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Shiro 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
103 people
Connections
118
Water source
Groundwater
Based in
Anderson, TX
County
Grimes
Owner
Private
The ZIP code it serves

77873

The short answer

2 results are above the health goal. The worst: Arsenic, above the health goal. 1 health-based violation since 2016.

What handles it

What was found

Arsenic, total trihalomethanes (TTHM), haloacetic acids (HAA5), fluoride, nitrate and chromium (total): Texas’s own results, samples taken from March 23, 2020 to July 15, 2025, with EPA’s 2012 to 2019 file for earlier years.

Uranium: EPA’s compliance monitoring file, samples taken from Sept. 13, 2017 to Sept. 13, 2017. Newer results are in the utility’s annual water quality report.

Above the health goal2

Arsenic

Comes from the source

Above the health goal

5.7ppb

Highest yearly average, 2020 to 2023

Averaged by year, the highest was 5.7 ppb, in 2023: below EPA’s legal limit of 10 ppb, but above its health goal of zero. That was also the latest year on file. Earlier, from 2012 to 2019, EPA’s file shows a highest yearly average of 6.9 ppb, in 2017.

What handles it

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

Uranium

Comes from the source

Above the health goal

1.0ppb

Highest yearly average, 2017

Averaged by year, the highest was 1.0 ppb, in 2017: below EPA’s legal limit of 30 ppb, but above its health goal of zero. That is the only year on file.

What handles it

Below EPA’s limits4

Total trihalomethanes (TTHM)

Forms or is added in treatment

Below EPA’s limits

17.5ppb

Highest yearly average, 2022 to 2025

Averaged by year, the highest was 17.5 ppb, in 2025, below EPA’s legal limit of 80 ppb. That was also the latest year on file. Earlier, from 2012 to 2019, EPA’s file shows a highest yearly average of 9.5 ppb, in 2016.

What handles it

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

Haloacetic acids (HAA5)

Forms or is added in treatment

Below EPA’s limits

3.0ppb

Highest yearly average, 2022 to 2025

Averaged by year, the highest was 3.0 ppb, in 2025, below EPA’s legal limit of 60 ppb. That was also the latest year on file. Earlier, from 2012 to 2019, EPA’s file shows a highest yearly average of 1.9 ppb, in 2019.

What handles it

No certification claim covers this compound yet.

Fluoride

Forms or is added in treatment

Below EPA’s limits

0.12ppm

Highest yearly average, 2022 to 2025

2025: not found

Averaged by year, the highest was 0.12 ppm, in 2022, below EPA’s legal limit of 4.0 ppm. 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 0.18 ppm, in 2016.

What handles it

Nitrate

Comes from the source

Below EPA’s limits

0.17ppm

Highest sample; found in 5 of 6

2025: not found

The highest sample, in 2024, was 0.17 ppm, below EPA’s legal limit of 10 ppm. 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 sample of 0.15 ppm, in 2012.

What handles it

  • NSF/ANSI 58 look for “Nitrate/Nitrite Reduction”
  • NSF/ANSI 53 look for “Nitrate/Nitrite (30 ppm challenge)”
2 compounds tested and not foundBelow the reporting level in every sample. Not found is not the same as zero.
  • Chromium (total)
  • 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: Arsenic (Pentavalent)<=50 ppb Reduction

    For: Arsenic

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

  • NSF/ANSI 58

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

    For: Arsenic, Uranium

    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
Lead and Copper Rule RevisionsThe required inventory of lead service lines was not completed or submitted on time.EPA: LSL InventoryOct. 17, 2024—Addressed
Health-based violations only. Resolved and archived mean the utility returned to compliance or the state closed the record. 48 monitoring or reporting violations not shown.

What this report can’t tell you

  • Everything else. Arsenic, total trihalomethanes (TTHM), haloacetic acids (HAA5), fluoride, nitrate and chromium (total) results here are Texas’s own from 2020 on, with EPA’s national file for 2012 to 2019. Uranium comes from EPA’s file alone, which ends in 2019. Shiro Water System’s own annual report, which it must send you every year, has newer results for those and 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 23, 2020 to July 15, 2025; EPA’s compliance samples are from Sept. 13, 2017 to Sept. 13, 2017.

Testing your own tap

Shiro 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 3 labs Texas certifies closest to the area Shiro Water System serves, in a straight line. Call first: certification is test by test, and not every lab takes samples from homeowners.

  • Chaparral Laboratories, Inc.

    Huntsville, TX · about 22 miles

    Certified for bacteria, lead and copper

    (936) 291-1881

  • Nova Biologicals, Inc.

    Conroe, TX · about 28 miles

    Certified for bacteria

    (936) 756-5333

  • Eastex Environmental Lab, Inc. -Coldspring

    Coldspring, TX · about 38 miles

    Certified for bacteria, lead and copper

    (936) 653-3249

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 TX0930014. Rebuilt from EPA data on Oct. 18, 2026.

Also in Grimes County

All Texas utilities

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