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Del Oro Water Co. - Magalia

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
363 people
Connections
110
Water source
Groundwater
Based in
Chico, CA
County
Butte
Owner
Private
The ZIP code it serves

95954

The short answer

1 result is above the health goal. The worst: Arsenic, above the health goal. No health-based violations on file since 2016.

What handles it

What was found

Copper: EPA’s file records a utility’s copper only when it exceeds the action level. The last here was 3.0 ppm, for the period ending Dec. 31, 2017. None since is on file, so it is not counted as a current finding.

Arsenic, total trihalomethanes (TTHM), haloacetic acids (HAA5) and nitrate: California’s own results, samples taken from April 28, 2020 to Aug. 19, 2025, with EPA’s 2012 to 2019 file for earlier years.

Chromium (total) and fluoride: EPA’s compliance monitoring file, samples taken from July 18, 2017 to July 18, 2017. Newer results are in the utility’s annual water quality report.

Above the health goal1

Arsenic

Comes from the source

Above the health goal

4.7ppb

Highest yearly average, 2021 to 2024

2024: not found

Averaged by year, the highest was 4.7 ppb, in 2021: below EPA’s legal limit of 10 ppb, but above its health goal of zero. Its highest single sample was 4.8 ppb. In 2024, the latest year on file, it wasn’t found in any of its two samples.

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 limits4

Total trihalomethanes (TTHM)

Forms or is added in treatment

Below EPA’s limits

46ppb

Highest yearly average, 2020 to 2025

2025, one sample: 33.5 ppb

Averaged by year, the highest was 46 ppb, in 2022, below EPA’s legal limit of 80 ppb. In 2025, the latest year on file, its one sample was 33.5 ppb. Earlier, from 2012 to 2019, EPA’s file shows a highest yearly average of 31 ppb, in 2016.

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

Below EPA’s limits

28ppb

Highest yearly average, 2020 to 2025

Averaged by year, the highest was 28 ppb, in 2025, below EPA’s legal limit of 60 ppb. That was also the latest year on file. Earlier, from 2012 to 2019, EPA’s file shows a highest yearly average of 20 ppb, in 2016.

What handles it

No certification claim covers this compound yet.

Nitrate

Comes from the source

Below EPA’s limits

3.8ppm

Highest sample; found in 12 of 12

2025 average: 3.1 ppm

The highest sample, in 2022, was 3.8 ppm, below EPA’s legal limit of 10 ppm. In 2025, the latest year on file, its two samples averaged 3.1 ppm. Earlier, from 2012 to 2019, EPA’s file shows a highest sample of 4.3 ppm, in 2012.

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

Below EPA’s limits

1.2ppb

Highest yearly average, 2017

Averaged by year, the highest was 1.2 ppb, in 2017, below EPA’s legal limit of 100 ppb. Its highest single sample was 1.4 ppb. That is the only year on file.

What handles it

2 compounds tested and not foundBelow the reporting level in every sample. Not found is not the same as zero.
  • Fluoride
  • 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

    Claim: Arsenic (Pentavalent)<=50 ppb Reduction

    For: 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

Compare five-year costs

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Violations since 2016

No health-based violations on file with EPA since 2016. There is 1 monitoring or reporting violation: a sample missed, late or not reported.

What this report can’t tell you

  • Everything else. Arsenic, total trihalomethanes (TTHM), haloacetic acids (HAA5) and nitrate results here are California’s own from 2020 on, with EPA’s national file for 2012 to 2019. Chromium (total) and fluoride come from EPA’s file alone, which ends in 2019. Del Oro Water Co. - Magalia’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 April 28, 2020 to Aug. 19, 2025; EPA’s compliance samples are from July 18, 2017 to July 18, 2017.

Testing your own tap

Del Oro Water Co. - Magalia’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 Del Oro Water Co. - Magalia serves, in a straight line. Call first: certification is test by test, and not every lab takes samples from homeowners.

  • Fruit Growers Laboratory, Inc.

    Chico, CA · about 17 miles

    Certified for bacteria

    (530) 343-5818

  • Cranmer Engineering, Inc.

    Grass Valley, CA · about 54 miles

    Certified for bacteria, nitrate, lead and copper, metals, minerals and other inorganics

    (530) 273-7284

  • Pace Analytical Services, LLC - Redding

    Redding, CA · about 64 miles

    Certified for bacteria

    (530) 999-4051

All 145 certified labs for California

Sources

PWSID CA0410009. Rebuilt from EPA data on Oct. 18, 2026.

Also in Butte County

All California utilities

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