Town of Merino
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
- 235 people
- Connections
- 157
- Water source
- Groundwater
- Based in
- Weldona, CO
- County
- Logan
- Owner
- Local government
The short answer
2 results are above the health goal. The worst: Uranium, above the health goal. 6 health-based violations since 2016.
What handles itWhat was found
Copper: EPA’s file records a utility’s copper only when it exceeds the action level. The last here was 2.6 ppm, for the period ending June 30, 2018. None since is on file, so it is not counted as a current finding.
Uranium, arsenic, nitrate, total trihalomethanes (TTHM), haloacetic acids (HAA5), fluoride and chromium (total): Colorado’s own results, samples taken from Feb. 19, 2020 to Nov. 4, 2025, with EPA’s 2012 to 2019 file for earlier years.
Above the health goal2
Uranium
Comes from the source
11.8ppb
Highest yearly average, 2020 to 2025
2025, one sample: 9.0 ppb
Averaged by year, the highest was 11.8 ppb, in 2020: below EPA’s legal limit of 30 ppb, but above its health goal of zero. Its highest single sample was 15 ppb. In 2025, the latest year on file, its one sample was 9.0 ppb. Earlier, from 2012 to 2019, EPA’s file shows a highest yearly average of 57.5 ppb, in 2017, and EPA recorded violations in 2012, 2014, 2015, 2016 and 2018.
What handles it
- NSF/ANSI 58 look for “Uranium”
Arsenic
Comes from the source
3.0ppb
Highest yearly average, 2020
Averaged by year, the highest was 3.0 ppb, in 2020: below EPA’s legal limit of 10 ppb, but above its health goal of zero. That is the only year on file. Earlier, from 2012 to 2019, EPA’s file shows a highest yearly average of 3.5 ppb, in 2013.
What handles it
- NSF/ANSI 58 look for “Arsenic (Pentavalent)<=50 ppb Reduction”
- NSF/ANSI 53 look for “Arsenic (Pentavalent)<=50 ppb Reduction”
Below EPA’s limits5
Nitrate
Comes from the source
4.4ppm
Highest sample; found in 6 of 6
2025, one sample: 3.2 ppm
The highest sample, in 2023, was 4.4 ppm, below EPA’s legal limit of 10 ppm. In 2025, the latest year on file, its one sample was 3.2 ppm. Earlier, from 2012 to 2019, EPA’s file shows a highest sample of 5.6 ppm, in 2017.
What handles it
- NSF/ANSI 58 look for “Nitrate/Nitrite Reduction”
- NSF/ANSI 53 look for “Nitrate/Nitrite (30 ppm challenge)”
Total trihalomethanes (TTHM)
Forms or is added in treatment
32.9ppb
Highest yearly average, 2020 to 2025
2025, one sample: 16.9 ppb
Averaged by year, the highest was 32.9 ppb, in 2022, below EPA’s legal limit of 80 ppb. In 2025, the latest year on file, its one sample was 16.9 ppb. Earlier, from 2012 to 2019, EPA’s file shows a highest yearly average of 90.1 ppb, in 2014, and EPA recorded violations in 2017 and 2018.
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
9.4ppb
Highest yearly average, 2020 to 2025
2025, one sample: 3.4 ppb
Averaged by year, the highest was 9.4 ppb, in 2020, below EPA’s legal limit of 60 ppb. Its highest single sample was 10.3 ppb. In 2025, the latest year on file, its one sample was 3.4 ppb. Earlier, from 2012 to 2019, EPA’s file shows a highest yearly average of 24.9 ppb, in 2017.
What handles it
No certification claim covers this compound yet.
Fluoride
Forms or is added in treatment
0.26ppm
Highest yearly average, 2020
Averaged by year, the highest was 0.26 ppm, in 2020, below EPA’s legal limit of 4.0 ppm. That is the only year on file. Earlier, from 2012 to 2019, EPA’s file shows a highest yearly average of 0.77 ppm, in 2016.
What handles it
- NSF/ANSI 58 look for “Fluoride Reduction”
- NSF/ANSI 53 look for “Fluoride”
Chromium (total)
Comes from the source
2.0ppb
Highest yearly average, 2020
Averaged by year, the highest was 2.0 ppb, in 2020, below EPA’s legal limit of 100 ppb. That is the only year on file. Earlier, from 2012 to 2019, EPA’s file shows a highest yearly average of 6.4 ppb, in 2013.
What handles it
- NSF/ANSI 58 look for “Chromium (Hexavalent) Reduction”
- NSF/ANSI 53 look for “Chromium Reduction”
One compound tested and not foundBelow the reporting level in every sample. Not found is not the same as zero.
- 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 53
Claim: Arsenic (Pentavalent)<=50 ppb Reduction
For: Arsenic
Other certifiers’ wording: Arsenic (III) (50 ppb influent level)
- NSF/ANSI 58
Claims: Uranium, Arsenic (Pentavalent)<=50 ppb Reduction
For: Uranium, Arsenic
Other certifiers’ wording: Arsenic (Pentavalent)<=300 ppb Reduction; Arsenic (V) (300 ppb influent level)
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
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: Arsenic
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: Arsenic
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
Violations since 2016
| Contaminant or rule | Type | Period | Measured | Status |
|---|---|---|---|---|
| Combined Uranium | The running average was above the legal limit.EPA: Maximum Contaminant Level Violation, Average | April 1, 2018 to June 30, 2018 | 35.8 UG/L | Resolved |
| TTHM | The running average was above the legal limit.EPA: Maximum Contaminant Level Violation, Average | April 1, 2018 to June 30, 2018 | 0.087 MG/L | Resolved |
| Combined Uranium | The running average was above the legal limit.EPA: Maximum Contaminant Level Violation, Average | Jan. 1, 2018 to March 31, 2018 | 43.7 UG/L | Resolved |
| TTHM | The running average was above the legal limit.EPA: Maximum Contaminant Level Violation, Average | Jan. 1, 2018 to March 31, 2018 | 0.1 MG/L | Resolved |
| TTHM | The running average was above the legal limit.EPA: Maximum Contaminant Level Violation, Average | Oct. 1, 2017 to Dec. 31, 2017 | 0.083 MG/L | Resolved |
| Combined Uranium | The running average was above the legal limit.EPA: Maximum Contaminant Level Violation, Average | April 1, 2016 to June 30, 2016 | 50.5 UG/L | Resolved |
| Health-based violations only. Resolved and archived mean the utility returned to compliance or the state closed the record. 15 monitoring or reporting violations not shown. | ||||
What this report can’t tell you
Everything else. Uranium, arsenic, nitrate, total trihalomethanes (TTHM), haloacetic acids (HAA5), fluoride and chromium (total) results here are Colorado’s own from 2020 on, with EPA’s national file for 2012 to 2019. Town of Merino’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. 19, 2020 to Nov. 4, 2025.
Testing your own tap
The 3 labs Colorado certifies closest to the area Town of Merino serves, in a straight line. Call first: certification is test by test, and not every lab takes samples from homeowners.
Northeast Colorado Health Dept.
Sterling, CO · about 10 miles
Certified for bacteria
Fort Morgan, City of
Ft. Morgan, CO · about 37 miles
Certified for bacteria
IEH-Warren Analytical Laboratory
Greeley, CO · about 69 miles
Certified for bacteria
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 CO0138025. Rebuilt from EPA data on Oct. 18, 2026.
What to do next
- Read up on the 2 results above a lineWhat each one does to health, where it comes from, and the certification claim that addresses it.Start with Uranium
- Get the utility’s own reportTown of Merino 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