High Gabriel 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
- 492 people
- Connections
- 164
- Water source
- Groundwater
- Based in
- Cedar Park, TX
- County
- Williamson
- Owner
- Local government
The ZIP code it serves
The short answer
Nothing in EPA’s and Texas’s records for this utility is above a health goal. That covers nitrate, arsenic and other regulated chemicals, plus lead and copper, not everything. No health-based violations on file since 2016.
What was found
Fluoride, total trihalomethanes (TTHM), haloacetic acids (HAA5), nitrate, arsenic, chromium (total) and uranium: Texas’s own results, samples taken from May 27, 2020 to March 23, 2026, with EPA’s 2012 to 2019 file for earlier years.
Below EPA’s limits4
Fluoride
Forms or is added in treatment
0.76ppm
Highest yearly average, 2021 to 2024
Averaged by year, the highest was 0.76 ppm, in 2024, below EPA’s legal limit of 4.0 ppm. That was also the latest year on file. Earlier, from 2012 to 2019, EPA’s file shows a highest yearly average of 0.78 ppm, in 2015.
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
4.1ppb
Highest yearly average, 2022 to 2025
Averaged by year, the highest was 4.1 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 3.3 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
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.
What handles it
No certification claim covers this compound yet.
Nitrate
Comes from the source
0.14ppm
Highest sample; found in 4 of 7
2026: not found
The highest sample, in 2023, was 0.14 ppm, below EPA’s legal limit of 10 ppm. In 2026, the latest year on file, it wasn’t found in its one sample. Earlier, from 2012 to 2019, EPA’s file shows a highest sample of 0.04 ppm, in 2012.
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
Violations since 2016
No health-based violations on file with EPA since 2016. There are 21 monitoring or reporting violations: a sample missed, late or not reported.
What this report can’t tell you
Everything else. Fluoride, total trihalomethanes (TTHM), haloacetic acids (HAA5), nitrate, arsenic, chromium (total) and uranium results here are Texas’s own from 2020 on, with EPA’s national file for 2012 to 2019. High Gabriel 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 May 27, 2020 to March 23, 2026.
Testing your own tap
The 3 labs Texas certifies closest to the area High Gabriel WSC serves, in a straight line. Call first: certification is test by test, and not every lab takes samples from homeowners.
Integrity Testing, Inc.
Austin, TX · about 14 miles
Certified for lead and copper
Texas Department of State Health Services Laboratory Services Section
Austin, TX · about 19 miles
Certified for bacteria, lead and copper
Aqua-Tech Laboratories, Inc.
Austin, TX · about 29 miles
Certified for bacteria, lead and copper
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 TexasSources
- EPA UCMR 5 occurrence data, file of Oct. 15, 2026
- EPA SDWA bulk download (SDWIS federal data), 2026 Q3
- Texas Commission on Environmental Quality, Texas Drinking Water Viewer, results from Jan. 7, 2020 to Oct. 6, 2026, read Oct. 16, 2026
- EPA Six-Year Review 4 compliance monitoring data, 2012 to 2019, file of Feb. 5, 2024
- Certified labs: TCEQ, drinking water laboratories approved for public water system samples, read Oct. 10, 2026; distances from the Census 2020 ZIP code tabulation area gazetteer
- Limits and goals: each contaminant’s page, with its EPA source.
- How this page is built: methodology.
PWSID TX2460027. Rebuilt from EPA data on Oct. 18, 2026.
What to do next
- Nothing here is above a health goalIn EPA’s and Texas’s records for this utility. They don’t cover everything, which is why the next step matters.Every contaminant TapBuff tracks
- Get the utility’s own reportHigh Gabriel WSC must send you a water quality report every year. It covers contaminants this page does not show.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
- Decide if you want a filter at allA filter for taste or chlorine is a preference, not a need. The standards say what each kind can do.NSF/ANSI standards, decoded