Water in Texas.
Texas spans every U.S. water profile — Edwards Aquifer in central Texas, Rio Grande surface water in the west, Houston ship channel industrial corridor in the southeast. Natural arsenic is widespread in groundwater across the state.
Houston's 2017 Hurricane Harvey flooding overwhelmed dozens of Superfund sites, mixing contaminated soil and water across the metro.
How Texas regulates drinking water.
Federal SDWA primacy. No state MCLs stricter than federal. Among the most permissive state environmental regimes in the country.
Texas Commission on Environmental Quality (TCEQ) — Public Drinking Water
Texas's water history, in order.
The contamination events, regulatory shifts, and major settlements that define how this state thinks about drinking water today.
- 2017
Hurricane Harvey floods 13 EPA Superfund sites in Houston metro; cross-contamination unprecedented.
- 2021
Statewide power-grid failure leaves millions without safe tap water for days; thousands of boil-water advisories.
- 2023
Texas-wide PFAS sampling under federal UCMR 5 identifies widespread detection.
The actual water you drink.
The physical rivers, aquifers, lakes, and reservoirs that feed Texas's public water systems. Source quality is the foundation of tap quality — and where the long-term protection fights happen.
- aquiferEdwards Aquifer
San Antonio + Central TX — among the largest karst aquifers in the world.
- riverTrinity River + Lakes Lewisville/Ray Hubbard
Dallas / Fort Worth metro.
- riverColorado River + Highland Lakes
Austin.
- riverRio Grande
El Paso, Lower Rio Grande Valley.
- aquiferOgallala Aquifer
Panhandle and West TX.
- aquiferCarrizo-Wilcox Aquifer
Central TX.
Source-water mix
~50% surface water, ~50% groundwater (varies by region)
Major cities served
Houston · San Antonio · Dallas · Austin · Fort Worth · El Paso
Who actually serves the water.
The largest public water systems in Texas by population served. Click your ZIP after to see the full live EWG report for your specific utility.
- Houston Public WorksHouston2,300Kserved
- San Antonio Water SystemSan Antonio1,900Kserved
- Dallas Water UtilitiesDallas metro2,600Kserved
- Austin WaterAustin1,000Kserved
- El Paso WaterEl Paso700Kserved
Where the contamination comes from.
Every state has a different industrial fingerprint. The industries below are the dominant historical and active contamination sources in Texas's drinking water systems.
Houston Ship Channel cumulative industrial exposure — among the most-contaminated industrial-residential overlap zones in the U.S. Oil and gas operations across multiple basins drive produced-water contamination. Military firefighting foam at Joint Base San Antonio and others.
What state data flags most consistently.
Drawn from EPA SDWIS sampling records, EWG state summaries, and regional regulatory action over the past five years. Read the full deep dive on each.
Arsenic
A naturally occurring carcinogen. Highest in private wells and the rural Southwest.
Trihalomethanes (TTHMs)
Byproducts of chlorinating water. Linked to bladder cancer at chronic exposure.
PFAS (Forever Chemicals)
A class of ~15,000 synthetic chemicals that don't break down. Now regulated for the first time.
Chromium-6 (Hexavalent Chromium)
The Erin Brockovich chemical. A known carcinogen with no federal-specific limit yet.
Nitrate
Fertilizer and animal waste runoff. Acutely dangerous for infants under 6 months.
Risk isn't evenly distributed.
Colonias residents along the Texas-Mexico border face among the worst infrastructure gaps in the U.S. Houston ship-channel-area residents face cumulative industrial exposure.
~14% on private wells, with significant rural West TX and Hill Country coverage gaps.
What's coming for Texas's water.
Megadrought reshapes Texas water supply across all major basins. Hurricane intensity (Harvey 2017, Beryl 2024) overwhelms treatment plants. Power-grid failure (Feb 2021) demonstrated water-system fragility. Aquifer drawdown accelerates Ogallala and Edwards.
Voluntary statewide
TCEQ provides voluntary screening; participation is uneven across the state's 1,000+ districts.
Five questions for your next Consumer Confidence Report.
Your utility is required to send you a Consumer Confidence Report annually. Most are dense and procedural. These are the questions worth following up on for Texas specifically.
- 1
Has my utility experienced any 2021 power-grid-related infrastructure damage that affects current operations?
- 2
What is my system's drought-trigger water-restriction stage?
- 3
If I'm in Houston ship channel area, has my water been impacted by Superfund site flooding?
- 4
Has my colonias-area system been part of federal infrastructure funding?
Most state regulators allow public records requests for the underlying lab reports behind your CCR — your utility should be able to provide them on request.
What's changed in Texas water law.
Drinking water regulation moves at the state level as much as the federal level. Below are notable recent bills and regulatory actions specific to Texas.
- 2023
HB 1565 — Statewide Water Plan update and Rural Water Supply Fund expansion.
NSF/ANSI 58 reverse osmosis is the most universal solution for Texas' diverse contaminant profile.
We don't recommend brands — the NSF/ANSI certification number matters more than the name on the box.
This is the state. Your address is the answer.
State-level patterns don't tell you about your specific tap. Run your ZIP for the live EWG contaminant report on your utility — or build a personalized Water File for your household.
Source-water mix, utility counts, lead-service-line estimates, and private-well shares are approximate, drawn from EPA SDWIS public data and state primacy-agency summaries. Contaminant rankings reflect EWG state-level monitoring data and regional regulatory action — they are not exhaustive. Timeline events are publicly documented. See methodology for the full sourcing. Search EPA SDWIS for Texas