The Colony MUD 1b

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: 657 people
Connections: 220
Water source: Groundwater bought from another system
Based in: Austin, TX
County: Bastrop
Owner: Local government

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

Total trihalomethanes (TTHM), haloacetic acids (HAA5) and nitrate: Texas’s own results, samples taken from July 24, 2024 to July 8, 2026.

Below EPA’s limits3

Total trihalomethanes (TTHM)

Forms or is added in treatment

Below EPA’s limits

53.3ppb

Highest yearly average, 2024 to 2026

Averaged by year, the highest was 53.3 ppb, in 2026, below EPA’s legal limit of 80 ppb. Its highest single sample was 67 ppb. That was also the latest year on file.

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

Below EPA’s limits

5.5ppb

Highest yearly average, 2024 to 2026

2026 average: 4.3 ppb

Averaged by year, the highest was 5.5 ppb, in 2024, below EPA’s legal limit of 60 ppb. Its highest single sample was 6.0 ppb. In 2026, the latest year on file, its two samples averaged 4.3 ppb.

What handles it

No certification claim covers this compound yet.

Nitrate

Comes from the source

Below EPA’s limits

0.11ppm

Highest sample; found in 1 of 3

2026: not found

The highest sample, in 2024, was 0.11 ppm, below EPA’s legal limit of 10 ppm. In 2026, the latest year on file, it wasn’t found in its one sample.

What handles it

NSF/ANSI 58 look for “Nitrate/Nitrite Reduction”
NSF/ANSI 53 look for “Nitrate/Nitrite (30 ppm challenge)”

One compound tested and not foundBelow the reporting level in every sample. Not found is not the same as zero.

Lead

Violations since 2016

No health-based violations on file with EPA since 2016. There is 1 monitoring or reporting violation: a sample missed, late or not reported.

What this report can’t tell you

Everything else. Total trihalomethanes (TTHM), haloacetic acids (HAA5) and nitrate results here are Texas’s own from 2024 on, with EPA’s national file for 2012 to 2019. The Colony MUD 1b’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 July 24, 2024 to July 8, 2026.

Testing your own tap

The Colony MUD 1b’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 Texas certifies.

No lab Texas certifies is within 75 miles of the area The Colony MUD 1b serves on the state’s list. Some take samples by mail; the state’s page lists them all.

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 Texas