Sherwood Mobile Home Park
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
- 540 people
- Connections
- 185
- Water source
- Groundwater
- Based in
- Lancaster, CA
- County
- Los Angeles
- Owner
- Private
- Hardness
- Moderately hard
The ZIP code it serves
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
Chromium (total), nitrate, fluoride, total trihalomethanes (TTHM), arsenic and haloacetic acids (HAA5): California’s own results, samples taken from Sept. 2, 2020 to Oct. 7, 2025, with EPA’s 2012 to 2019 file for earlier years.
Uranium: EPA’s compliance monitoring file, samples taken from Aug. 20, 2018 to Oct. 2, 2019. Newer results are in the utility’s annual water quality report.
Below EPA’s limits4
Chromium (total)
Comes from the source
11.5ppb
Highest yearly average, 2021 to 2024
Averaged by year, the highest was 11.5 ppb, in 2024, below EPA’s legal limit of 100 ppb. Its highest single sample was 13 ppb. That was also the latest year on file. Earlier, from 2012 to 2019, EPA’s file shows a highest yearly average of 12.5 ppb, in 2018.
What handles it
- NSF/ANSI 58 look for “Chromium (Hexavalent) Reduction”
- NSF/ANSI 53 look for “Chromium Reduction”
Nitrate
Comes from the source
1.1ppm
Highest sample; found in 12 of 12
2025 average: 0.85 ppm
The highest sample, in 2022, was 1.1 ppm, below EPA’s legal limit of 10 ppm. In 2025, the latest year on file, its two samples averaged 0.85 ppm. Earlier, from 2012 to 2019, EPA’s file shows a highest sample of 1.5 ppm, in 2012.
What handles it
- NSF/ANSI 58 look for “Nitrate/Nitrite Reduction”
- NSF/ANSI 53 look for “Nitrate/Nitrite (30 ppm challenge)”
Fluoride
Forms or is added in treatment
0.27ppm
Highest yearly average, 2021 to 2024
Averaged by year, the highest was 0.27 ppm, in 2024, below EPA’s legal limit of 4.0 ppm. Its highest single sample was 0.33 ppm. That was also the latest year on file. Earlier, from 2012 to 2019, EPA’s file shows a highest yearly average of 0.27 ppm, in 2014.
What handles it
- NSF/ANSI 58 look for “Fluoride Reduction”
- NSF/ANSI 53 look for “Fluoride”
Total trihalomethanes (TTHM)
Forms or is added in treatment
1.1ppb
Highest yearly average, 2022 to 2025
Averaged by year, the highest was 1.1 ppb, in 2025, below EPA’s legal limit of 80 ppb. Its highest single sample was 3.4 ppb. That was also the latest year on file.
What handles it
- NSF/ANSI 53 look for “Trihalomethanes (TTHM) Reduction”
- NSF/ANSI 58 look for “Trihalomethanes (TTHM) Reduction”
4 compounds tested and not foundBelow the reporting level in every sample. Not found is not the same as zero.
- Arsenic
- Haloacetic acids (HAA5)
- Lead
- Uranium
Hardness
Moderately hard, typically 78 mg/L (4.5 grains per gallon), across 2 sampling points, 2021 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.
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. Chromium (total), nitrate, fluoride, total trihalomethanes (TTHM), arsenic and haloacetic acids (HAA5) results here are California’s own from 2020 on, with EPA’s national file for 2012 to 2019. Uranium comes from EPA’s file alone, which ends in 2019. Sherwood Mobile Home Park’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 Sept. 2, 2020 to Oct. 7, 2025; EPA’s compliance samples are from Aug. 20, 2018 to Oct. 2, 2019.
Testing your own tap
The 3 labs California certifies closest to the area Sherwood Mobile Home Park serves, in a straight line. Call first: certification is test by test, and not every lab takes samples from homeowners.
Geo-Monitor, Inc
Hesperia, CA · about 37 miles
Certified for bacteria
Pat-Chem Laboratories
San Fernando, CA · about 44 miles
Certified for bacteria, nitrate, lead and copper, metals, minerals and other inorganics, organic chemicals, disinfection byproducts, radioactivity
EMSL Analytical, Inc. (LA Testing)
South Pasadena, CA · about 45 miles
Certified for bacteria, asbestos
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 Aug. 4, 2021 to Aug. 7, 2024, read Oct. 10, 2026
- Limits and goals: each contaminant’s page, with its EPA source.
- How this page is built: methodology.
PWSID CA1900907. Rebuilt from EPA data on Oct. 18, 2026.
What to do next
- Nothing here is above a health goalIn EPA’s and California’s records for this utility. They don’t cover everything, which is why the next step matters.Every contaminant TapBuff tracks
- Get the utility’s own reportSherwood Mobile Home Park must send you a water quality report every year. It covers contaminants this page does not show, and has newer results than EPA’s national file for the ones here that come from it.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
- Decide if you want a filter at allA filter for taste or chlorine is a preference, not a need. The standards say what each kind can do.NSF/ANSI standards, decoded