cells indicate the detected level exceeds that standard. Some contaminants have limits in some jurisdictions but not others (shown as —). The "Tested" column shows the year each contaminant sample was collected.
Sources: US EPA, EU Drinking Water Directive 2020/2184, WHO Guidelines, California OEHHA PHGs, EWG Tap Water Database.
Treatment plant contact info
For service issues, water quality concerns, or to request a Consumer Confidence Report from CITY OF HOUSTON UD 5 - KINGWOOD.
General Contact
Treatment Plant
ZIP codes served
Houston's public water systems serve the following ZIP codes: