Greenbriar Prairie Basse 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
- 1,656 people
- Connections
- 552
- Water source
- Groundwater
- Based in
- Sunset, LA
- County
- St. Landry Parish
- Owner
- Private
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 itWhat was found
Copper: EPA’s file records a utility’s copper only when it exceeds the action level. The last here was 1.5 ppm, for the period ending June 30, 2019. None since is on file, so it is not counted as a current finding.
Total trihalomethanes (TTHM), nitrate and haloacetic acids (HAA5): 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.
Arsenic, uranium, fluoride and chromium (total): EPA’s compliance monitoring file, samples taken from March 4, 2013 to Oct. 15, 2018. Newer results are in the utility’s annual water quality report.
Above the health goal2
Arsenic
Comes from the source
2.5ppb
Highest yearly average, 2013 to 2018
2018 average: 1.6 ppb
Averaged by year, the highest was 2.5 ppb, in 2013: below EPA’s legal limit of 10 ppb, but above its health goal of zero. Its highest single sample was 3.0 ppb. In 2018, the latest year on file, its two samples averaged 1.6 ppb.
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
0.74ppb
Highest yearly average, 2013 to 2018
2018: not found
Averaged by year, the highest was 0.74 ppb, in 2013: below EPA’s legal limit of 30 ppb, but above its health goal of zero. Its highest single sample was 1.5 ppb. In 2018, the latest year on file, it wasn’t found in any of its two samples.
What handles it
- NSF/ANSI 58 look for “Uranium”
Below EPA’s limits4
Fluoride
Forms or is added in treatment
0.39ppm
Highest yearly average, 2013 to 2018
2018 average: 0.25 ppm
Averaged by year, the highest was 0.39 ppm, in 2016, below EPA’s legal limit of 4.0 ppm. Its highest single sample was 0.41 ppm. In 2018, the latest year on file, its two samples averaged 0.25 ppm.
What handles it
- NSF/ANSI 58 look for “Fluoride Reduction”
- NSF/ANSI 53 look for “Fluoride”
Total trihalomethanes (TTHM)
Forms or is added in treatment
5.3ppb
Highest yearly average, 2020 to 2022
2022 average: 3.5 ppb
Averaged by year, the highest was 5.3 ppb, in 2020, below EPA’s legal limit of 80 ppb. In 2022, the latest year on file, it averaged 3.5 ppb. Earlier, from 2012 to 2019, EPA’s file shows a highest yearly average of 6.3 ppb, in 2019.
What handles it
- NSF/ANSI 53 look for “Trihalomethanes (TTHM) Reduction”
- NSF/ANSI 58 look for “Trihalomethanes (TTHM) Reduction”
Nitrate
Comes from the source
0.4ppm
Highest yearly average, 2022
Averaged by year, the highest was 0.4 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 0.53 ppm, in 2016.
What handles it
- NSF/ANSI 58 look for “Nitrate/Nitrite Reduction”
- NSF/ANSI 53 look for “Nitrate/Nitrite (30 ppm challenge)”
Haloacetic acids (HAA5)
Forms or is added in treatment
1.5ppb
Highest yearly average, 2020 to 2022
2022 average: 0.61 ppb
Averaged by year, the highest was 1.5 ppb, in 2020, below EPA’s legal limit of 60 ppb. In 2022, the latest year on file, it averaged 0.61 ppb. Earlier, from 2012 to 2019, EPA’s file shows a highest yearly average of 7.0 ppb, in 2013.
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
Countertop reverse osmosis
- IAPMO listing:NSF/ANSI 42NSF/ANSI 53NSF/ANSI 58NSF/ANSI 401checked Oct. 4, 2026
Certified for: Arsenic
Aquasana SmartFlow Reverse Osmosis (AQ-SFRO2)
Under-sink reverse osmosis
- WQA listing:NSF/ANSI 42NSF/ANSI 53NSF/ANSI 58NSF/ANSI 401checked Oct. 9, 2026
Certified for: Arsenic
Brondell Capella RC250 Reverse Osmosis System
Under-sink reverse osmosis
- WQA listing:NSF/ANSI 42NSF/ANSI 53NSF/ANSI 58NSF/ANSI 401checked Oct. 9, 2026
Certified for: Arsenic
Violations since 2016
| Contaminant or rule | Type | Period | Measured | Status |
|---|---|---|---|---|
| Lead and Copper Rule Revisions | The required inventory of lead service lines was not completed or submitted on time.EPA: LSL Inventory | Oct. 17, 2024 | — | Resolved |
| 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), nitrate and haloacetic acids (HAA5) results here are Louisiana’s yearly averages as CDC publishes them, from 2020 on, with EPA’s national file for 2012 to 2019. Arsenic, uranium, fluoride and chromium (total) come from EPA’s file alone, which ends in 2019. Greenbriar Prairie Basse 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 March 4, 2013 to Oct. 15, 2018.
Testing your own tap
No lab Louisiana certifies is within 75 miles of the area Greenbriar Prairie Basse Water System serves on the state’s list. Some take samples by mail; the state’s page lists them all.
All 48 certified labs for LouisianaSources
- EPA UCMR 5 occurrence data, file of Oct. 15, 2026
- EPA SDWA bulk download (SDWIS federal data), 2026 Q3
- CDC Environmental Public Health Tracking Network, yearly averages Louisiana supplied to CDC, 2020 to 2022, read Oct. 8, 2026. TapBuff’s comparisons with EPA’s limits are its own, not CDC’s or Louisiana’s.
- EPA Six-Year Review 4 compliance monitoring data, 2012 to 2019, file of Feb. 5, 2024
- Limits and goals: each contaminant’s page, with its EPA source.
- How this page is built: methodology.
PWSID LA1097032. Rebuilt from EPA data on Oct. 18, 2026.
What to do next
- Read up on the 2 results above a lineWhat each one does to health, where it comes from, and the certification claim that addresses it.Start with Arsenic
- Get the utility’s own reportGreenbriar Prairie Basse Water System must send you a water quality report every year. It covers contaminants this page does not show, and has newer results than EPA’s national file for the ones here that come from it.How to read it
- Test your own tap for leadYour service line, solder and fixtures decide the lead at your faucet, not the utility’s average.Lead in your water: what to do
- Compare certified filtersWhat the filters certified for these results cost over five years, cartridges included.Compare five-year costs