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Arsenic in Drinking Water in Texas

What residents of Texas need to know about arsenic in drinking water — including natural geological sources, private well risk, which utilities have documented violations, and how to remove arsenic from tap water.

Source: EPA SDWIS, Texas Commission on Environmental Quality, USGS · Last reviewed: 2025-01-01

Quick Answer

Is arsenic in drinking water a concern in Texas?

Yes. Texas has significant arsenic occurrence, particularly in the Ogallala Aquifer of the Texas Panhandle and High Plains, in the volcanic geology of far West Texas (Trans-Pecos region), and in Gulf Coastal Plain aquifer systems in parts of South Texas. Texas has had more public water systems exceed the arsenic MCL than most other states, reflecting both the state's large size and its reliance on groundwater from diverse geological settings.

Where does arsenic come from in Texas's water?

Three primary pathways exist in Texas: (1) Ogallala Aquifer in the Panhandle and South Plains (Lubbock area) with naturally occurring arsenic from Great Plains sedimentary geology, (2) Volcanic and hydrothermal geology in the Trans-Pecos region (Far West Texas), and (3) Gulf Coastal Plain aquifer systems in South Texas where reducing geochemical conditions can mobilize arsenic. Private wells and small water systems across these regions face elevated risk.

What should Texas residents know?

Texas Panhandle communities on the Ogallala, Far West Texas communities in the Trans-Pecos, and South Texas communities on Gulf Coastal Plain aquifers face the highest documented risk. TCEQ has documented dozens of Texas public water systems requiring arsenic treatment and has worked with small communities on compliance. Private well owners across these regions have no regulatory protection.

Key Facts

EPA MCL10 µg/L (10 ppb)
MCLGZero
Primary sourceOgallala Aquifer (Panhandle/South Plains); Trans-Pecos volcanic geology; Gulf Coastal Plain (South Texas)
Compliance historyOne of the states with most PWS arsenic exceedances — large size and diverse geology
Environmental justiceSouth Texas border colonias — economically disadvantaged communities with arsenic compliance challenges
State regulatorTexas Commission on Environmental Quality (TCEQ)
Health effectsBladder, lung, skin cancer; cardiovascular; diabetes risk
Effective treatmentActivated alumina or reverse osmosis — both widely deployed at TX community water systems

Why Arsenic Matters in Texas

Texas's size and geological diversity make arsenic a statewide concern with multiple distinct hotspot areas. The Panhandle and South Plains region — dependent entirely on the declining Ogallala Aquifer — has documented arsenic across a broad area. Trans-Pecos Texas, with its volcanic mountains and desert basins, has some of the highest naturally occurring arsenic concentrations in the state. South Texas border communities, many of which are economically disadvantaged, have faced arsenic compliance challenges in both public water systems and private wells (colonias). TCEQ has provided compliance assistance and has sought state and federal funding for treatment in disadvantaged communities.

Texas Arsenic Program

moderate geologic risk

Texas TCEQ monitors arsenic under federal SDWIS and has documented elevated arsenic in the western Trans-Pecos and Big Bend regions, where volcanic geology and arid conditions concentrate arsenic in groundwater. Numerous small Texas water systems in the Permian Basin and Trans-Pecos required treatment after the 2006 MCL change. Private well owners in west Texas face elevated arsenic risk compared to the state's eastern half.

Texas Utilities With Arsenic Violation Records

The utilities listed below have at least one arsenic violation on record in EPA's SDWIS database. Violations may be open or resolved — see individual utility pages for current status and risk level.

How Does Arsenic Get Into Drinking Water?

Arsenic in drinking water is almost always naturally occurring — it leaches from arsenic-bearing rocks and minerals into groundwater over time. New England granite, Southwest volcanic geology, and Upper Midwest glacial aquifers are the primary high-risk formations. It has no taste, odor, or color.

Full arsenic overview — geology maps, health effects, all 50 states

Who Should Pay Closest Attention

Texas Panhandle communities (Amarillo area, Lubbock South Plains), Trans-Pecos communities (El Paso, Midland-Odessa area, Alpine/Marfa, Presidio), South Texas border communities and colonias, and rural private well owners in arsenic-bearing geological formations throughout the state face elevated risk.

Private well owners near mining districts or agricultural areas

Residents in states with documented volcanic or geothermal geology

Long-term consumers of water from small groundwater systems

Households in homes built before 1960 with older well casings

Residents whose well water has never been tested for arsenic

Anyone living in a state where bedrock wells are common

How to Check Your Situation in Texas

  1. 1

    Identify your water source. If you use a public utility, use the ZIP lookup on this page to find your system and check its compliance record.

  2. 2

    If on public water, review your utility's most recent Consumer Confidence Report (CCR) for arsenic monitoring data. The MCL is 10 ppb — your report should show recent test results.

  3. 3

    If on a private well, order an arsenic test from a Texas Commission on Environmental Quality-certified laboratory. A basic arsenic test costs $15–$40. The state agency website maintains a certified lab list.

  4. 4

    Test your well at the tap — not just at the wellhead. The entire water distribution system within your home can affect water quality.

  5. 5

    If your test shows arsenic above 5 ppb, install certified treatment immediately. If above 10 ppb, do not use the water for drinking or cooking until treatment is installed.

  6. 6

    Retest after installing treatment to confirm it is working as certified. Replace filter media on the manufacturer's schedule — an exhausted filter may not perform as rated.

Treatment Options for Arsenic

Boiling does not remove arsenic — it concentrates it. Standard activated carbon filters (Brita, etc.) do not effectively remove arsenic. Certified treatment is required.

NSF/ANSI Standard 58 — Reverse Osmosis

RO systems certified to NSF/ANSI 58 remove 85–95% of arsenic. Under-sink installation. Most effective for removing multiple contaminants simultaneously. Replace membranes and pre-filters on schedule.

Activated Alumina Filters

Activated alumina is specifically designed for arsenic and fluoride removal. Point-of-use or whole-house options available. Must be certified by NSF International or WQA for arsenic reduction. Requires periodic media regeneration or replacement.

Iron/Manganese Oxidation Filters

Effective for arsenic in iron-rich well water, which is common in the Midwest and New England. Oxidation converts dissolved iron and arsenic to a form that can be filtered out. Best when arsenic is co-occurring with high iron levels.

What does NOT work for arsenic

Standard activated carbon filters (Brita, refrigerator filters, most pitcher filters) do NOT effectively remove arsenic. Boiling concentrates arsenic. Water softeners do not remove arsenic. Only use products with NSF certification specifically for arsenic reduction.

See: Reverse Osmosis guide · Activated carbon filter guide

Take Action Now

1

If you use a private well in Texas, test for arsenic — especially if you are in a region with granite, volcanic, or sedimentary geology. A basic arsenic test costs $15–$40 at a state-certified lab.

2

Public water users: check your utility's Consumer Confidence Report (CCR) for arsenic results. The EPA MCL is 10 ppb — any detection warrants attention.

3

If arsenic is detected above 10 ppb (or even below it, given MCLG is zero), install an NSF/ANSI 58-certified reverse osmosis system for drinking and cooking water.

4

Standard carbon filters do NOT remove arsenic — do not rely on a Brita or refrigerator filter for arsenic protection.

Frequently Asked Questions

Related Pages

Data Sources & Provenance

All data on this page is sourced from official U.S. government or public datasets.

EPA — Arsenic in Drinking WaterView source
USGS — Arsenic in GroundwaterView source
CDC — Arsenic and HealthView source
EPA SDWIS — Violation and Compliance DataView source
USGS — Occurrence of Arsenic in US GroundwaterView source
Last updated: 2025-01-01
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