Merrill Gardens Iris Canyon WS
What EPA’s and California’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
- 136 people
- Connections
- 4
- Water source
- Groundwater
- Based in
- Monterey, CA
- County
- Monterey
- Owner
- Private
- Hardness
- Varies by source
The ZIP code it serves
The short answer
1 result is above the limit’s level with no violation recorded, and 2 more are above the health goal. The worst: Total trihalomethanes (TTHM), above the limit’s level, no violation. No health-based violations on file since 2016.
What handles itWhat was found
Total trihalomethanes (TTHM), arsenic, uranium, haloacetic acids (HAA5), fluoride, nitrate and chromium (total): California’s own results, samples taken from Jan. 7, 2020 to June 23, 2026, with EPA’s 2012 to 2019 file for earlier years.
Above the limit’s level, no violation recorded1
Total trihalomethanes (TTHM)
Forms or is added in treatment
159ppb
Highest yearly average, 2020 to 2026
2026 average: 44 ppb
Averaged by year, the highest was 159 ppb, in 2021, about twice EPA’s legal limit of 80 ppb. Its highest single sample was 365 ppb. In 2026, the latest year on file, its two samples averaged 44 ppb. EPA judges this limit on running averages at each sampling point, and recorded no violation for total trihalomethanes (TTHM) at this utility since 2020. Results like these with no violation often include water sampled before treatment or blending; the utility’s annual report says what reaches the tap. Earlier, from 2012 to 2019, EPA’s file shows a highest yearly average of 67 ppb, in 2019.
What handles it
- NSF/ANSI 53 look for “Trihalomethanes (TTHM) Reduction”
- NSF/ANSI 58 look for “Trihalomethanes (TTHM) Reduction”
Above the health goal2
Arsenic
Comes from the source
1.8ppb
Highest yearly average, 2020 to 2023
2023 average: 0.82 ppb
Averaged by year, the highest was 1.8 ppb, in 2020: below EPA’s legal limit of 10 ppb, but above its health goal of zero. Its highest single sample was 2.9 ppb. In 2023, the latest year on file, its five samples averaged 0.82 ppb. Earlier, from 2012 to 2019, EPA’s file shows a highest yearly average of 1.6 ppb, in 2017.
What handles it
- NSF/ANSI 58 look for “Arsenic (Pentavalent)<=50 ppb Reduction”
- NSF/ANSI 53 look for “Arsenic (Pentavalent)<=50 ppb Reduction”
Uranium
Comes from the source
3.9ppb
Highest yearly average, 2022
Averaged by year, the highest was 3.9 ppb, in 2022: below EPA’s legal limit of 30 ppb, but above its health goal of zero. That is the only year on file.
What handles it
- NSF/ANSI 58 look for “Uranium”
Below EPA’s limits4
Haloacetic acids (HAA5)
Forms or is added in treatment
21.5ppb
Highest yearly average, 2020 to 2026
2026 average: 15.5 ppb
Averaged by year, the highest was 21.5 ppb, in 2025, below EPA’s legal limit of 60 ppb. Its highest single sample was 40 ppb. In 2026, the latest year on file, its two samples averaged 15.5 ppb. Earlier, from 2012 to 2019, EPA’s file shows a highest yearly average of 11 ppb, in 2019.
What handles it
No certification claim covers this compound yet.
Fluoride
Forms or is added in treatment
1.2ppm
Highest yearly average, 2020 to 2026
2026 average: 1.0 ppm
Averaged by year, the highest was 1.2 ppm, in 2024, below EPA’s legal limit of 4.0 ppm. Its highest single sample was 2.9 ppm. In 2026, the latest year on file, its six samples averaged 1.0 ppm. Earlier, from 2012 to 2019, EPA’s file shows a highest yearly average of 1.1 ppm, in 2017.
What handles it
- NSF/ANSI 58 look for “Fluoride Reduction”
- NSF/ANSI 53 look for “Fluoride”
Nitrate
Comes from the source
1.4ppm
Highest sample; found in 8 of 34
2025 average: 0.1 ppm
The highest sample, in 2021, was 1.4 ppm, below EPA’s legal limit of 10 ppm. In 2025, the latest year on file, its five samples averaged 0.1 ppm. Earlier, from 2012 to 2019, EPA’s file shows a highest sample of 0.7 ppm, in 2019.
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
2.2ppb
Highest yearly average, 2020 to 2023
2023: not found
Averaged by year, the highest was 2.2 ppb, in 2020, below EPA’s legal limit of 100 ppb. Its highest single sample was 3.5 ppb. In 2023, the latest year on file, it wasn’t found in any of its five samples. Earlier, from 2012 to 2019, EPA’s file shows a highest yearly average of 2.2 ppb, in 2017.
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
Claims: Trihalomethanes (TTHM) Reduction, Arsenic (Pentavalent)<=50 ppb Reduction
For: Total trihalomethanes (TTHM), Arsenic
Other certifiers’ wording: VOC Reduction; Arsenic (III) (50 ppb influent level)
- NSF/ANSI 58
Claims: Trihalomethanes (TTHM) Reduction, Arsenic (Pentavalent)<=50 ppb Reduction, Uranium
For: Total trihalomethanes (TTHM), Arsenic, Uranium
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
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: Total trihalomethanes (TTHM), 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: Total trihalomethanes (TTHM), Arsenic
Countertop reverse osmosis
- IAPMO listing:NSF/ANSI 42NSF/ANSI 53NSF/ANSI 58NSF/ANSI 401checked Oct. 4, 2026
Certified for: Total trihalomethanes (TTHM), Arsenic
Aquasana Clean Water Machine (AQ-CWM2)
Countertop
- WQA listing:NSF/ANSI 42NSF/ANSI 53NSF/ANSI 401checked Oct. 9, 2026
Certified for: Total trihalomethanes (TTHM)
Brita Hub Countertop Water Filter System (87340)
Countertop
- WQA listing:NSF/ANSI 42NSF/ANSI 53NSF/ANSI 401checked Oct. 9, 2026
- IAPMO listing:NSF/ANSI 53checked Oct. 9, 2026
Certified for: Total trihalomethanes (TTHM)
Hardness
Soft to very hard depending on the source, 57 to 223 mg/L (3.3 to 13 grains per gallon), across 6 sampling points, 2019 to 2023.
Hardness is calcium and magnesium. EPA sets no limit for it: it shows up as scale on fixtures and in water heaters, and as soap that won’t lather. USGS calls water above 60 mg/L moderately hard, above 120 hard and above 180 very hard.
Violations since 2016
No health-based violations on file with EPA since 2016. There are 2 monitoring or reporting violations: a sample missed, late or not reported.
What this report can’t tell you
Everything else. Total trihalomethanes (TTHM), arsenic, uranium, haloacetic acids (HAA5), fluoride, nitrate and chromium (total) results here are California’s own from 2020 on, with EPA’s national file for 2012 to 2019. Merrill Gardens Iris Canyon WS’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; California’s results run from Jan. 7, 2020 to June 23, 2026.
Testing your own tap
The 3 labs California certifies closest to the area Merrill Gardens Iris Canyon WS serves, in a straight line. Call first: certification is test by test, and not every lab takes samples from homeowners.
Monterey Bay Analytical Services, Inc.
Monterey, CA · about 1 mile
Certified for bacteria, nitrate, lead and copper, metals, minerals and other inorganics, radioactivity
Monterey County Consolidated Environmental Laboratory
Salinas, CA · about 14 miles
Certified for bacteria, nitrate, lead and copper, metals, minerals and other inorganics
Santa Cruz County - Health Services Agency - Environmental Health
Santa Cruz, CA · about 30 miles
Certified for bacteria
Sources
- EPA UCMR 5 occurrence data, file of Oct. 15, 2026
- EPA SDWA bulk download (SDWIS federal data), 2026 Q3
- California State Water Resources Control Board, Division of Drinking Water, results from Jan. 1, 2020 to July 17, 2026, read Oct. 8, 2026
- EPA Six-Year Review 4 compliance monitoring data, 2012 to 2019, file of Feb. 5, 2024
- Certified labs: California State Water Resources Control Board, ELAP accredited laboratories and their fields of accreditation, read Oct. 17, 2026; distances from the Census 2020 ZIP code tabulation area gazetteer
- Hardness: California State Water Resources Control Board, Division of Drinking Water, results from May 7, 2019 to Dec. 21, 2023, read Oct. 10, 2026
- Limits and goals: each contaminant’s page, with its EPA source.
- How this page is built: methodology.
PWSID CA2702816. Rebuilt from EPA data on Oct. 18, 2026.
What to do next
- Read up on the 3 results above a lineWhat each one does to health, where it comes from, and the certification claim that addresses it.Start with Total trihalomethanes (TTHM)
- Get the utility’s own reportMerrill Gardens Iris Canyon WS 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