Skip to content
TapBuff
ZIP

La Plata West Water Authority

What EPA’s and Colorado’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
354 people
Connections
164
Water source
Surface water bought from another system
Based in
Hesperus, CO
County
La Plata
Owner
Public and private
The ZIP code it serves

81326

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) and haloacetic acids (HAA5): Colorado’s own results, samples taken from Nov. 5, 2020 to Aug. 11, 2026.

Above the legal limit1

Total trihalomethanes (TTHM)

Forms or is added in treatment

Above the legal limit

124ppb

Highest yearly average, 2020 to 2026

2026, one sample: 64 ppb

Averaged by year, the highest was 124 ppb, in 2020, above EPA’s legal limit of 80 ppb. In 2026, the latest year on file, its one sample was 64 ppb. EPA recorded a violation for total trihalomethanes (TTHM) at this utility in 2021.

What handles it

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

Below EPA’s limits1

Haloacetic acids (HAA5)

Forms or is added in treatment

Below EPA’s limits

42.3ppb

Highest yearly average, 2020 to 2026

2026, one sample: 20.9 ppb

Averaged by year, the highest was 42.3 ppb, in 2023, below EPA’s legal limit of 60 ppb. Its highest single sample was 80 ppb. In 2026, the latest year on file, its one sample was 20.9 ppb. EPA recorded no violation for haloacetic acids (HAA5) at this utility since 2020.

What handles it

No certification claim covers this compound yet.

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, AverageJuly 1, 2021 to Sept. 30, 20210.083 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) and haloacetic acids (HAA5) results here are Colorado’s own from 2020 on, with EPA’s national file for 2012 to 2019. La Plata West Water Authority’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; Colorado’s results run from Nov. 5, 2020 to Aug. 11, 2026.

Testing your own tap

La Plata West Water Authority’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 Colorado certifies.

The lab Colorado certifies closest to the area La Plata West Water Authority serves, in a straight line. Call first: certification is test by test, and not every lab takes samples from homeowners.

  • La Plata County Water Quality Laboratory

    Durango, CO · about 17 miles

    Certified for bacteria

All 54 certified labs for Colorado

Sources

PWSID CO0134466. Rebuilt from EPA data on Oct. 18, 2026.

Also in La Plata County

All Colorado utilities

What to do next