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Mirando City 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
460 people
Connections
280
Water source
Groundwater
Based in
Mirando City, TX
County
Webb
Owner
Local government
The ZIP code it serves

78369

The short answer

1 result is above EPA’s legal limit, and 1 more is above the health goal. The worst: Arsenic, above the legal limit. 9 health-based violations since 2016.

What handles it

What was found

Arsenic, uranium, nitrate, fluoride, total trihalomethanes (TTHM), haloacetic acids (HAA5) and chromium (total): Texas’s own results, samples taken from Feb. 4, 2020 to Aug. 24, 2026, with EPA’s 2012 to 2019 file for earlier years.

Above the legal limit1

Arsenic

Comes from the source

Above the legal limit

14.1ppb

Highest yearly average, 2020 to 2026

2026 average: 9.3 ppb

Averaged by year, the highest was 14.1 ppb, in 2024, above EPA’s legal limit of 10 ppb. Its highest single sample was 19.8 ppb. In 2026, the latest year on file, its three samples averaged 9.3 ppb. EPA recorded violations for arsenic at this utility in 2024 and 2025. Earlier, from 2012 to 2019, EPA’s file shows a highest yearly average of 9.1 ppb, in 2013.

What handles it

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

Above the health goal1

Uranium

Comes from the source

Above the health goal

1.8ppb

Highest yearly average, 2020 to 2026

Averaged by year, the highest was 1.8 ppb, in 2026: below EPA’s legal limit of 30 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 1.4 ppb, in 2014.

What handles it

Below EPA’s limits4

Nitrate

Comes from the source

Below EPA’s limits

10.1ppm

Highest sample; found in 27 of 27

2026 average: 7.2 ppm

The highest sample, in 2021, was 10.1 ppm, which EPA rounds to 10 ppm to compare: at its legal limit of 10 ppm, not above it. In 2026, the latest year on file, its three samples averaged 7.2 ppm. EPA recorded no violation for nitrate at this utility since 2020. Earlier, from 2012 to 2019, EPA’s file shows a highest sample of 11 ppm, in 2018, and EPA recorded a violation in 2018.

What handles it

  • NSF/ANSI 58 look for “Nitrate/Nitrite Reduction”
  • NSF/ANSI 53 look for “Nitrate/Nitrite (30 ppm challenge)”

Fluoride

Forms or is added in treatment

Below EPA’s limits

0.58ppm

Highest yearly average, 2020 to 2026

2026, one sample: 0.51 ppm

Averaged by year, the highest was 0.58 ppm, in 2023, below EPA’s legal limit of 4.0 ppm. In 2026, the latest year on file, its one sample was 0.51 ppm. Earlier, from 2012 to 2019, EPA’s file shows a highest yearly average of 0.29 ppm, in 2017.

What handles it

Total trihalomethanes (TTHM)

Forms or is added in treatment

Below EPA’s limits

1.9ppb

Highest yearly average, 2022 to 2025

Averaged by year, the highest was 1.9 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 15 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

1.0ppb

Highest yearly average, 2022 to 2025

2025: not found

Averaged by year, the highest was 1.0 ppb, in 2022, below EPA’s legal limit of 60 ppb. 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 3.8 ppb, in 2016.

What handles it

No certification claim covers this compound yet.

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

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The best reverse osmosis systems, ranked

Violations since 2016

Contaminant or ruleTypePeriodMeasuredStatus
ArsenicThe running average was above the legal limit.EPA: Maximum Contaminant Level Violation, AverageJuly 1, 2025 to Sept. 30, 20250.011 MG/LResolved
ArsenicThe running average was above the legal limit.EPA: Maximum Contaminant Level Violation, AverageApril 1, 2025 to June 30, 20250.013 MG/LResolved
ArsenicThe running average was above the legal limit.EPA: Maximum Contaminant Level Violation, AverageJan. 1, 2025 to March 31, 20250.015 MG/LResolved
Lead and Copper Rule RevisionsThe required inventory of lead service lines was not completed or submitted on time.EPA: LSL InventoryOct. 17, 2024—Unaddressed
ArsenicThe running average was above the legal limit.EPA: Maximum Contaminant Level Violation, AverageOct. 1, 2024 to Dec. 31, 20240.014 MG/LResolved
ArsenicThe running average was above the legal limit.EPA: Maximum Contaminant Level Violation, AverageJuly 1, 2024 to Sept. 30, 20240.012 MG/LResolved
ArsenicThe running average was above the legal limit.EPA: Maximum Contaminant Level Violation, AverageApril 1, 2024 to June 30, 20240.011 MG/LResolved
ArsenicThe running average was above the legal limit.EPA: Maximum Contaminant Level Violation, AverageJan. 1, 2024 to March 31, 20240.011 MG/LResolved
NitrateA sample was above the legal limit, for a contaminant judged one sample at a time.EPA: Maximum Contaminant Level Violation, Single SampleJan. 1, 2018 to March 31, 201811 MG/LResolved
Health-based violations only. Resolved and archived mean the utility returned to compliance or the state closed the record. 17 monitoring or reporting violations not shown.

What this report can’t tell you

  • Everything else. Arsenic, uranium, nitrate, fluoride, total trihalomethanes (TTHM), haloacetic acids (HAA5) and chromium (total) results here are Texas’s own from 2020 on, with EPA’s national file for 2012 to 2019. Mirando City 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. 4, 2020 to Aug. 24, 2026.

Testing your own tap

Mirando City 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 lab Texas certifies closest to the area Mirando City WSC serves, in a straight line. Call first: certification is test by test, and not every lab takes samples from homeowners.

  • City of Laredo Health Department Lab

    Laredo, TX · about 33 miles

    Certified for bacteria

    (956) 795-4908

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 TX2400025. Rebuilt from EPA data on Oct. 18, 2026.

Nearby

All Texas utilities

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