Monte Vista Water Company
What EPA’s and CDC’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
- 150 people
- Connections
- 50
- Water source
- Groundwater
- Based in
- Douglas, AZ
- County
- Cochise
- Owner
- Private
The ZIP code it serves
The short answer
1 result is above EPA’s legal limit, and 1 more is above the health goal. The worst: Arsenic, above the legal limit. 12 health-based violations since 2016.
What handles itWhat was found
Lead and copper: EPA SDWIS monitoring periods ending 2010 to 2025.
Arsenic, nitrate, haloacetic acids (HAA5) and total trihalomethanes (TTHM): Arizona’s yearly averages per water system, as CDC’s Environmental Public Health Tracking Network publishes them, 2020 to 2023, with EPA’s 2012 to 2019 file for earlier years.
Fluoride and chromium (total): EPA’s compliance monitoring file, samples taken from Feb. 4, 2014 to Sept. 19, 2017. Newer results are in the utility’s annual water quality report.
Above the legal limit1
Arsenic
Comes from the source
11ppb
Highest yearly average, 2020 to 2023
Averaged by year, the highest was 11 ppb, in 2023, above EPA’s legal limit of 10 ppb. That was also the latest year on file. EPA recorded violations for arsenic at this utility in 2020, 2023 and 2024. Earlier, from 2012 to 2019, EPA’s file shows a highest yearly average of 11 ppb, in 2012, and EPA recorded violations in 2012, 2018 and 2019.
What handles it
- NSF/ANSI 58 look for “Arsenic (Pentavalent)<=50 ppb Reduction”
- NSF/ANSI 53 look for “Arsenic (Pentavalent)<=50 ppb Reduction”
Above the health goal1
Lead
Comes from pipes, often your own
4.6ppb
90th percentile, 2023 to 2025
In the latest period, 9 in 10 homes sampled were at or below 4.6 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 limits3
Fluoride
Forms or is added in treatment
1.8ppm
Highest yearly average, 2014 to 2017
2017, one sample: 0.85 ppm
Averaged by year, the highest was 1.8 ppm, in 2014, below EPA’s legal limit of 4.0 ppm. In 2017, the latest year on file, its one sample was 0.85 ppm.
What handles it
- NSF/ANSI 58 look for “Fluoride Reduction”
- NSF/ANSI 53 look for “Fluoride”
Nitrate
Comes from the source
2.1ppm
Highest yearly average, 2020 to 2023
2023 average: 1.7 ppm
Averaged by year, the highest was 2.1 ppm, in 2021, below EPA’s legal limit of 10 ppm. In 2023, the latest year on file, it averaged 1.7 ppm. Earlier, from 2012 to 2019, EPA’s file shows a highest sample of 2.4 ppm, in 2018.
What handles it
- NSF/ANSI 58 look for “Nitrate/Nitrite Reduction”
- NSF/ANSI 53 look for “Nitrate/Nitrite (30 ppm challenge)”
Chromium (total)
Comes from the source
3.7ppb
Highest yearly average, 2014 to 2017
2017, one sample: 3.7 ppb
Averaged by year, the highest was 3.7 ppb, in 2014, below EPA’s legal limit of 100 ppb. In 2017, the latest year on file, its one sample was 3.7 ppb.
What handles it
- NSF/ANSI 58 look for “Chromium (Hexavalent) Reduction”
- NSF/ANSI 53 look for “Chromium Reduction”
2 compounds tested and not foundBelow the reporting level in every sample. Not found is not the same as zero.
- Haloacetic acids (HAA5)
- Total trihalomethanes (TTHM)
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: Arsenic (Pentavalent)<=50 ppb Reduction, Lead Reduction
For: Arsenic, Lead
Other certifiers’ wording: Arsenic (III) (50 ppb influent level)
- NSF/ANSI 58
Claims: Arsenic (Pentavalent)<=50 ppb Reduction, Lead Reduction
For: Arsenic, Lead
Other certifiers’ wording: 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: 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: Arsenic, 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
Brita Tahoe Pitcher with Elite Filter (OB60, OB06)
Pitcher
- WQA listing:NSF/ANSI 42NSF/ANSI 53NSF/ANSI 401checked Oct. 13, 2026
- IAPMO listing:NSF/ANSI 53checked Oct. 13, 2026
Certified for: Lead
Violations since 2016
| Contaminant or rule | Type | Period | Measured | Status |
|---|---|---|---|---|
| Revised Total Coliform Rule | Coliform results required a check of the system, and the check or its fixes were not done on time.EPA: Treatment Technique, Level 1 Assessment (RTCR) | May 10, 2026 | — | Unaddressed |
| 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 | — | Resolved |
| Arsenic | The running average was above the legal limit.EPA: Maximum Contaminant Level Violation, Average | Jan. 1, 2024 to March 31, 2024 | 0.011 MG/L | Resolved |
| Arsenic | The running average was above the legal limit.EPA: Maximum Contaminant Level Violation, Average | Oct. 1, 2023 to Dec. 31, 2023 | 0.011 MG/L | Resolved |
| Arsenic | The running average was above the legal limit.EPA: Maximum Contaminant Level Violation, Average | July 1, 2020 to Sept. 30, 2020 | 0.012 MG/L | Resolved |
| Arsenic | The running average was above the legal limit.EPA: Maximum Contaminant Level Violation, Average | April 1, 2020 to June 30, 2020 | 0.011 MG/L | Resolved |
| Arsenic | The running average was above the legal limit.EPA: Maximum Contaminant Level Violation, Average | Jan. 1, 2020 to March 31, 2020 | 0.011 MG/L | Resolved |
| Arsenic | The running average was above the legal limit.EPA: Maximum Contaminant Level Violation, Average | Oct. 1, 2019 to Dec. 31, 2019 | 0.011 MG/L | Resolved |
| Arsenic | The running average was above the legal limit.EPA: Maximum Contaminant Level Violation, Average | April 1, 2019 to June 30, 2019 | 0.011 MG/L | Resolved |
| Arsenic | The running average was above the legal limit.EPA: Maximum Contaminant Level Violation, Average | Oct. 1, 2018 to Dec. 31, 2018 | 0.011 MG/L | Resolved |
| Groundwater Rule | A significant problem found in a state inspection was not fixed on time.EPA: Failure To Address Deficiency | Aug. 15, 2018 | — | Resolved |
| Arsenic | The running average was above the legal limit.EPA: Maximum Contaminant Level Violation, Average | July 1, 2018 to Sept. 30, 2018 | 0.011 MG/L | Resolved |
| Health-based violations only. Resolved and archived mean the utility returned to compliance or the state closed the record. 31 monitoring or reporting violations not shown. | ||||
What this report can’t tell you
Everything else. Arsenic, nitrate, haloacetic acids (HAA5) and total trihalomethanes (TTHM) results here are Arizona’s yearly averages as CDC publishes them, from 2020 on, with EPA’s national file for 2012 to 2019. Fluoride and chromium (total) come from EPA’s file alone, which ends in 2019. Monte Vista Water Company’s own annual report, which it must send you every year, has newer results for those and 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; CDC’s yearly averages for Arizona cover 2020 to 2023; EPA’s compliance samples are from Feb. 4, 2014 to Sept. 19, 2017.
Testing your own tap
No lab Arizona certifies is within 75 miles of the area Monte Vista Water Company serves on the state’s list. Some take samples by mail; the state’s page lists them all.
All 49 certified labs for ArizonaSources
- EPA UCMR 5 occurrence data, file of Oct. 15, 2026
- EPA SDWA bulk download (SDWIS federal data), 2026 Q3
- CDC Environmental Public Health Tracking Network, yearly averages Arizona supplied to CDC, 2020 to 2023, read Oct. 8, 2026. TapBuff’s comparisons with EPA’s limits are its own, not CDC’s or Arizona’s.
- 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 AZ0402043. 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 Arsenic
- Get the utility’s own reportMonte Vista Water Company must send you a water quality report every year. It covers contaminants this page does not show, and has newer results than EPA’s national file for the ones here that come from it.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