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Cinco MUD 5

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
2,460 people
Connections
820
Water source
Groundwater bought from another system
Based in
Houston, TX
County
Fort Bend
Owner
Local government
The ZIP code it serves

77450

The short answer

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

What handles it

What was found

Total trihalomethanes (TTHM), haloacetic acids (HAA5) and nitrate: Texas’s own results, samples taken from Feb. 6, 2020 to Aug. 13, 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

36.9ppb

Highest yearly average, 2020 to 2026

2026 average: 10.0 ppb

Averaged by year, the highest was 36.9 ppb, in 2024, below EPA’s legal limit of 80 ppb. Its highest single sample was 126 ppb. In 2026, the latest year on file, its six samples averaged 10.0 ppb. EPA judges this limit at each sampling point, and recorded a violation for total trihalomethanes (TTHM) at this utility in 2025. Earlier, from 2012 to 2019, EPA’s file shows a highest yearly average of 60.4 ppb, in 2013.

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

9.2ppb

Highest yearly average, 2020 to 2026

2026 average: 2.7 ppb

Averaged by year, the highest was 9.2 ppb, in 2024, below EPA’s legal limit of 60 ppb. Its highest single sample was 29.4 ppb. In 2026, the latest year on file, its six samples averaged 2.7 ppb. Earlier, from 2012 to 2019, EPA’s file shows a highest yearly average of 3.8 ppb, in 2014.

What handles it

No certification claim covers this compound yet.

Nitrate

Comes from the source

Below EPA’s limits

0.11ppm

Highest sample; found in 2 of 7

2026: not found

The highest sample, in 2023, was 0.11 ppm, below EPA’s legal limit of 10 ppm. In 2026, the latest year on file, it wasn’t found in its one sample.

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, 20250.086 MG/LResolved
Health-based violations only. Resolved and archived mean the utility returned to compliance or the state closed the record. 1 monitoring or reporting violation 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. Cinco MUD 5’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. 6, 2020 to Aug. 13, 2026.

Testing your own tap

Cinco MUD 5’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 Cinco MUD 5 serves, in a straight line. Call first: certification is test by test, and not every lab takes samples from homeowners.

  • R&C Joy, Inc.

    Katy, TX · about 7 miles

    Certified for bacteria

    (281) 858-5988

  • ALS Laboratory Group, Environmental Services Division – Houston, Texas

    Houston, TX · about 11 miles

    Certified for lead and copper

    (281) 530-5656

  • Envirodyne Laboratories, Inc.

    Houston, TX · about 11 miles

    Certified for bacteria, lead and copper

    (281) 568-7880

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 TX0790291. Rebuilt from EPA data on Oct. 18, 2026.

Also in Fort Bend County

All Texas utilities

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