Skip to content
TapBuff
ZIP

Caddo Lake 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
1,230 people
Connections
410
Water source
Groundwater
Based in
Karnack, TX
County
Harrison
Owner
Local government
The ZIP code it serves

75661

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), fluoride, nitrate, arsenic, chromium (total) and uranium: Texas’s own results, samples taken from Sept. 24, 2020 to Sept. 2, 2026, with EPA’s 2012 to 2019 file for earlier years.

Below EPA’s limits4

Total trihalomethanes (TTHM)

Forms or is added in treatment

Below EPA’s limits

37.1ppb

Highest yearly average, 2020 to 2026

2026, one sample: 35.4 ppb

Averaged by year, the highest was 37.1 ppb, in 2023, below EPA’s legal limit of 80 ppb. In 2026, the latest year on file, its one sample was 35.4 ppb. Earlier, from 2012 to 2019, EPA’s file shows a highest yearly average of 58.9 ppb, in 2019.

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

7.4ppb

Highest yearly average, 2020 to 2026

Averaged by year, the highest was 7.4 ppb, in 2026, below EPA’s legal limit of 60 ppb. That was also the latest year on file. Earlier, from 2012 to 2019, EPA’s file shows a highest yearly average of 11.4 ppb, in 2012.

What handles it

No certification claim covers this compound yet.

Fluoride

Forms or is added in treatment

Below EPA’s limits

0.19ppm

Highest yearly average, 2021 to 2025

2025, one sample: 0.071 ppm

Averaged by year, the highest was 0.19 ppm, in 2021, below EPA’s legal limit of 4.0 ppm. In 2025, the latest year on file, its one sample was 0.071 ppm. Earlier, from 2012 to 2019, EPA’s file shows a highest yearly average of 0.28 ppm, in 2012.

What handles it

Nitrate

Comes from the source

Below EPA’s limits

0.093ppm

Highest sample; found in 9 of 14

2026 average: 0.043 ppm

The highest sample, in 2021, was 0.093 ppm, below EPA’s legal limit of 10 ppm. In 2026, the latest year on file, its two samples averaged 0.043 ppm. Earlier, from 2012 to 2019, EPA’s file shows a highest sample of 0.13 ppm, in 2015.

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 4 monitoring or reporting violations: a sample missed, late or not reported.

What this report can’t tell you

  • Everything else. Total trihalomethanes (TTHM), haloacetic acids (HAA5), fluoride, nitrate, arsenic, chromium (total) and uranium results here are Texas’s own from 2020 on, with EPA’s national file for 2012 to 2019. Caddo Lake 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 Sept. 24, 2020 to Sept. 2, 2026.

Testing your own tap

Caddo Lake WSC’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.

The 3 labs Texas certifies closest to the area Caddo Lake WSC serves, in a straight line. Call first: certification is test by test, and not every lab takes samples from homeowners.

  • Southern Petroleum Laboratories (SPL), Inc. (FKA Ana-Lab Corporation)

    Kilgore, TX · about 44 miles

    Certified for bacteria, lead and copper

    (903) 984-0551

  • Environmental Monitoring Lab

    Winona, TX · about 55 miles

    Certified for bacteria

    (903) 877-9222

  • Northeast Texas Public Health District Laboratory

    Tyler, TX · about 69 miles

    Certified for bacteria

    (903) 535-0090

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

Sources

PWSID TX1020019. Rebuilt from EPA data on Oct. 18, 2026.

Also in Harrison County

All Texas utilities

What to do next