Well water testing in Wise County, Texas

What official data says about private wells in Wise County, what to test for, and the state-certified labs nearby.

People on private wells (2015)20,078

About 32% of the county's 62,953 residents. Rank 13 of 254 in Texas.

Arsenic above EPA’s limit (USGS estimate)about 553 people

95% range 441 to 705 private-well users (2010 base year). Rank 33 of 254 in Texas.

EPA radon zone (indoor air)Zone 3

Low potential (average indoor radon may be less than 2 pCi/L). EPA says the map should not be used to decide whether an individual home needs testing.

Certified labs in this county0

Labs with an address in this county, from the official state lists on this site, matched by ZIP code.

What to test for in Wise County

Private wells are not regulated like public water: EPA advises owners to test their well every year for total coliform bacteria, nitrates, total dissolved solids and pH. Your state's own schedule:

  • The Texas Well Owner Network (Texas A&M AgriLife Extension) recommends testing well water every year, at least for E. coli, even if the water looks and tastes fine. source

Arsenic. USGS estimates that about 553 people using private wells in Wise County had arsenic above 10 µg/L, EPA's limit for public water (2010 base year; 95% range 441 to 705). USGS describes this kind of estimate as useful "for broad screening of the population at risk", so it says nothing certain about any one well. Arsenic has no taste or smell: test for it by name.

Radon. EPA puts Wise County in Zone 3: low potential (average indoor radon may be less than 2 pCi/L). That map is about radon in indoor air, and EPA says it should not be used to decide whether an individual home needs testing. If radon is found in your air and you have a well, EPA suggests testing the water too: see radon in well water.

For anything specific to your home (farms nearby, old plumbing, a new baby, a smell or stain), use the which-tests checklist. When the results arrive, check your numbers against EPA's limits.

Estimated private-well users with arsenic above 10 µg/L: Wise County and Texas's highest countiespeople (2010 base year)
Show the numbers
ItemValueNote
Lubbock County11,642 people (2010 base year)
Midland County7,306 people (2010 base year)
Harris County6,396 people (2010 base year)
Ector County5,449 people (2010 base year)
Montgomery County3,720 people (2010 base year)
Wise County (this county)553 people (2010 base year)

USGS model estimate for broad screening, not a measurement of any well. Only a test tells you about your own well. Source: USGS, Estimated county level domestic well population with arsenic greater than 10 micrograms per liter (Ayotte, Medalie and Qi, 2017), accessed 2026-11-01.

PFAS in public water near Wise County (public supply, not your well)

This is public water data, not your well. A private well draws its own groundwater, which can have more or less PFAS than the public supply nearby. Only a test of your well tells you.

Under EPA’s fifth Unregulated Contaminant Monitoring Rule (UCMR 5), public water systems sampled their water for 29 PFAS between Jan 3, 2023 and Jun 17, 2026. 6 public systems that serve ZIP codes mainly in Wise County reported results. 0 of them had at least one sample with PFOA or PFOS at or above 4.0 ng/L, and 4 had at least one of the 29 PFAS measured at or above its reporting level.

4.0 ng/L (parts per trillion) is both EPA’s UCMR 5 reporting level for PFOA and PFOS and the number in EPA’s 2024 limit for public water. That limit is judged on a running annual average, so one sample at that level is not a violation. EPA proposed changes to its PFAS rules in May 2026: see PFAS in well water for the current status and who should test a well. To test your own well, find a lab certified for PFAS.

Method: a system counts for this county when it reports serving a ZIP code whose largest land part is in this county, so a system serving several counties counts in each. Source: U.S. EPA, UCMR 5 occurrence data (by state), file dated Oct 15, 2026; downloaded Nov 1, 2026.

Testing programs and help in Texas

  • The Texas Well Owner Network holds well water screening events, such as its June 2026 events in South Texas. Samples are screened for total coliform bacteria, E. coli, nitrate-nitrogen, arsenic and salinity, followed by a results meeting. At the June 2026 South Texas events the fee was $15 per sample in some areas (Robstown, Sinton and Refugio) and free in others, so check each event. source
  • The Texas Water Development Board says some groundwater conservation districts test well water for free or at a reduced cost. Its GCD Index shows whether your address is in a district. source
  • The Texas Water Development Board's groundwater monitoring program occasionally has funds to sample private wells case by case. It tests naturally occurring constituents only, not bacteria. source

Buying a home with a well in Wise County

Loan test (FHA, VA, USDA) in Wise County, TX

  • VA. Test results are valid for 90 days from the date the local health authority certifies them, unless the local authority says otherwise. VA’s chapter names no list of contaminants: the water must meet the local health authority’s requirements, or EPA guidelines where it has none. Your lender may ask for specific tests.
  • FHA. A well test is required in the situations FHA’s handbook lists, among others, and the report may not be more than 180 days old at disbursement.
  • USDA. Guaranteed loans need a water quality test for a private well, done by the local health authority or a state-certified lab, and no more than 180 days old at closing.

Lenders can ask for more (extra tests, a particular lab, who takes the sample): ask your lender before you book. Federal rules as read on Nov 3, 2026 source 1 source 2 source 3. Full comparison: VA, FHA and USDA well water test requirements. Loan test kits sold by mail, with price and days to results: kits compared.

State-certified labs in Wise County

None of the labs on our Texas list has an address in Wise County. Labs elsewhere in the state may take samples by mail or courier: ask the lab, and check the hold time for bacteria before you send one.

Labs on the Texas list whose own websites say they take homeowner samples: Angelina and Neches River Authority Environmental Laboratory (Lufkin), City of Houston Health Department, Bureau of Laboratory Services (Houston), Edwards Aquifer Research and Data Center (San Marcos), Guadalupe-Blanco River Authority Regional Laboratory (Seguin), Integrity Testing, Inc. (Austin), Lower Colorado River Authority - Environmental Laboratory Services (Austin), SPL, Inc – Kilgore (Kilgore), SPL, Inc. – Plano (Plano) and 4 more. Use Check my ZIP to sort labs by distance.

See all Texas labs in the finder and filter by the test you need and by labs that take homeowner samples.

Sources and method Private-well population is the USGS 2015 estimate of people on domestic self-supplied water. The arsenic figure is a USGS model estimate on a 2010 population base, not a count of tested wells. Labs are placed in a county by the ZIP code on the state list. These figures come from different USGS products, years and methods, so they can disagree with each other (for example, the arsenic estimate and the well population use different base years). Read them as context for the county, not as facts about any one well. Checked 1 Nov 2026. General information, not medical advice.
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