Windmill Ranch Subdivision
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
- 756 people
- Connections
- 249
- Water source
- Surface water bought from another system
- Based in
- Austin, TX
- County
- Comal
- Owner
- Private
The ZIP code it serves
The short answer
1 result is above the health goal. The worst: Uranium, above the health goal. No health-based violations on file since 2016.
What handles itWhat was found
Uranium, total trihalomethanes (TTHM), haloacetic acids (HAA5), nitrate, fluoride, arsenic and chromium (total): Texas’s own results, samples taken from April 30, 2020 to Aug. 18, 2026, with EPA’s 2012 to 2019 file for earlier years.
Above the health goal1
Uranium
Comes from the source
1.4ppb
Highest yearly average, 2020 to 2023
2023: not found
Averaged by year, the highest was 1.4 ppb, in 2020: below EPA’s legal limit of 30 ppb, but above its health goal of zero. In 2023, the latest year on file, it wasn’t found in its one sample.
What handles it
- NSF/ANSI 58 look for “Uranium”
Below EPA’s limits4
Total trihalomethanes (TTHM)
Forms or is added in treatment
77.5ppb
Highest yearly average, 2020 to 2026
2026 average: 66.2 ppb
Averaged by year, the highest was 77.5 ppb, in 2025, below EPA’s legal limit of 80 ppb. Its highest single sample was 108 ppb. In 2026, the latest year on file, its three samples averaged 66.2 ppb. EPA recorded no violation for total trihalomethanes (TTHM) at this utility since 2020. Earlier, from 2012 to 2019, EPA’s file shows a highest yearly average of 55 ppb, in 2014.
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
24.9ppb
Highest yearly average, 2020 to 2026
2026 average: 16.2 ppb
Averaged by year, the highest was 24.9 ppb, in 2025, below EPA’s legal limit of 60 ppb. Its highest single sample was 36.7 ppb. In 2026, the latest year on file, its three samples averaged 16.2 ppb. Earlier, from 2012 to 2019, EPA’s file shows a highest yearly average of 14.8 ppb, in 2014.
What handles it
No certification claim covers this compound yet.
Nitrate
Comes from the source
1.6ppm
Highest sample; found in 14 of 14
2026 average: 0.39 ppm
The highest sample, in 2020, was 1.6 ppm, below EPA’s legal limit of 10 ppm. In 2026, the latest year on file, its two samples averaged 0.39 ppm. Earlier, from 2012 to 2019, EPA’s file shows a highest sample of 1.5 ppm, in 2017.
What handles it
- NSF/ANSI 58 look for “Nitrate/Nitrite Reduction”
- NSF/ANSI 53 look for “Nitrate/Nitrite (30 ppm challenge)”
Fluoride
Forms or is added in treatment
0.32ppm
Highest yearly average, 2020 to 2026
2026: not found
Averaged by year, the highest was 0.32 ppm, in 2023, below EPA’s legal limit of 4.0 ppm. In 2026, the latest year on file, it wasn’t found in any of its two samples. Earlier, from 2012 to 2019, EPA’s file shows a highest yearly average of 0.31 ppm, in 2014.
What handles it
- NSF/ANSI 58 look for “Fluoride Reduction”
- NSF/ANSI 53 look for “Fluoride”
3 compounds tested and not foundBelow the reporting level in every sample. Not found is not the same as zero.
- Arsenic
- 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 58
Claim: Uranium
For: Uranium
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
None of the filters TapBuff has checked so far carry these claims. Search the certifier listings for the claim above.
Compare five-year costsViolations since 2016
No health-based violations on file with EPA since 2016. There are 2 monitoring or reporting violations: a sample missed, late or not reported.
What this report can’t tell you
Everything else. Uranium, total trihalomethanes (TTHM), haloacetic acids (HAA5), nitrate, fluoride, arsenic and chromium (total) results here are Texas’s own from 2020 on, with EPA’s national file for 2012 to 2019. Windmill Ranch Subdivision’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 April 30, 2020 to Aug. 18, 2026.
Testing your own tap
The 3 labs Texas certifies closest to the area Windmill Ranch Subdivision serves, in a straight line. Call first: certification is test by test, and not every lab takes samples from homeowners.
Wallgren Environmental Services dba Pollution Control Services
Universal City, TX · about 25 miles
Certified for bacteria, lead and copper
Alamo Analytical Laboratories, Ltd.
San Antonio, TX · about 25 miles
Certified for lead and copper
Edwards Aquifer Research & Data Center, Texas State University
San Marcos, TX · about 26 miles
Certified for bacteria
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 TX0460221. Rebuilt from EPA data on Oct. 18, 2026.
What to do next
- Read up on UraniumWhat each one does to health, where it comes from, and the certification claim that addresses it.About Uranium
- Get the utility’s own reportWindmill Ranch Subdivision 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
- Compare certified filtersWhat the filters certified for these results cost over five years, cartridges included.Compare five-year costs