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Central Washington County WSC

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
2,270 people
Connections
980
Water source
Groundwater
Based in
Brenham, TX
County
Washington
Owner
Local government
The 2 ZIP codes it serves

77833, 77835

The short answer

1 result is above EPA’s legal limit, and 1 more is above the health goal. The worst: Total trihalomethanes (TTHM), above the legal limit. 14 health-based violations since 2016.

What handles it

What was found

Total trihalomethanes (TTHM), arsenic, haloacetic acids (HAA5), fluoride, nitrate, chromium (total) and uranium: Texas’s own results, samples taken from Feb. 10, 2020 to Aug. 4, 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

81.3ppb

Highest yearly average, 2020 to 2026

2026 average: 38 ppb

Averaged by year, the highest was 81.3 ppb, in 2023, above EPA’s legal limit of 80 ppb. Its highest single sample was 121 ppb. In 2026, the latest year on file, its six samples averaged 38 ppb. EPA recorded violations for total trihalomethanes (TTHM) at this utility in 2021, 2022, 2023, 2024 and 2025. Earlier, from 2012 to 2019, EPA’s file shows a highest yearly average of 69.4 ppb, in 2015, and EPA recorded a violation in 2016.

What handles it

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

Above the health goal1

Arsenic

Comes from the source

Above the health goal

5.3ppb

Highest yearly average, 2021 to 2025

2025: not found

Averaged by year, the highest was 5.3 ppb, in 2021: below EPA’s legal limit of 10 ppb, but above its health goal of zero. In 2025, the latest year on file, it wasn’t found in its one sample. Earlier, from 2012 to 2019, EPA’s file shows a highest yearly average of 7.9 ppb, in 2015.

What handles it

  • NSF/ANSI 58 look for “Arsenic (Pentavalent)<=50 ppb Reduction”
  • NSF/ANSI 53 look for “Arsenic (Pentavalent)<=50 ppb Reduction”

Below EPA’s limits3

Haloacetic acids (HAA5)

Forms or is added in treatment

Below EPA’s limits

12.6ppb

Highest yearly average, 2020 to 2026

2026 average: 7.8 ppb

Averaged by year, the highest was 12.6 ppb, in 2022, below EPA’s legal limit of 60 ppb. Its highest single sample was 21.2 ppb. In 2026, the latest year on file, its six samples averaged 7.8 ppb. Earlier, from 2012 to 2019, EPA’s file shows a highest yearly average of 12.1 ppb, in 2018.

What handles it

No certification claim covers this compound yet.

Fluoride

Forms or is added in treatment

Below EPA’s limits

0.46ppm

Highest yearly average, 2021 to 2024

Averaged by year, the highest was 0.46 ppm, in 2024, below EPA’s legal limit of 4.0 ppm. Its highest single sample was 0.52 ppm. That was also the latest year on file. Earlier, from 2012 to 2019, EPA’s file shows a highest yearly average of 0.53 ppm, in 2012.

What handles it

Nitrate

Comes from the source

Below EPA’s limits

0.41ppm

Highest sample; found in 12 of 14

2026: not found

The highest sample, in 2022, was 0.41 ppm, below EPA’s legal limit of 10 ppm. In 2026, the latest year on file, it wasn’t found in any of its two samples. Earlier, from 2012 to 2019, EPA’s file shows a highest sample of 0.37 ppm, in 2019.

What handles it

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

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

    Claims: Trihalomethanes (TTHM) Reduction, Arsenic (Pentavalent)<=50 ppb Reduction

    For: Total trihalomethanes (TTHM), Arsenic

    Other certifiers’ wording: VOC Reduction; Arsenic (III) (50 ppb influent level)

  • NSF/ANSI 58

    Claims: Trihalomethanes (TTHM) Reduction, Arsenic (Pentavalent)<=50 ppb Reduction

    For: Total trihalomethanes (TTHM), Arsenic

    Other certifiers’ wording: Arsenic (Pentavalent)<=300 ppb Reduction; Arsenic (V) (300 ppb influent level)

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

The best reverse osmosis systems, ranked

Violations since 2016

Contaminant or ruleTypePeriodMeasuredStatus
TTHMThe running average was above the legal limit.EPA: Maximum Contaminant Level Violation, AverageJuly 1, 2025 to Sept. 30, 20250.082 MG/LResolved
TTHMThe running average was above the legal limit.EPA: Maximum Contaminant Level Violation, AverageApril 1, 2024 to June 30, 20240.085 MG/LResolved
TTHMThe running average was above the legal limit.EPA: Maximum Contaminant Level Violation, AverageJan. 1, 2024 to March 31, 20240.084 MG/LResolved
TTHMThe running average was above the legal limit.EPA: Maximum Contaminant Level Violation, AverageOct. 1, 2023 to Dec. 31, 20230.087 MG/LResolved
TTHMThe running average was above the legal limit.EPA: Maximum Contaminant Level Violation, AverageJuly 1, 2023 to Sept. 30, 20230.083 MG/LResolved
TTHMThe running average was above the legal limit.EPA: Maximum Contaminant Level Violation, AverageApril 1, 2023 to June 30, 20230.081 MG/LResolved
TTHMThe running average was above the legal limit.EPA: Maximum Contaminant Level Violation, AverageJan. 1, 2023 to March 31, 20230.084 MG/LResolved
TTHMThe running average was above the legal limit.EPA: Maximum Contaminant Level Violation, AverageOct. 1, 2022 to Dec. 31, 20220.084 MG/LResolved
TTHMThe running average was above the legal limit.EPA: Maximum Contaminant Level Violation, AverageJuly 1, 2022 to Sept. 30, 20220.083 MG/LResolved
TTHMThe running average was above the legal limit.EPA: Maximum Contaminant Level Violation, AverageApril 1, 2022 to June 30, 20220.095 MG/LResolved
TTHMThe running average was above the legal limit.EPA: Maximum Contaminant Level Violation, AverageJan. 1, 2022 to March 31, 20220.088 MG/LResolved
TTHMThe running average was above the legal limit.EPA: Maximum Contaminant Level Violation, AverageOct. 1, 2021 to Dec. 31, 20210.085 MG/LResolved
TTHMThe running average was above the legal limit.EPA: Maximum Contaminant Level Violation, AverageApril 1, 2016 to June 30, 20160.081 MG/LResolved
TTHMThe running average was above the legal limit.EPA: Maximum Contaminant Level Violation, AverageJan. 1, 2016 to March 31, 20160.081 MG/LResolved
Health-based violations only. Resolved and archived mean the utility returned to compliance or the state closed the record. 7 monitoring or reporting violations not shown.

What this report can’t tell you

  • Everything else. Total trihalomethanes (TTHM), arsenic, haloacetic acids (HAA5), fluoride, nitrate, chromium (total) and uranium results here are Texas’s own from 2020 on, with EPA’s national file for 2012 to 2019. Central Washington County WSC’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 Feb. 10, 2020 to Aug. 4, 2026.

Testing your own tap

Central Washington County WSC’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 3 labs Texas certifies closest to the area Central Washington County WSC serves, in a straight line. Call first: certification is test by test, and not every lab takes samples from homeowners.

  • Aqua-Tech Laboratories, Inc.

    Bryan, TX · about 33 miles

    Certified for bacteria, lead and copper

    (979) 778-3707

  • R&C Joy, Inc.

    Katy, TX · about 52 miles

    Certified for bacteria

    (281) 858-5988

  • Eurofins EMLab P&K – Houston

    Houston, TX · about 60 miles

    Certified for bacteria

    (281) 940-2580

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 TX2390055. Rebuilt from EPA data on Oct. 18, 2026.

Towns it serves

Also in Washington County

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