Town of Walsh
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
- 650 people
- Connections
- 355
- Water source
- Groundwater
- Based in
- Walsh, CO
- County
- Baca
- Owner
- Local government
The ZIP code it serves
The short answer
1 result is above EPA’s legal limit, and 3 more are above the health goal. The worst: Nitrate, above the legal limit. 19 health-based violations since 2016.
What handles itWhat was found
Lead and copper: EPA SDWIS monitoring periods ending 2016 to 2025.
Nitrate, uranium, arsenic, fluoride, total trihalomethanes (TTHM), haloacetic acids (HAA5) and chromium (total): Colorado’s own results, samples taken from Feb. 18, 2020 to Sept. 28, 2026, with EPA’s 2012 to 2019 file for earlier years.
Above the legal limit1
Nitrate
Comes from the source
12.5ppm
Highest sample; found in 44 of 44
2026 average: 10.7 ppm
From 2021 to 2026, 14 samples were above EPA’s legal limit of 10 ppm, the highest 12.5 ppm in 2024. The next sample at the same point, within 30 days, kept the average above the limit for six; two came back under and six have no follow-up sample on file within 30 days. In 2026, the latest year on file, its six samples averaged 10.7 ppm, above the limit. EPA recorded violations for nitrate at this utility in 2022, 2024, 2025 and 2026. Earlier, from 2012 to 2019, EPA’s file shows a highest sample of 11.3 ppm, in 2018, and EPA recorded violations in 2018 and 2019.
What handles it
- NSF/ANSI 58 look for “Nitrate/Nitrite Reduction”
- NSF/ANSI 53 look for “Nitrate/Nitrite (30 ppm challenge)”
Above the health goal3
Uranium
Comes from the source
12ppb
Highest yearly average, 2021 to 2025
2025, one sample: 10.6 ppb
Averaged by year, the highest was 12 ppb, in 2023: below EPA’s legal limit of 30 ppb, but above its health goal of zero. In 2025, the latest year on file, its one sample was 10.6 ppb. Earlier, from 2012 to 2019, EPA’s file shows a highest yearly average of 11.5 ppb, in 2013.
What handles it
- NSF/ANSI 58 look for “Uranium”
Arsenic
Comes from the source
4.0ppb
Highest yearly average, 2021 to 2025
2025, one sample: 3.0 ppb
Averaged by year, the highest was 4.0 ppb, in 2021: below EPA’s legal limit of 10 ppb, but above its health goal of zero. In 2025, the latest year on file, its one sample was 3.0 ppb. Earlier, from 2012 to 2019, EPA’s file shows a highest yearly average of 7.0 ppb, in 2019.
What handles it
- NSF/ANSI 58 look for “Arsenic (Pentavalent)<=50 ppb Reduction”
- NSF/ANSI 53 look for “Arsenic (Pentavalent)<=50 ppb Reduction”
Lead
Comes from pipes, often your own
1.0ppb
90th percentile, 2023 to 2025
In the latest period, 9 in 10 homes sampled were at or below 1.0 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 limits4
Fluoride
Forms or is added in treatment
0.89ppm
Highest yearly average, 2021 to 2025
Averaged by year, the highest was 0.89 ppm, in 2025, below EPA’s legal limit of 4.0 ppm. That was also the latest year on file. Earlier, from 2012 to 2019, EPA’s file shows a highest yearly average of 1.1 ppm, in 2016.
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
15ppb
Highest yearly average, 2020 to 2026
2026, one sample: 6.3 ppb
Averaged by year, the highest was 15 ppb, in 2024, below EPA’s legal limit of 80 ppb. In 2026, the latest year on file, its one sample was 6.3 ppb. Earlier, from 2012 to 2019, EPA’s file shows a highest yearly average of 12.4 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
3.7ppb
Highest yearly average, 2020 to 2026
2026, one sample: 2.5 ppb
Averaged by year, the highest was 3.7 ppb, in 2024, below EPA’s legal limit of 60 ppb. In 2026, the latest year on file, its one sample was 2.5 ppb. Earlier, from 2012 to 2019, EPA’s file shows a highest yearly average of 2.3 ppb, in 2016.
What handles it
No certification claim covers this compound yet.
Chromium (total)
Comes from the source
3.0ppb
Highest yearly average, 2021 to 2025
2025, one sample: 2.0 ppb
Averaged by year, the highest was 3.0 ppb, in 2021, 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 2019.
What handles it
- NSF/ANSI 58 look for “Chromium (Hexavalent) Reduction”
- NSF/ANSI 53 look for “Chromium Reduction”
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: Nitrate/Nitrite (30 ppm challenge), Arsenic (Pentavalent)<=50 ppb Reduction, Lead Reduction
For: Nitrate, Arsenic, Lead
Other certifiers’ wording: Arsenic (III) (50 ppb influent level)
- NSF/ANSI 58
Claims: Nitrate/Nitrite Reduction, Uranium, Arsenic (Pentavalent)<=50 ppb Reduction, Lead Reduction
For: Nitrate, Uranium, Arsenic, Lead
Other certifiers’ wording: Nitrate; Arsenic (Pentavalent)<=300 ppb Reduction; Arsenic (V) (300 ppb influent level)
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
Countertop reverse osmosis
- IAPMO listing:NSF/ANSI 42NSF/ANSI 53NSF/ANSI 58NSF/ANSI 401checked Oct. 4, 2026
Certified for: Nitrate, Arsenic, Lead
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: Nitrate, Arsenic, Lead
Culligan 10-Cup Pitcher with ZeroWater Technology (ZEROP10)
Pitcher
- IAPMO listing:NSF/ANSI 42NSF/ANSI 53NSF/ANSI 401checked Oct. 9, 2026
Certified for: Nitrate, 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: Arsenic, Lead
Violations since 2016
| Contaminant or rule | Type | Period | Measured | Status |
|---|---|---|---|---|
| Nitrate | The running average was above the legal limit.EPA: Maximum Contaminant Level Violation, Average | April 1, 2026 to June 30, 2026 | 11 MG/L | Archived |
| Combined Radium (-226 and -228) | The running average was above the legal limit.EPA: Maximum Contaminant Level Violation, Average | April 1, 2026 to June 30, 2026 | 6.0 PCI/L | Archived |
| Nitrate | The running average was above the legal limit.EPA: Maximum Contaminant Level Violation, Average | Oct. 1, 2025 to Dec. 31, 2025 | 11.3 MG/L | Archived |
| Combined Radium (-226 and -228) | The running average was above the legal limit.EPA: Maximum Contaminant Level Violation, Average | July 1, 2025 to Sept. 30, 2025 | 6.0 PCI/L | Archived |
| Combined Radium (-226 and -228) | The running average was above the legal limit.EPA: Maximum Contaminant Level Violation, Average | April 1, 2025 to June 30, 2025 | 6.0 PCI/L | Archived |
| Nitrate | The running average was above the legal limit.EPA: Maximum Contaminant Level Violation, Average | April 1, 2025 to June 30, 2025 | 11 MG/L | Archived |
| Combined Radium (-226 and -228) | The running average was above the legal limit.EPA: Maximum Contaminant Level Violation, Average | Jan. 1, 2025 to March 31, 2025 | 6.0 PCI/L | Archived |
| 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 | Archived |
| Nitrate | The running average was above the legal limit.EPA: Maximum Contaminant Level Violation, Average | July 1, 2024 to Sept. 30, 2024 | 11.2 MG/L | Resolved |
| Nitrate | The running average was above the legal limit.EPA: Maximum Contaminant Level Violation, Average | April 1, 2024 to June 30, 2024 | 12.4 MG/L | Resolved |
| Nitrate | The running average was above the legal limit.EPA: Maximum Contaminant Level Violation, Average | Oct. 1, 2022 to Dec. 31, 2022 | 10.8 MG/L | Resolved |
| Combined Radium (-226 and -228) | The running average was above the legal limit.EPA: Maximum Contaminant Level Violation, Average | April 1, 2022 to June 30, 2022 | 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, 2022 to March 31, 2022 | 6.5 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 | 6.9 PCI/L | Resolved |
| Combined Radium (-226 and -228) | The running average was above the legal limit.EPA: Maximum Contaminant Level Violation, Average | July 1, 2021 to Sept. 30, 2021 | 5.7 PCI/L | Resolved |
| Nitrate | The running average was above the legal limit.EPA: Maximum Contaminant Level Violation, Average | July 1, 2019 to Sept. 30, 2019 | 11 MG/L | Resolved |
| Nitrate | The running average was above the legal limit.EPA: Maximum Contaminant Level Violation, Average | July 1, 2018 to Sept. 30, 2018 | 11 MG/L | Resolved |
| Groundwater Rule | A significant problem found in a state inspection was not fixed on time.EPA: Failure To Address Deficiency | Jan. 12, 2018 | — | Resolved |
| Groundwater Rule | A significant problem found in a state inspection was not fixed on time.EPA: Failure To Address Deficiency | Jan. 12, 2018 | — | Resolved |
| Health-based violations only. Resolved and archived mean the utility returned to compliance or the state closed the record. 6 monitoring or reporting violations not shown. | ||||
What this report can’t tell you
Everything else. Nitrate, uranium, arsenic, fluoride, total trihalomethanes (TTHM), haloacetic acids (HAA5) and chromium (total) results here are Colorado’s own from 2020 on, with EPA’s national file for 2012 to 2019. Town of Walsh’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 Feb. 18, 2020 to Sept. 28, 2026.
Testing your own tap
No lab Colorado certifies is within 75 miles of the area Town of Walsh serves on the state’s list. Some take samples by mail; the state’s page lists them all.
All 54 certified labs for ColoradoSources
- 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
- Limits and goals: each contaminant’s page, with its EPA source.
- How this page is built: methodology.
PWSID CO0105900. 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 Nitrate
- Get the utility’s own reportTown of Walsh 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