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Twin Buttes Water System

What EPA’s and Texas’s records show in this utility’s water: nitrate, arsenic and other regulated chemicals; lead and copper; and violations since 2016, with the certification that handles each result.

Serves
42 people
Connections
22
Water source
Surface water bought from another system
Based in
San Angelo, TX
County
Tom Green
Owner
Private
The ZIP code it serves

76904

The short answer

1 result is above EPA’s legal limit. The worst: Total trihalomethanes (TTHM), above the legal limit. 6 health-based violations since 2016.

What handles it

What was found

Total trihalomethanes (TTHM), haloacetic acids (HAA5) and nitrate: Texas’s own results, samples taken from March 4, 2020 to Sept. 3, 2026, with EPA’s 2012 to 2019 file for earlier years.

Above the legal limit1

Total trihalomethanes (TTHM)

Forms or is added in treatment

Above the legal limit

93ppb

Highest yearly average, 2020 to 2026

2026 average: 38.3 ppb

Averaged by year, the highest was 93 ppb, in 2024, above EPA’s legal limit of 80 ppb. Its highest single sample was 107 ppb. In 2026, the latest year on file, its three samples averaged 38.3 ppb. EPA recorded violations for total trihalomethanes (TTHM) at this utility in 2024 and 2025. Earlier, from 2012 to 2019, EPA’s file shows a highest yearly average of 83.3 ppb, in 2017, and EPA recorded a violation in 2017.

What handles it

  • NSF/ANSI 53 look for “Trihalomethanes (TTHM) Reduction”
  • NSF/ANSI 58 look for “Trihalomethanes (TTHM) Reduction”

Below EPA’s limits2

Haloacetic acids (HAA5)

Forms or is added in treatment

Below EPA’s limits

26.6ppb

Highest yearly average, 2020 to 2026

2026 average: 15.6 ppb

Averaged by year, the highest was 26.6 ppb, in 2024, below EPA’s legal limit of 60 ppb. Its highest single sample was 32.7 ppb. In 2026, the latest year on file, its three samples averaged 15.6 ppb. Earlier, from 2012 to 2019, EPA’s file shows a highest yearly average of 32.7 ppb, in 2019.

What handles it

No certification claim covers this compound yet.

Nitrate

Comes from the source

Below EPA’s limits

0.67ppm

Highest sample; found in 27 of 27

2026 average: 0.3 ppm

The highest sample, in 2020, was 0.67 ppm, below EPA’s legal limit of 10 ppm. In 2026, the latest year on file, its three samples averaged 0.3 ppm.

What handles it

  • NSF/ANSI 58 look for “Nitrate/Nitrite Reduction”
  • NSF/ANSI 53 look for “Nitrate/Nitrite (30 ppm challenge)”
One compound tested and not foundBelow the reporting level in every sample. Not found is not the same as zero.
  • Lead

What handles it

A certification covers specific claims, not a whole standard. Look for these claims on the certifier’s listing, not the box. Wording varies a little: NSF writes “Lead Reduction,” WQA just “Lead.”

  • NSF/ANSI 53

    Claim: Trihalomethanes (TTHM) Reduction

    For: Total trihalomethanes (TTHM)

    Other certifiers’ wording: VOC Reduction

  • NSF/ANSI 58

    Claim: Trihalomethanes (TTHM) Reduction

    For: Total trihalomethanes (TTHM)

At the tap, or for the whole house?

These come with the water itself, so a whole-house system certified for the same claims treats every tap and shower. A filter at the tap treats drinking water for much less. How whole-house systems compare.

Filters with those claims on a certifier’s listing

Disclosure: TapBuff earns a commission if you buy through some links on this page. It does not change which standard or filter we name. As an Amazon Associate, TapBuff earns from qualifying purchases. How TapBuff makes money

Compare five-year costs

Violations since 2016

Contaminant or ruleTypePeriodMeasuredStatus
TTHMThe running average was above the legal limit.EPA: Maximum Contaminant Level Violation, AverageJan. 1, 2025 to March 31, 20250.083 MG/LResolved
TTHMThe running average was above the legal limit.EPA: Maximum Contaminant Level Violation, AverageOct. 1, 2024 to Dec. 31, 20240.093 MG/LResolved
TTHMThe running average was above the legal limit.EPA: Maximum Contaminant Level Violation, AverageJuly 1, 2024 to Sept. 30, 20240.084 MG/LResolved
TTHMThe running average was above the legal limit.EPA: Maximum Contaminant Level Violation, AverageOct. 1, 2017 to Dec. 31, 20170.083 MG/LResolved
TTHMThe running average was above the legal limit.EPA: Maximum Contaminant Level Violation, AverageJuly 1, 2017 to Sept. 30, 20170.1 MG/LResolved
TTHMThe running average was above the legal limit.EPA: Maximum Contaminant Level Violation, AverageApril 1, 2017 to June 30, 20170.091 MG/LResolved
Health-based violations only. Resolved and archived mean the utility returned to compliance or the state closed the record. 14 monitoring or reporting violations not shown.

What this report can’t tell you

  • Everything else. Total trihalomethanes (TTHM), haloacetic acids (HAA5) and nitrate results here are Texas’s own from 2020 on, with EPA’s national file for 2012 to 2019. Twin Buttes Water System’s own annual report, which it must send you every year, has the contaminants this page does not show.

  • Your own plumbing. Lead results are the 90th percentile across homes the utility samples. Your home’s service line, solder and fixtures decide yours. A certified lab test is the only way to know.

  • What it means for your health. This page reports what the records show and EPA’s limits and goals; it is not medical advice. If you are worried about a health effect, talk to a doctor or your local health department.

  • Anything after the latest data. SDWIS data is from 2026 Q3; UCMR 5 didn’t sample this utility; Texas’s results run from March 4, 2020 to Sept. 3, 2026.

Testing your own tap

Twin Buttes Water System’s results are for the water it sends out. What your own service line, solder and fixtures add shows up only in a test of your tap, by a lab Texas certifies.

The lab Texas certifies closest to the area Twin Buttes Water System serves, in a straight line. Call first: certification is test by test, and not every lab takes samples from homeowners.

  • SKG Engineering, LLC

    San Angelo, TX · about 15 miles

    Certified for bacteria

    (325) 655-1288

Texas Well Owner Network, Texas A&M AgriLife Extension: Well Informed screening events, where well owners bring in water samples to be screened for common contaminants, followed by an hour-long session explaining the results. Upcoming events are on the network's calendar. Trainings, Texas Well Owner Network.

All 80 certified labs for Texas

Sources

PWSID TX2260026. Rebuilt from EPA data on Oct. 18, 2026.

Towns it serves

Also in Tom Green County

All Texas utilities

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