Slc 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
- 1,749 people
- Connections
- 632
- Water source
- Surface water
- Based in
- Groesbeck, TX
- County
- Limestone
- Owner
- Local government
The short answer
3 results are above EPA’s legal limit, and 1 more is above the health goal. The worst: Copper, above the action level. 38 health-based violations since 2016.
What handles itWhat was found
Lead and copper: EPA SDWIS monitoring periods ending 2022 to 2026.
Total trihalomethanes (TTHM), haloacetic acids (HAA5), nitrate, fluoride, arsenic, chromium (total) and uranium: Texas’s own results, samples taken from Feb. 25, 2020 to July 20, 2026, with EPA’s 2012 to 2019 file for earlier years.
Above the legal limit3
Copper
Comes from pipes, often your own
2.3ppm
90th percentile, 2026
In the latest period, 9 in 10 homes sampled were at or below 2.3 ppm, above EPA’s action level of 1.3 ppm.
What handles it
- NSF/ANSI 53 look for “Copper Reduction”
- NSF/ANSI 58 look for “Copper Reduction”
Total trihalomethanes (TTHM)
Forms or is added in treatment
139ppb
Highest yearly average, 2020 to 2026
2026 average: 74.6 ppb
Averaged by year, the highest was 139 ppb, in 2023, above EPA’s legal limit of 80 ppb. Its highest single sample was 265 ppb. In 2026, the latest year on file, its six samples averaged 74.6 ppb. EPA recorded violations for total trihalomethanes (TTHM) at this utility in 2022, 2023, 2024, 2025 and 2026. Earlier, from 2012 to 2019, EPA’s file shows a highest yearly average of 147 ppb, in 2012, and EPA recorded violations in 2012, 2013, 2015, 2016, 2017, 2018 and 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
74.8ppb
Highest yearly average, 2020 to 2026
2026 average: 33.9 ppb
Averaged by year, the highest was 74.8 ppb, in 2024, above EPA’s legal limit of 60 ppb. Its highest single sample was 179 ppb. In 2026, the latest year on file, its six samples averaged 33.9 ppb. EPA recorded a violation for haloacetic acids (HAA5) at this utility in 2024. Earlier, from 2012 to 2019, EPA’s file shows a highest yearly average of 92.7 ppb, in 2012, and EPA recorded violations in 2012, 2013, 2015 and 2016.
What handles it
No certification claim covers this compound yet.
Above the health goal1
Lead
Comes from pipes, often your own
8.0ppb
90th percentile, 2026
In the latest period, 9 in 10 homes sampled were at or below 8.0 ppb, below EPA’s action level of 15 ppb. The action level drops to 10 ppb on Nov. 1, 2027. EPA’s health goal for lead is zero.
What handles it
- NSF/ANSI 53 look for “Lead Reduction”
- NSF/ANSI 58 look for “Lead Reduction”
Below EPA’s limits2
Nitrate
Comes from the source
0.48ppm
Highest sample; found in 7 of 7
2026, one sample: 0.066 ppm
The highest sample, in 2020, was 0.48 ppm, below EPA’s legal limit of 10 ppm. In 2026, the latest year on file, its one sample was 0.066 ppm. Earlier, from 2012 to 2019, EPA’s file shows a highest sample of 0.42 ppm, in 2019.
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
0.12ppm
Highest yearly average, 2020 to 2026
2026, one sample: 0.098 ppm
Averaged by year, the highest was 0.12 ppm, in 2025, below EPA’s legal limit of 4.0 ppm. In 2026, the latest year on file, its one sample was 0.098 ppm. Earlier, from 2012 to 2019, EPA’s file shows a highest yearly average of 0.39 ppm, in 2012.
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)
- Uranium
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
Claims: Copper Reduction, Trihalomethanes (TTHM) Reduction, Lead Reduction
For: Copper, Total trihalomethanes (TTHM), Lead
Other certifiers’ wording: VOC Reduction
- NSF/ANSI 58
Claims: Copper Reduction, Trihalomethanes (TTHM) Reduction, Lead Reduction
For: Copper, Total trihalomethanes (TTHM), Lead
At the tap, or for the whole house?
Lead and copper usually come from pipes and fixtures inside or near your home. A whole-house system sits where water enters, so it cannot catch what your own plumbing adds after it. For those, the filter that counts is the one at the tap. 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
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: Copper, Total trihalomethanes (TTHM), Lead
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: Copper, Total trihalomethanes (TTHM), Lead
Countertop reverse osmosis
- IAPMO listing:NSF/ANSI 42NSF/ANSI 53NSF/ANSI 58NSF/ANSI 401checked Oct. 4, 2026
Certified for: Copper, Total trihalomethanes (TTHM), Lead
PUR PLUS 11-Cup Pitcher (PPT111W)
Pitcher
- NSF listing:NSF/ANSI 42NSF/ANSI 53NSF/ANSI 401checked Oct. 4, 2026
- WQA listing:NSF/ANSI 42NSF/ANSI 53NSF/ANSI 401checked Oct. 4, 2026
- IAPMO listing:NSF/ANSI 42NSF/ANSI 53NSF/ANSI 401checked Oct. 4, 2026
Certified for: Copper, Lead
Culligan 10-Cup Pitcher with ZeroWater Technology (ZEROP10)
Pitcher
- IAPMO listing:NSF/ANSI 42NSF/ANSI 53NSF/ANSI 401checked Oct. 9, 2026
Certified for: Copper, Lead
Violations since 2016
| Contaminant or rule | Type | Period | Measured | Status |
|---|---|---|---|---|
| TTHM | The running average was above the legal limit.EPA: Maximum Contaminant Level Violation, Average | April 1, 2026 to June 30, 2026 | 0.081 MG/L | Archived |
| TTHM | The running average was above the legal limit.EPA: Maximum Contaminant Level Violation, Average | Jan. 1, 2025 to March 31, 2025 | 0.089 MG/L | Resolved |
| 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 | — | Unaddressed |
| TTHM | The running average was above the legal limit.EPA: Maximum Contaminant Level Violation, Average | Oct. 1, 2024 to Dec. 31, 2024 | 0.11 MG/L | Resolved |
| Total Haloacetic Acids (HAA5) | The running average was above the legal limit.EPA: Maximum Contaminant Level Violation, Average | Oct. 1, 2024 to Dec. 31, 2024 | 0.081 MG/L | Resolved |
| TTHM | The running average was above the legal limit.EPA: Maximum Contaminant Level Violation, Average | July 1, 2024 to Sept. 30, 2024 | 0.14 MG/L | Resolved |
| Total Haloacetic Acids (HAA5) | The running average was above the legal limit.EPA: Maximum Contaminant Level Violation, Average | July 1, 2024 to Sept. 30, 2024 | 0.074 MG/L | Resolved |
| TTHM | The running average was above the legal limit.EPA: Maximum Contaminant Level Violation, Average | April 1, 2024 to June 30, 2024 | 0.16 MG/L | Resolved |
| Total Haloacetic Acids (HAA5) | The running average was above the legal limit.EPA: Maximum Contaminant Level Violation, Average | April 1, 2024 to June 30, 2024 | 0.07 MG/L | Resolved |
| TTHM | The running average was above the legal limit.EPA: Maximum Contaminant Level Violation, Average | Jan. 1, 2024 to March 31, 2024 | 0.16 MG/L | Resolved |
| Interim Enhanced Surface Water Treatment Rule | Too many readings in a month showed cloudiness above the filtration standard.EPA: Monthly Turbidity Exceed (Enhanced SWTR) | Nov. 1, 2023 to Nov. 30, 2023 | — | Resolved |
| TTHM | The running average was above the legal limit.EPA: Maximum Contaminant Level Violation, Average | Oct. 1, 2023 to Dec. 31, 2023 | 0.15 MG/L | Resolved |
| TTHM | The running average was above the legal limit.EPA: Maximum Contaminant Level Violation, Average | Oct. 1, 2023 to Dec. 31, 2023 | 0.13 MG/L | Resolved |
| TTHM | The running average was above the legal limit.EPA: Maximum Contaminant Level Violation, Average | July 1, 2023 to Sept. 30, 2023 | 0.17 MG/L | Resolved |
| Lead and Copper Rule | A required study or plan for corrosion control was not done on time.EPA: OCCT/SOWT Study/Recommendation | April 1, 2023 | — | Addressed |
| Interim Enhanced Surface Water Treatment Rule | Too many readings in a month showed cloudiness above the filtration standard.EPA: Monthly Turbidity Exceed (Enhanced SWTR) | April 1, 2023 to April 30, 2023 | — | Resolved |
| TTHM | The running average was above the legal limit.EPA: Maximum Contaminant Level Violation, Average | April 1, 2023 to June 30, 2023 | 0.13 MG/L | Resolved |
| Interim Enhanced Surface Water Treatment Rule | Too many readings in a month showed cloudiness above the filtration standard.EPA: Monthly Turbidity Exceed (Enhanced SWTR) | Feb. 1, 2023 to Feb. 28, 2023 | — | Resolved |
| Interim Enhanced Surface Water Treatment Rule | One cloudiness reading was above the maximum allowed.EPA: Single Turbidity Exceed (Enhanced SWTR) | Feb. 1, 2023 to Feb. 28, 2023 | — | Resolved |
| TTHM | The running average was above the legal limit.EPA: Maximum Contaminant Level Violation, Average | Jan. 1, 2023 to March 31, 2023 | 0.11 MG/L | Resolved |
| TTHM | The running average was above the legal limit.EPA: Maximum Contaminant Level Violation, Average | Oct. 1, 2022 to Dec. 31, 2022 | 0.087 MG/L | Resolved |
| Interim Enhanced Surface Water Treatment Rule | Too many readings in a month showed cloudiness above the filtration standard.EPA: Monthly Turbidity Exceed (Enhanced SWTR) | Sept. 1, 2022 to Sept. 30, 2022 | — | Resolved |
| Interim Enhanced Surface Water Treatment Rule | Too many readings in a month showed cloudiness above the filtration standard.EPA: Monthly Turbidity Exceed (Enhanced SWTR) | July 1, 2022 to July 31, 2022 | — | Resolved |
| Interim Enhanced Surface Water Treatment Rule | Too many readings in a month showed cloudiness above the filtration standard.EPA: Monthly Turbidity Exceed (Enhanced SWTR) | April 1, 2021 to April 30, 2021 | — | Resolved |
| Lead and Copper Rule | OCCT/SOWT Treatment Installation/Demonstration | April 10, 2020 | — | Unaddressed |
| Lead and Copper Rule | Required information about lead was not given to customers.EPA: Public Education | Dec. 1, 2019 | — | Resolved |
| TTHM | The running average was above the legal limit.EPA: Maximum Contaminant Level Violation, Average | July 1, 2019 to Sept. 30, 2019 | 0.093 MG/L | Resolved |
| TTHM | The running average was above the legal limit.EPA: Maximum Contaminant Level Violation, Average | Oct. 1, 2018 to Dec. 31, 2018 | 0.082 MG/L | Resolved |
| TTHM | The running average was above the legal limit.EPA: Maximum Contaminant Level Violation, Average | Jan. 1, 2017 to March 31, 2017 | 0.099 MG/L | Resolved |
| Lead and Copper Rule | Required information about lead was not given to customers.EPA: Public Education | Dec. 1, 2016 | — | Resolved |
| TTHM | The running average was above the legal limit.EPA: Maximum Contaminant Level Violation, Average | Oct. 1, 2016 to Dec. 31, 2016 | 0.096 MG/L | Resolved |
| TTHM | The running average was above the legal limit.EPA: Maximum Contaminant Level Violation, Average | Oct. 1, 2016 to Dec. 31, 2016 | 0.11 MG/L | Resolved |
| Total Haloacetic Acids (HAA5) | The running average was above the legal limit.EPA: Maximum Contaminant Level Violation, Average | July 1, 2016 to Sept. 30, 2016 | 0.076 MG/L | Resolved |
| TTHM | The running average was above the legal limit.EPA: Maximum Contaminant Level Violation, Average | July 1, 2016 to Sept. 30, 2016 | 0.12 MG/L | Resolved |
| Total Haloacetic Acids (HAA5) | The running average was above the legal limit.EPA: Maximum Contaminant Level Violation, Average | April 1, 2016 to June 30, 2016 | 0.081 MG/L | Resolved |
| TTHM | The running average was above the legal limit.EPA: Maximum Contaminant Level Violation, Average | April 1, 2016 to June 30, 2016 | 0.13 MG/L | Resolved |
| TTHM | The running average was above the legal limit.EPA: Maximum Contaminant Level Violation, Average | Jan. 1, 2016 to March 31, 2016 | 0.098 MG/L | Resolved |
| Total Haloacetic Acids (HAA5) | The running average was above the legal limit.EPA: Maximum Contaminant Level Violation, Average | Jan. 1, 2016 to March 31, 2016 | 0.083 MG/L | Resolved |
| Health-based violations only. Resolved and archived mean the utility returned to compliance or the state closed the record. 129 monitoring or reporting violations not shown. | ||||
What this report can’t tell you
Everything else. Total trihalomethanes (TTHM), haloacetic acids (HAA5), nitrate, fluoride, arsenic, chromium (total) and uranium results here are Texas’s own from 2020 on, with EPA’s national file for 2012 to 2019. Slc 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 Feb. 25, 2020 to July 20, 2026.
Testing your own tap
The 3 labs Texas certifies closest to the area Slc WSC serves, in a straight line. Call first: certification is test by test, and not every lab takes samples from homeowners.
Bio-Chem Lab, Inc.
West, TX · about 42 miles
Certified for bacteria, lead and copper
Aqua-Tech Laboratories, Inc.
Bryan, TX · about 53 miles
Certified for bacteria, lead and copper
Environmental Monitoring Lab
Hillsboro, TX · about 55 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 TX1470031. Rebuilt from EPA data on Oct. 18, 2026.
What to do next
- Read up on the 4 results above a lineWhat each one does to health, where it comes from, and the certification claim that addresses it.Start with Copper
- Get the utility’s own reportSlc 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
- Compare certified filtersWhat the filters certified for these results cost over five years, cartridges included.Compare five-year costs