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Town of Olla Water System

What EPA’s and CDC’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
2,565 people
Connections
855
Water source
Groundwater
Based in
Olla, LA
County
La Salle Parish
Owner
Local government
The ZIP code it serves

71465

The short answer

1 result is above EPA’s legal limit. The worst: Total trihalomethanes (TTHM), above the legal limit. 9 health-based violations since 2016.

What handles it

What was found

Total trihalomethanes (TTHM), haloacetic acids (HAA5) and nitrate: Louisiana’s yearly averages per water system, as CDC’s Environmental Public Health Tracking Network publishes them, 2020 to 2022, with EPA’s 2012 to 2019 file for earlier years.

Fluoride, arsenic, chromium (total) and uranium: EPA’s compliance monitoring file, samples taken from Dec. 3, 2012 to July 18, 2017. Newer results are in the utility’s annual water quality report.

Above the legal limit1

Total trihalomethanes (TTHM)

Forms or is added in treatment

Above the legal limit

72.9ppb

Highest yearly average, 2020 to 2022

2022 average: 66.9 ppb

Averaged by year, the highest was 72.9 ppb, in 2021, below EPA’s legal limit of 80 ppb. In 2022, the latest year on file, it averaged 66.9 ppb. EPA judges this limit at each sampling point, and recorded a violation for total trihalomethanes (TTHM) at this utility in 2021. Earlier, from 2012 to 2019, EPA’s file shows a highest yearly average of 100 ppb, in 2013, and EPA recorded violations in 2014, 2017, 2018 and 2019.

What handles it

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

Below EPA’s limits3

Haloacetic acids (HAA5)

Forms or is added in treatment

Below EPA’s limits

16.8ppb

Highest yearly average, 2020 to 2022

2022 average: 13.5 ppb

Averaged by year, the highest was 16.8 ppb, in 2020, below EPA’s legal limit of 60 ppb. In 2022, the latest year on file, it averaged 13.5 ppb. Earlier, from 2012 to 2019, EPA’s file shows a highest yearly average of 21.8 ppb, in 2013.

What handles it

No certification claim covers this compound yet.

Fluoride

Forms or is added in treatment

Below EPA’s limits

0.24ppm

Highest yearly average, 2012 to 2017

2017 average: 0.23 ppm

Averaged by year, the highest was 0.24 ppm, in 2016, below EPA’s legal limit of 4.0 ppm. Its highest single sample was 0.3 ppm. In 2017, the latest year on file, its three samples averaged 0.23 ppm.

What handles it

Nitrate

Comes from the source

Below EPA’s limits

0.2ppm

Highest yearly average, 2022

Averaged by year, the highest was 0.2 ppm, in 2022, below EPA’s legal limit of 10 ppm. That is the only year on file. Earlier, from 2012 to 2019, EPA’s file shows a highest sample of 0.11 ppm, in 2019.

What handles it

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

    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, AverageOct. 1, 2021 to Dec. 31, 20210.083 MG/LResolved
TTHMThe running average was above the legal limit.EPA: Maximum Contaminant Level Violation, AverageApril 1, 2021 to June 30, 20210.084 MG/LResolved
TTHMThe running average was above the legal limit.EPA: Maximum Contaminant Level Violation, AverageJan. 1, 2019 to March 31, 20190.094 MG/LResolved
TTHMThe running average was above the legal limit.EPA: Maximum Contaminant Level Violation, AverageOct. 1, 2018 to Dec. 31, 20180.093 MG/LResolved
TTHMThe running average was above the legal limit.EPA: Maximum Contaminant Level Violation, AverageJuly 1, 2018 to Sept. 30, 201896 UG/LResolved
TTHMThe running average was above the legal limit.EPA: Maximum Contaminant Level Violation, AverageApril 1, 2018 to June 30, 201898 UG/LResolved
TTHMThe running average was above the legal limit.EPA: Maximum Contaminant Level Violation, AverageJan. 1, 2018 to March 31, 2018104 UG/LResolved
TTHMThe running average was above the legal limit.EPA: Maximum Contaminant Level Violation, AverageOct. 1, 2017 to Dec. 31, 2017108 UG/LResolved
TTHMThe running average was above the legal limit.EPA: Maximum Contaminant Level Violation, AverageJuly 1, 2017 to Sept. 30, 2017119 UG/LResolved
Health-based violations only. Resolved and archived mean the utility returned to compliance or the state closed the record. 3 monitoring or reporting violations not shown.

What this report can’t tell you

  • Everything else. Total trihalomethanes (TTHM), haloacetic acids (HAA5) and nitrate results here are Louisiana’s yearly averages as CDC publishes them, from 2020 on, with EPA’s national file for 2012 to 2019. Fluoride, arsenic, chromium (total) and uranium come from EPA’s file alone, which ends in 2019. Town of Olla 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; CDC’s yearly averages for Louisiana cover 2020 to 2022; EPA’s compliance samples are from Dec. 3, 2012 to July 18, 2017.

Testing your own tap

Town of Olla 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 Louisiana certifies.

The lab Louisiana certifies closest to the area Town of Olla Water System serves, in a straight line. Call first: certification is test by test, and not every lab takes samples from homeowners.

  • LDH Rapides Regional Laboratory

    Alexandria, LA · about 47 miles

    Certified for bacteria

    (318) 487-5282

All 48 certified labs for Louisiana

Sources

PWSID LA1059004. Rebuilt from EPA data on Oct. 18, 2026.

Nearby

All Louisiana utilities

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