Certified labs by state
Texas
In Texas, private well water is not regulated by the state, so homeowners are responsible for testing and treatment. For current guidance, residents mainly use TCEQ for accredited drinking-water laboratories, TWON for private-well education/testing guidance, and TWDB for groundwater data and occasional state sampling help.
Checked against official sources on October 4, 2026. Rules and links change; confirm with the office listed before you act.
- Certifies drinking water labs
- Texas Commission on Environmental Quality (TCEQ)
- Official certified lab list
- Official page →
- Free or low-cost testing
- TWDB says its Groundwater Monitoring program occasionally has funds for case-by-case private well sampling of naturally occurring constituents (not bacteria/pathogens), and TWON offers free well-owner trainings plus low-cost screening events in some counties.
Official resources in Texas
Official Texas page for residents; directs private well owners to accredited drinking-water laboratories.
Texas page with the accredited drinking-water laboratory map/table residents can use to find labs.
Official state-supported private well education program page; lists free trainings and well-screening events.
Current Texas guide with recommended private-well test panels and testing frequency.
Official state page explaining private-well sampling, owner responsibility, and occasional TWDB sampling assistance.
Key facts for Texas
- TCEQ recommends private well owners use an accredited drinking water laboratory for testing. (Source: TCEQ, "How is my Drinking Water Quality?")
- The State of Texas does not regulate private well water quality; private well owners are responsible for addressing water-quality problems. (Source: TWDB, "Sampling a Private Water Well")
- TWON recommends baseline testing for arsenic, nitrate, uranium, radionuclides, total coliform, pH, TDS, chloride, fluoride, hardness, iron, manganese, sodium, and sulfate. (Source: TWON Well Owner's Guide)
- TWON recommends testing private wells annually for total coliform bacteria and nitrate, and watching monthly for changes in turbidity, color, odor, and taste. (Source: TWON Well Owner's Guide)
- TWDB says radionuclides, including emissions from uranium, naturally occur in several Texas aquifers, and radon is generally a greater concern in air than in water. (Source: TWDB Groundwater Data)
- Regional examples from TWDB: West Texas Bolsons commonly exceed standards for arsenic, fluoride, gross alpha radiation, or nitrate-N in central/southern areas; some Blanco County wells in Central Texas's Marble Falls Aquifer have high nitrate. (Source: TWDB aquifer pages)
Helpful guides
- How to choose a state-certified drinking water lab
- What to test your private well water for (and how often)
- How to collect a well water sample without ruining the test
- How to read a water test report: MCLs, units and flags