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Stockdale Annex 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
433 people
Connections
141
Water source
Groundwater
Based in
Bakersfield, CA
County
Kern
Owner
Private
Hardness
Moderately hard
The ZIP code it serves

93309

The short answer

2 results are above the health goal. The worst: Nitrate, above the health goal. No health-based violations on file since 2016.

What handles it

What was found

Lead and copper: EPA SDWIS monitoring periods ending 1997 to 2023.

Nitrate, chromium (total), fluoride, arsenic, haloacetic acids (HAA5) and total trihalomethanes (TTHM): California’s own results, samples taken from July 15, 2020 to Aug. 19, 2025, with EPA’s 2012 to 2019 file for earlier years.

Above the health goal2

Nitrate

Comes from the source

Above the health goal

43ppm

Highest sample; found in 21 of 22

2025 average: 2.4 ppm

One sample, in 2021, was above EPA’s legal limit of 10 ppm, at 43 ppm. The next sample at the same point, within 30 days, kept the average above the limit. 10 ppm is also EPA’s health goal. In 2025, the latest year on file, its three samples averaged 2.4 ppm. EPA recorded no violation for nitrate at this utility since 2020. Earlier, from 2012 to 2019, EPA’s file shows a highest sample of 3.8 ppm, in 2014.

What handles it

  • NSF/ANSI 58 look for “Nitrate/Nitrite Reduction”
  • NSF/ANSI 53 look for “Nitrate/Nitrite (30 ppm challenge)”

Lead

Comes from pipes, often your own

Above the health goal

1.4ppb

90th percentile, 2021 to 2023

In the latest period, 9 in 10 homes sampled were at or below 1.4 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

Below EPA’s limits2

Chromium (total)

Comes from the source

Below EPA’s limits

11ppb

Highest yearly average, 2020 to 2024

2024: not found

Averaged by year, the highest was 11 ppb, in 2023, below EPA’s legal limit of 100 ppb. In 2024, the latest year on file, it wasn’t found in its one sample.

What handles it

Fluoride

Forms or is added in treatment

Below EPA’s limits

0.16ppm

Highest yearly average, 2020 to 2024

2024, one sample: 0.084 ppm

Averaged by year, the highest was 0.16 ppm, in 2020, below EPA’s legal limit of 4.0 ppm. In 2024, the latest year on file, its one sample was 0.084 ppm. Earlier, from 2012 to 2019, EPA’s file shows a highest yearly average of 0.2 ppm, in 2013.

What handles it

3 compounds tested and not foundBelow the reporting level in every sample. Not found is not the same as zero.
  • Arsenic
  • 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: Nitrate/Nitrite (30 ppm challenge), Lead Reduction

    For: Nitrate, Lead

  • NSF/ANSI 58

    Claims: Nitrate/Nitrite Reduction, Lead Reduction

    For: Nitrate, Lead

    Other certifiers’ wording: Nitrate

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

Compare five-year costs

The best reverse osmosis systems, ranked

The best water filters for lead, ranked

Hardness

Moderately hard, typically 85 mg/L (5 grains per gallon), across 3 sampling points, 2019 to 2024.

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.

Softeners compared at 5 grains per gallon, salt includedSoftener or salt-free conditioner?California water hardness, utility by utility

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. Nitrate, chromium (total), fluoride, arsenic, haloacetic acids (HAA5) and total trihalomethanes (TTHM) results here are California’s own from 2020 on, with EPA’s national file for 2012 to 2019. Stockdale Annex Mutual Water’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 July 15, 2020 to Aug. 19, 2025.

Testing your own tap

Stockdale Annex 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 Stockdale Annex Mutual Water serves, in a straight line. Call first: certification is test by test, and not every lab takes samples from homeowners.

  • Zalco Laboratories, Inc.

    Bakersfield, CA · about 4 miles

    Certified for bacteria, nitrate, metals, minerals and other inorganics, organic chemicals, disinfection byproducts

    (661) 395-0539

  • Pace Analytical Services, LLC dba BC Laboratories, Inc.

    Bakersfield, CA · about 4 miles

    Certified for bacteria, nitrate, lead and copper, metals, minerals and other inorganics, organic chemicals, disinfection byproducts, radioactivity

    (661) 327-4911

  • BSK Associates - Bakersfield Analytical Laboratory

    Bakersfield, CA · about 6 miles

    Certified for bacteria

    (661) 327-0671

All 145 certified labs for California

Sources

PWSID CA1500211. Rebuilt from EPA data on Oct. 18, 2026.

Towns it serves

Also in Kern County

All California utilities

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