Houston
TX

Is Houston, TX Tap Water Safe to Drink?

Houston, TX tap water has a qualified safety picture. It meets federal limits for PFAS under current EPA rules, but lithium has been detected above a recommended EPA health benchmark in water serving most of the area, and several PFAS compounds have been found at measurable levels. Most people can drink it without immediate concern, but households with infants or pregnant individuals may want to consider additional filtration.

231Water systems
107ZIP codes
100%ZIPs above EPA guideline
Metro areaHouston-Pasadena-The Woodlands, TX
Latest data2025-11-18

Where Does Houston Get Its Water?

Houston, TX draws its drinking water from a large and fragmented network of utilities. The region is served by more than 200 separate public water systems, ranging from the main City of Houston system to dozens of Municipal Utility Districts, Water Control and Improvement Districts, and smaller special-purpose districts spread across Harris County and parts of Fort Bend and Montgomery Counties.

The City of Houston operates several surface water treatment facilities, including major plants that process water from regional surface sources. Many of the surrounding utility districts rely on groundwater from local aquifers, while others purchase treated surface water from the city or regional authorities and distribute it to their customers.

Smaller systems throughout the greater Houston area, including districts serving communities like Kingwood, Clear Lake, Jersey Village, and Pasadena, each maintain their own water sources and treatment infrastructure. This patchwork structure means the source and treatment approach can vary meaningfully depending on which utility serves your address.

How Is Houston Tap Water Treated?

Treatment across Houston-area utilities varies by system but commonly includes coagulation and sedimentation for surface water supplies, along with filtration to remove particulates. Several utilities use granular activated carbon to reduce organic compounds and certain contaminants. Membrane filtration is also used by some systems, providing an additional barrier against a range of substances.

Disinfection methods across the region include free chlorine, chloramine, and in some cases ozone. Chlorine and chloramines are the most common final disinfectants, and they remain active in the distribution system to prevent bacterial regrowth between the treatment plant and your tap. A small residual of disinfectant in your water is intentional and normal.

Some utilities also use ion exchange and aeration as part of their treatment processes, particularly for groundwater sources where naturally occurring minerals may be elevated. The specific treatment train at your address depends on which utility district supplies your home, so checking your annual Consumer Confidence Report from your local system will give you the most precise picture.

What's in Houston Tap Water?

The most notable finding in recent EPA testing is lithium. The highest measured concentration across Houston-area systems reached 79.6 micrograms per liter, well above an EPA health benchmark of 10 micrograms per liter. Lithium detections were logged across 213 ZIP codes in the dataset, and levels above the benchmark were found in 106 of those ZIP codes.

Several PFAS compounds were also detected. PFTrDA, a long-chain PFAS, was found at a peak of 0.007 micrograms per liter, which is at the EPA's current reference level for that compound. PFBA, 8:2 FTS, and 6:2 FTS were each detected but their measured values did not exceed any current EPA guideline.

Lithium in drinking water typically originates from natural geological sources in the ground. PFAS compounds, often called forever chemicals, generally enter water supplies through industrial activity, firefighting foam use, or consumer product runoff. The presence of both in Houston-area water reflects patterns seen across much of Texas and the broader southern United States.

ContaminantPeak detectedEPA guidelineZIPs detectedStatus
lithium 79.6 µg/L 10 µg/L 106 ZIPs Above guideline
PFTrDA 0.007 µg/L 0.007 µg/L 1 ZIP Above guideline
PFBA 0.0072 µg/L — 6 ZIPs Within guideline
8:2 FTS 0.005 µg/L — 0 ZIPs Within guideline
6:2 FTS 0.005 µg/L — 0 ZIPs Within guideline

Health Risk Profile for Houston

Lithium is the primary concern here. The EPA has identified 10 micrograms per liter as a health benchmark for lithium in drinking water, and the peak detected value across Houston-area systems was 79.6 micrograms per liter. This benchmark is a health reference point rather than an enforceable federal maximum, meaning utilities are not currently required by law to reduce lithium below this level. Still, ongoing exposure above the benchmark warrants attention.

Infants, pregnant individuals, and people with certain thyroid or kidney conditions may be more sensitive to lithium in drinking water. For these groups, even moderate exposure above the benchmark level could carry a higher risk, and consulting a physician about filtration or alternative water sources is a reasonable step.

For filtering lithium and PFAS, look for a pitcher or under-sink filter certified to NSF/ANSI standards. NSF/ANSI is an independent third-party certification that confirms a filter performs as advertised. For PFAS, seek NSF/ANSI 58 certification (reverse osmosis) or NSF/ANSI P473 certification. For lithium, reverse osmosis systems certified to NSF/ANSI 58 are the most effective option currently available for home use.

The science on low-level lithium exposure from drinking water is still developing. Some research suggests potential neurological effects at elevated concentrations, but regulatory limits have not yet been finalized. For PFAS, the EPA issued enforceable limits for PFOA and PFOS in 2024, but the compounds detected in Houston-area water, including PFBA, 8:2 FTS, and 6:2 FTS, do not yet have enforceable federal maximums.

Best Broad-Spectrum Filters for This Water Profile

This city profile includes PFAS detections, chlorine disinfection, and other dissolved contaminants. Reverse osmosis (RO) systems certified under NSF/ANSI 58 provide broad reduction coverage; for PFAS specifically, confirm NSF/ANSI P473 or equivalent PFAS reduction certification.

Waterdrop G3P600 Reverse Osmosis System
Under-sink RO system

8-stage tankless RO system certified to NSF/ANSI 58, reduces 1,000+ contaminants including PFAS, lead, arsenic, fluoride, and nitrates.

See recommendations matched to your exact address: choose your ZIP code below.

Frequently Asked Questions about Houston Tap Water

Is Houston tap water safe to drink?

Houston tap water generally meets current federal drinking water standards. The main concern is lithium, detected at levels above an EPA health benchmark in much of the service area, and the presence of several PFAS compounds. For most healthy adults, short-term consumption poses limited immediate risk, but households with infants or pregnant individuals should consider a reverse osmosis filter.

What contaminants are in Houston tap water?

Recent EPA testing found lithium at a peak of 79.6 micrograms per liter, above the EPA health benchmark of 10 micrograms per liter. PFTrDA was detected at 0.007 micrograms per liter, at the EPA reference level. PFBA, 8:2 FTS, and 6:2 FTS were also detected but did not exceed any current EPA guideline. Chlorine and chloramines are present as intentional disinfectants.

Where does Houston get its drinking water?

Houston's water comes from a mix of surface water and groundwater sources managed by more than 200 separate utility systems. The City of Houston treats surface water at large municipal plants. Many surrounding Municipal Utility Districts and Water Control Districts draw from local aquifers or purchase treated water from the city and distribute it to residential customers across Harris, Fort Bend, and Montgomery Counties.

Do I need a water filter in Houston?

Given the lithium and PFAS detections in Houston-area water, a filter is worth considering, especially for households with infants, pregnant individuals, or people with thyroid or kidney conditions. A reverse osmosis system certified to NSF/ANSI 58 is the most effective home option for reducing both lithium and PFAS. For PFAS specifically, also look for NSF/ANSI P473 certification on the product label.

How often is Houston tap water tested?

Houston-area utilities are required to test their water regularly under federal EPA rules, with frequency depending on the contaminant and system size. The data on this page comes from recent EPA monitoring that includes testing conducted through late 2025. Each utility also publishes an annual Consumer Confidence Report with its own results. You can request that report directly from your local water district.

What is the best water filter for Houston?

For Houston's combination of lithium and PFAS concerns, a reverse osmosis system certified to NSF/ANSI 58 is the strongest home option. Reverse osmosis removes a broad range of dissolved contaminants including lithium and most PFAS compounds. If you also want added protection for PFAS specifically, choose a product that carries NSF/ANSI P473 certification. Pitcher filters with granular activated carbon can reduce chlorine taste but are less effective against lithium.

Tap water reports by ZIP in Houston

Water utilities serving Houston, TX

Service area boundaries are approximate and based on state filings or modeled estimates. Contact your utility to confirm exact service at a specific address.

Modeled boundaries are shown with a dashed outline.

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