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Well Water in Texas

Contaminant risks, testing requirements, and treatment recommendations for private well owners in Texas.

Texas Geology and Groundwater

Texas sits on Gulf Coast, Edwards, and Ogallala aquifers. This geology directly determines what contaminants are likely in private well water. Moderate risk exists for arsenic, nitrate, PFAS, uranium.

Contaminant Risk Profile

ContaminantRisk LevelWhy
ArsenicModerate riskSome geological zones have elevated levels. Test recommended.
NitrateModerate riskSome areas near farmland or septic systems may have elevated levels.
RadonLow riskNot a primary concern in most of this state.
PFASModerate riskSome known contamination sites exist. Check EWG's PFAS map for your area.
Iron/ManganeseModerate riskFound in some wells depending on local geology.
UraniumModerate riskSome geological zones may have elevated levels.
FluorideModerate riskSome wells may have naturally elevated levels.

How Texas Compares: Municipal Water Data

CheckMyTap tracks water quality for 76 cities in Texas. While these numbers reflect municipal water (not private wells), they indicate the baseline mineral content of Texas's water sources. Private wells often draw from the same aquifers but with less treatment.

MetricTexas AverageNational Average
Hardness189 PPM (very hard)170 PPM
Hardness range67 - 298 PPM25 - 400+ PPM
Lead (avg municipal)2 ppb3.2 ppb
Nitrate (avg municipal)0.5 mg/L1.1 mg/L
Cities with PFAS detected70 of 76~45% nationally
Cities exceeding PFAS MCL (4 ppt)70

Hardest water in Texas: San Angelo (298 PPM), McAllen (290 PPM), Abilene (290 PPM), New Braunfels (285 PPM), Lubbock (284 PPM).

Testing Requirements in Texas

Texas does not have a statewide mandatory testing requirement for existing private wells. Regardless of state requirements, the EPA recommends testing annually for:

  • Every year: Total coliform bacteria, E. coli, nitrate, pH, and total dissolved solids
  • At least once: Arsenic, lead, copper, fluoride, and any contaminant identified as a local risk
  • Recommended for Texas: PFAS panel, especially if near military bases or industrial sites
  • Recommended for Texas: Uranium, especially in areas with granitic or metamorphic bedrock
  • After events: Retest after flooding, well repairs, nearby construction, or any change in taste/color/odor

Recommended Treatment for Texas Wells

Based on Texas's geology and common contaminant risks, these treatment systems address the most likely issues:

Reverse Osmosis

Removes arsenic, uranium, and most dissolved contaminants from drinking water

Learn more
Water Softener

Texas groundwater averages 189 PPM. A softener prevents scale damage, reduces energy waste, and extends appliance life

Learn more
UV Disinfection

Kills bacteria and viruses without chemicals. Recommended for all well water systems

Already have your lab results? Use our free well water interpreter to find out what your numbers mean. Interpret your well water lab report

Frequently Asked Questions

Is well water in Texas safe to drink?

Well water quality in Texas varies significantly by location and geology. Texas sits on Gulf Coast, Edwards, and Ogallala aquifers. No single contaminant dominates statewide, but local conditions vary. The only way to know your specific water quality is to test it. Use our free interpreter to understand your results.

How often should I test my well water in Texas?

The EPA recommends testing annually for bacteria (total coliform, E. coli), nitrate, total dissolved solids, and pH. Given Texas's arsenic risk, test for arsenic at least once and after any changes to your well. Test more frequently if you notice changes in taste, color, or odor, or after flooding, nearby construction, or well repairs.

Does Texas require well water testing?

Texas does not have a statewide mandatory testing requirement for existing private wells. However, the EPA strongly recommends annual testing regardless of state requirements. Your county health department may have additional local requirements.

What is the average water hardness in Texas?

Municipal water in Texas averages 189 PPM across 76 cities tracked by CheckMyTap, ranging from 67 to 298 PPM. Private well water typically runs 20-50% harder than city water because groundwater has more contact time with mineral formations. Most Texas well owners benefit from a water softener. Check your city's data.

View All 76 Texas City Reports