Sierra Breeze Mutual Water Company
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
- 199 people
- Connections
- 71
- Water source
- Groundwater
- Based in
- Inyokern, CA
- County
- Kern
- Owner
- Private
- Hardness
- Varies by source
The ZIP code it serves
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 itWhat was found
Nitrate, uranium, fluoride, arsenic and chromium (total): California’s own results, samples taken from Jan. 6, 2020 to April 8, 2026, with EPA’s 2012 to 2019 file for earlier years.
Above the health goal2
Nitrate
Comes from the source
17ppm
Highest sample; found in 48 of 48
2026 average: 4.7 ppm
One sample, in 2024, was above EPA’s legal limit of 10 ppm, at 17 ppm. The next sample at the same point, within 30 days, brought the average back under the limit. 10 ppm is also EPA’s health goal. In 2026, the latest year on file, its two samples averaged 4.7 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 9.5 ppm, in 2015.
What handles it
- NSF/ANSI 58 look for “Nitrate/Nitrite Reduction”
- NSF/ANSI 53 look for “Nitrate/Nitrite (30 ppm challenge)”
Uranium
Comes from the source
9.1ppb
Highest yearly average, 2020
Averaged by year, the highest was 9.1 ppb, in 2020: 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 limits1
Fluoride
Forms or is added in treatment
0.8ppm
Highest yearly average, 2020 to 2025
2025, one sample: 0.67 ppm
Averaged by year, the highest was 0.8 ppm, in 2022, below EPA’s legal limit of 4.0 ppm. In 2025, the latest year on file, its one sample was 0.67 ppm. Earlier, from 2012 to 2019, EPA’s file shows a highest yearly average of 0.81 ppm, in 2013.
What handles it
- NSF/ANSI 58 look for “Fluoride Reduction”
- NSF/ANSI 53 look for “Fluoride”
3 compounds tested and not foundBelow the reporting level in every sample. Not found is not the same as zero.
- Arsenic
- Chromium (total)
- 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: Nitrate/Nitrite (30 ppm challenge)
For: Nitrate
- NSF/ANSI 58
Claims: Nitrate/Nitrite Reduction, Uranium
For: Nitrate, Uranium
Other certifiers’ wording: Nitrate
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
Countertop reverse osmosis
- IAPMO listing:NSF/ANSI 42NSF/ANSI 53NSF/ANSI 58NSF/ANSI 401checked Oct. 4, 2026
Certified for: Nitrate
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: Nitrate
Culligan 10-Cup Pitcher with ZeroWater Technology (ZEROP10)
Pitcher
- IAPMO listing:NSF/ANSI 42NSF/ANSI 53NSF/ANSI 401checked Oct. 9, 2026
Certified for: Nitrate
Hardness
Hard to very hard depending on the source, 140 to 265 mg/L (8.2 to 15.5 grains per gallon), across 2 sampling points, 2019 to 2025.
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. Nitrate, uranium, fluoride, arsenic and chromium (total) results here are California’s own from 2020 on, with EPA’s national file for 2012 to 2019. Sierra Breeze Mutual Water Company’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. 6, 2020 to April 8, 2026.
Testing your own tap
No lab California certifies is within 75 miles of the area Sierra Breeze Mutual Water Company serves on the state’s list. Some take samples by mail; the state’s page lists them all.
All 145 certified labs for CaliforniaSources
- 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
- Hardness: California State Water Resources Control Board, Division of Drinking Water, results from July 22, 2019 to July 14, 2025, read Oct. 10, 2026
- Limits and goals: each contaminant’s page, with its EPA source.
- How this page is built: methodology.
PWSID CA1500447. 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 Nitrate
- Get the utility’s own reportSierra Breeze Mutual Water Company 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