Skip to content
TapBuff

Moraga Heights Mutual Water

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
66 people
Connections
20
Water source
Groundwater
Based in
Canyon, CA
County
Contra Costa
Owner
Private
Hardness
Varies by source
The ZIP code it serves

94516

The short answer

Nothing in EPA’s and California’s records for this utility is above a health goal. That covers nitrate, arsenic and other regulated chemicals, plus lead and copper, not everything. No health-based violations on file since 2016.

What was found

Fluoride, nitrate, arsenic and chromium (total): California’s own results, samples taken from July 8, 2020 to Feb. 3, 2026, with EPA’s 2012 to 2019 file for earlier years.

Total trihalomethanes (TTHM): EPA’s compliance monitoring file, samples taken from Feb. 16, 2016 to Feb. 16, 2016. Newer results are in the utility’s annual water quality report.

Below EPA’s limits2

Fluoride

Forms or is added in treatment

Below EPA’s limits

0.32ppm

Highest yearly average, 2020 to 2023

2023, one sample: 0.18 ppm

Averaged by year, the highest was 0.32 ppm, in 2020, below EPA’s legal limit of 4.0 ppm. In 2023, the latest year on file, its one sample was 0.18 ppm. Earlier, from 2012 to 2019, EPA’s file shows a highest yearly average of 0.33 ppm, in 2014.

What handles it

Nitrate

Comes from the source

Below EPA’s limits

0.47ppm

Highest sample; found in 1 of 4

2026: not found

The highest sample, in 2023, was 0.47 ppm, below EPA’s legal limit of 10 ppm. In 2026, the latest year on file, it wasn’t found in its one sample. Earlier, from 2012 to 2019, EPA’s file shows a highest sample of 0.32 ppm, in 2012.

What handles it

  • NSF/ANSI 58 look for “Nitrate/Nitrite Reduction”
  • NSF/ANSI 53 look for “Nitrate/Nitrite (30 ppm challenge)”
4 compounds tested and not foundBelow the reporting level in every sample. Not found is not the same as zero.
  • Arsenic
  • Chromium (total)
  • Lead
  • Total trihalomethanes (TTHM)

Hardness

Moderately hard to very hard depending on the source, 98 to 487 mg/L (5.7 to 28.5 grains per gallon), across 2 sampling points, 2020 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.

What this report can’t tell you

  • Everything else. Fluoride, nitrate, arsenic and chromium (total) results here are California’s own from 2020 on, with EPA’s national file for 2012 to 2019. Total trihalomethanes (TTHM) comes from EPA’s file alone, which ends in 2019. Moraga Heights Mutual Water’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; California’s results run from July 8, 2020 to Feb. 3, 2026; EPA’s compliance samples are from Feb. 16, 2016 to Feb. 16, 2016.

Testing your own tap

Moraga Heights Mutual Water’s results are for the water it sends out. What your own service line, solder and fixtures add shows up only in a test of your tap, by a lab California certifies.

The 3 labs California certifies closest to the area Moraga Heights Mutual Water serves, in a straight line. Call first: certification is test by test, and not every lab takes samples from homeowners.

  • Eurofins Built Environment Testing West, LLC

    Emeryville, CA · about 7 miles

    Certified for lead and copper

    (510) 653-0824

  • EMSL Analytical Inc.

    San Leandro, CA · about 8 miles

    Certified for asbestos

    (510) 895-3675

  • Asbestos TEM Laboratories, Inc

    Oakland, CA · about 8 miles

    Certified for asbestos

    (510) 704-8930

All 145 certified labs for California

Sources

PWSID CA0707585. Rebuilt from EPA data on Oct. 18, 2026.