Over 1.8 million Texas households depend on private wells[5]. Texas has no testing requirements for private wells — not at construction, not at sale, not ever[1].
That means many Texas well owners have never tested their water.
Quick Answer
Test for bacteriaColiform BacteriaA group of bacteria used as indicators of potential contamination. Total coliform presence suggests a pathway for pathogens to enter your well.EPA MCL: 0 (no coliform should be present)Learn more → (contamination indicators), nitratesNitratesCompounds that enter groundwater from fertilizers, septic systems, and animal waste. Especially dangerous for infants under 6 months (blue baby syndrome).EPA MCL: 10 mg/L (ppm)Learn more → (fertilizer compounds), hardnessHardness (Calcium Carbonate)The concentration of dissolved calcium and magnesium in water. Hard water causes scale buildup in pipes, water heaters, and fixtures.No EPA standard. Soft: <1 gpg. Moderate: 1-7 gpg. Hard: 7-10.5 gpg. Very Hard: >10.5 gpg.Learn more → (dissolved calcium), arsenicArsenicA toxic element found naturally in bedrock that dissolves into groundwater. Odorless and tasteless, making testing the only way to detect it.EPA MCL: 10 ppb (0.01 mg/L)Learn more → (toxic bedrock element), and TDSTDS (Total Dissolved Solids)The total amount of dissolved minerals, salts, and metals in water. A general indicator of water quality, though not all dissolved solids are harmful.EPA Secondary MCL: 500 mg/LLearn more → (total dissolved solids) at minimum. Texas has zero testing mandates — if you have not tested, do it now.
Common TX Well Water Issues
| Issue | Where in TX | Learn More |
|---|---|---|
| Extreme hardness | Central TX, Hill Country, Panhandle | Hard water guide |
| Arsenic | West TX, Panhandle, parts of South TX | Arsenic guide |
| Nitrates | Agricultural areas (Panhandle, Valley) | Nitrates guide |
| High TDS | West TX, Permian Basin | Water test guide |
| Bacteria | Statewide (shallow wells, flooding) | Bacteria guide |
| Iron | East TX, Gulf Coast | Iron guide |
| Fluoride | West TX (natural, can be very high) | Fluoride guide |
Have your test results? Get a plain-English diagnosis.
Analyze My Water TestTX Well Water by Region
Central TX / Hill Country (Austin, San Antonio)
Edwards and Trinity aquifers. Extremely hard water — often 20–50+ GPG. Limestone geology. A water softener is essential here[4].
West TX / Panhandle (Lubbock, Midland, Amarillo)
Ogallala Aquifer. Hard water, elevated arsenic, high TDS, and naturally high fluoride in some areas. Nitrates from irrigated agriculture[2].
East TX / Gulf Coast (Houston, Beaumont)
Gulf Coast Aquifer. Iron is the primary concern. Softer water than Central TX. Some areas have hydrogen sulfide[2].
South TX / Rio Grande Valley
Hard water, high TDS, and nitrates from agricultural runoff. Arsenic in some areas near the border[4].
Where to Get Tested in Texas
- Texas A&M AgriLife Extension — water testing services and clinics statewide[3].
- County health departments — some offer bacteria testing.
- Private certified labs — check TCEQ for certified lab listings[1].
- Mail-in services — Tap Score accepts TX samples ($100–$300).
What to Do Next
Never tested? This is urgent. Texas has no mandates. Contact Texas A&M AgriLife Extension or order a mail-in test.
Very hard water? You likely need a water softener. Central TX hardness is among the highest in the country.
Have results? Use our Water Test Interpreter.
Frequently Asked Questions
Does TX require well water testing?
No. Texas has zero private well testing requirements[1]. You are entirely responsible for your own water quality.
Why is TX well water so hard?
Limestone aquifers (Edwards, Trinity, Ogallala) dissolve calcium into the water[4]. Central TX and the Hill Country often exceed 20 GPG.
References
- Texas Commission on Environmental Quality. "Private Water Wells." 2024. https://www.tceq.texas.gov
- U.S. Geological Survey. "Groundwater Quality in Texas." NAWQA, 2023. https://www.usgs.gov/mission-areas/water-resources
- Texas A&M AgriLife Extension. "Private Water Well Testing." 2023.
- Texas Water Development Board. "Groundwater Resources." 2024. https://www.twdb.texas.gov
- U.S. Census Bureau. "Households Using Wells by State." 2021.
- TCEQ. "Rules for Water Well Drillers and Pump Installers." 2024.