Louviers WSD
What EPA’s and Colorado’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
- 238 people
- Connections
- 113
- Water source
- Groundwater
- Based in
- Castle Rock, CO
- County
- Douglas
- Owner
- Private
The ZIP code it serves
The short answer
1 result is above the health goal. The worst: Uranium, above the health goal. 18 health-based violations since 2016.
What handles itWhat was found
Uranium, fluoride, total trihalomethanes (TTHM), chromium (total), nitrate, arsenic and haloacetic acids (HAA5): Colorado’s own results, samples taken from April 8, 2020 to Aug. 3, 2026, with EPA’s 2012 to 2019 file for earlier years.
Above the health goal1
Uranium
Comes from the source
1.6ppb
Highest yearly average, 2021 to 2025
Averaged by year, the highest was 1.6 ppb, in 2025: below EPA’s legal limit of 30 ppb, but above its health goal of zero. That was also the latest year on file. Earlier, from 2012 to 2019, EPA’s file shows a highest yearly average of 2.0 ppb, in 2017.
What handles it
- NSF/ANSI 58 look for “Uranium”
Below EPA’s limits4
Fluoride
Forms or is added in treatment
1.4ppm
Highest yearly average, 2022 to 2025
2025, one sample: 1.3 ppm
Averaged by year, the highest was 1.4 ppm, in 2022, below EPA’s legal limit of 4.0 ppm. In 2025, the latest year on file, its one sample was 1.3 ppm. Earlier, from 2012 to 2019, EPA’s file shows a highest yearly average of 1.6 ppm, in 2014.
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
4.2ppb
Highest yearly average, 2020 to 2026
2026: not found
Averaged by year, the highest was 4.2 ppb, in 2023, below EPA’s legal limit of 80 ppb. In 2026, the latest year on file, it wasn’t found in its one sample.
What handles it
- NSF/ANSI 53 look for “Trihalomethanes (TTHM) Reduction”
- NSF/ANSI 58 look for “Trihalomethanes (TTHM) Reduction”
Chromium (total)
Comes from the source
3.0ppb
Highest yearly average, 2022 to 2025
2025, one sample: 2.0 ppb
Averaged by year, the highest was 3.0 ppb, in 2022, below EPA’s legal limit of 100 ppb. In 2025, the latest year on file, its one sample was 2.0 ppb. Earlier, from 2012 to 2019, EPA’s file shows a highest yearly average of 3.0 ppb, in 2017.
What handles it
- NSF/ANSI 58 look for “Chromium (Hexavalent) Reduction”
- NSF/ANSI 53 look for “Chromium Reduction”
Nitrate
Comes from the source
0.2ppm
Highest sample; found in 1 of 7
2026, one sample: 0.2 ppm
The highest sample, in 2026, was 0.2 ppm, below EPA’s legal limit of 10 ppm. That was also the latest year on file, and its one sample was 0.2 ppm. Earlier, from 2012 to 2019, EPA’s file shows a highest sample of 0.6 ppm, in 2017.
What handles it
- NSF/ANSI 58 look for “Nitrate/Nitrite Reduction”
- NSF/ANSI 53 look for “Nitrate/Nitrite (30 ppm challenge)”
3 compounds tested and not foundBelow the reporting level in every sample. Not found is not the same as zero.
- Arsenic
- Haloacetic acids (HAA5)
- 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
| Contaminant or rule | Type | Period | Measured | Status |
|---|---|---|---|---|
| Combined Radium (-226 and -228) | The running average was above the legal limit.EPA: Maximum Contaminant Level Violation, Average | Oct. 1, 2024 to Dec. 31, 2024 | 6.0 PCI/L | Resolved |
| Combined Radium (-226 and -228) | The running average was above the legal limit.EPA: Maximum Contaminant Level Violation, Average | July 1, 2024 to Sept. 30, 2024 | 6.0 PCI/L | Resolved |
| Combined Radium (-226 and -228) | The running average was above the legal limit.EPA: Maximum Contaminant Level Violation, Average | April 1, 2024 to June 30, 2024 | 7.0 PCI/L | Resolved |
| Combined Radium (-226 and -228) | The running average was above the legal limit.EPA: Maximum Contaminant Level Violation, Average | Jan. 1, 2024 to March 31, 2024 | 7.2 PCI/L | Resolved |
| Combined Radium (-226 and -228) | The running average was above the legal limit.EPA: Maximum Contaminant Level Violation, Average | Oct. 1, 2023 to Dec. 31, 2023 | 7.0 PCI/L | Resolved |
| Combined Radium (-226 and -228) | The running average was above the legal limit.EPA: Maximum Contaminant Level Violation, Average | July 1, 2023 to Sept. 30, 2023 | 6.3 PCI/L | Resolved |
| Combined Radium (-226 and -228) | The running average was above the legal limit.EPA: Maximum Contaminant Level Violation, Average | April 1, 2023 to June 30, 2023 | 6.0 PCI/L | Resolved |
| Combined Radium (-226 and -228) | The running average was above the legal limit.EPA: Maximum Contaminant Level Violation, Average | Oct. 1, 2021 to Dec. 31, 2021 | 6.0 PCI/L | Resolved |
| Combined Radium (-226 and -228) | The running average was above the legal limit.EPA: Maximum Contaminant Level Violation, Average | Jan. 1, 2021 to March 31, 2021 | 6.0 PCI/L | Resolved |
| Combined Radium (-226 and -228) | The running average was above the legal limit.EPA: Maximum Contaminant Level Violation, Average | Oct. 1, 2020 to Dec. 31, 2020 | 6.0 PCI/L | Resolved |
| Combined Radium (-226 and -228) | The running average was above the legal limit.EPA: Maximum Contaminant Level Violation, Average | July 1, 2020 to Sept. 30, 2020 | 6.0 PCI/L | Resolved |
| Combined Radium (-226 and -228) | The running average was above the legal limit.EPA: Maximum Contaminant Level Violation, Average | April 1, 2020 to June 30, 2020 | 7.0 PCI/L | Resolved |
| Combined Radium (-226 and -228) | The running average was above the legal limit.EPA: Maximum Contaminant Level Violation, Average | Jan. 1, 2020 to March 31, 2020 | 7.0 PCI/L | Resolved |
| Combined Radium (-226 and -228) | The running average was above the legal limit.EPA: Maximum Contaminant Level Violation, Average | Oct. 1, 2019 to Dec. 31, 2019 | 8.0 PCI/L | Resolved |
| Combined Radium (-226 and -228) | The running average was above the legal limit.EPA: Maximum Contaminant Level Violation, Average | July 1, 2019 to Sept. 30, 2019 | 8.2 PCI/L | Resolved |
| Combined Radium (-226 and -228) | The running average was above the legal limit.EPA: Maximum Contaminant Level Violation, Average | April 1, 2019 to June 30, 2019 | 7.0 PCI/L | Resolved |
| Combined Radium (-226 and -228) | The running average was above the legal limit.EPA: Maximum Contaminant Level Violation, Average | Jan. 1, 2019 to March 31, 2019 | 7.0 PCI/L | Resolved |
| Combined Radium (-226 and -228) | The running average was above the legal limit.EPA: Maximum Contaminant Level Violation, Average | Oct. 1, 2018 to Dec. 31, 2018 | 5.9 PCI/L | Resolved |
| Health-based violations only. Resolved and archived mean the utility returned to compliance or the state closed the record. 13 monitoring or reporting violations not shown. | ||||
What this report can’t tell you
Everything else. Uranium, fluoride, total trihalomethanes (TTHM), chromium (total), nitrate, arsenic and haloacetic acids (HAA5) results here are Colorado’s own from 2020 on, with EPA’s national file for 2012 to 2019. Louviers WSD’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; Colorado’s results run from April 8, 2020 to Aug. 3, 2026.
Testing your own tap
The 3 labs Colorado certifies closest to the area Louviers WSD serves, in a straight line. Call first: certification is test by test, and not every lab takes samples from homeowners.
Colorado Department of Health & Environment
Denver, CO · about 18 miles
Certified for bacteria
SGS North America, Inc. - Wheat Ridge
Wheat Ridge, CO · about 21 miles
Certified for nitrate, lead and copper, metals, minerals and other inorganics, organic chemicals, disinfection byproducts, radioactivity
Eurofins Denver
Arvada, CO · about 23 miles
Certified for nitrate, minerals and other inorganics, organic chemicals, PFAS
Sources
- EPA UCMR 5 occurrence data, file of Oct. 15, 2026
- EPA SDWA bulk download (SDWIS federal data), 2026 Q3
- Colorado Department of Public Health and Environment, Water Quality Control Division, results from Jan. 3, 2020 to Oct. 6, 2026, read Oct. 17, 2026
- EPA Six-Year Review 4 compliance monitoring data, 2012 to 2019, file of Feb. 5, 2024
- Certified labs: CDPHE certified drinking water laboratories, read Oct. 16, 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 CO0118035. 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 reportLouviers WSD 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