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Arrowbear Park CWD

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
1,396 people
Connections
956
Water source
Groundwater
Based in
Arrowbear Lake, CA
County
San Bernardino
Owner
Local government
Hardness
Moderately hard
The ZIP code it serves

92382

The short answer

1 result is above the limit’s level with no violation recorded, and 1 more is above the health goal. The worst: Uranium, above the limit’s level, no violation. No health-based violations on file since 2016.

What handles it

What was found

Lead and copper: EPA SDWIS monitoring periods ending 2008 to 2026.

Uranium, fluoride, total trihalomethanes (TTHM), arsenic, chromium (total), haloacetic acids (HAA5) and nitrate: California’s own results, samples taken from Jan. 7, 2020 to July 1, 2026, with EPA’s 2012 to 2019 file for earlier years.

Above the limit’s level, no violation recorded1

Uranium

Comes from the source

Above the limit’s level, no violation

84.9ppb

Highest yearly average, 2020 to 2026

2026 average: 79.7 ppb

Averaged by year, the highest was 84.9 ppb, in 2025, about 2.8 times EPA’s legal limit of 30 ppb. Its highest single sample was 224 ppb. In 2026, the latest year on file, its 22 samples averaged 79.7 ppb, above the limit. EPA judges this limit on running averages at each sampling point, and recorded no violation for uranium at this utility since 2020. Results like these with no violation often include water sampled before treatment or blending; the utility’s annual report says what reaches the tap. Earlier, from 2012 to 2019, EPA’s file shows a highest yearly average of 102 ppb, in 2012.

What handles it

Above the health goal1

Lead

Comes from pipes, often your own

Above the health goal

5.4ppb

90th percentile, 2024 to 2026

In the latest period, 9 in 10 homes sampled were at or below 5.4 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

Fluoride

Forms or is added in treatment

Below EPA’s limits

0.12ppm

Highest yearly average, 2020 to 2026

Averaged by year, the highest was 0.12 ppm, in 2026, below EPA’s legal limit of 4.0 ppm. Its highest single sample was 0.2 ppm. That was also the latest year on file. Earlier, from 2012 to 2019, EPA’s file shows a highest yearly average of 0.14 ppm, in 2012.

What handles it

Total trihalomethanes (TTHM)

Forms or is added in treatment

Below EPA’s limits

2.3ppb

Highest yearly average, 2020 to 2026

2026: not found

Averaged by year, the highest was 2.3 ppb, in 2022, below EPA’s legal limit of 80 ppb. Its highest single sample was 4.6 ppb. In 2026, the latest year on file, it wasn’t found in its one sample.

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
  • Chromium (total)
  • Haloacetic acids (HAA5)
  • Nitrate

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.”

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 water filters for lead, ranked

Hardness

Moderately hard, typically 100 mg/L (5.8 grains per gallon), across 5 sampling points, 2020 to 2026.

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 5.8 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.

What this report can’t tell you

  • Everything else. Uranium, fluoride, total trihalomethanes (TTHM), arsenic, chromium (total), haloacetic acids (HAA5) and nitrate results here are California’s own from 2020 on, with EPA’s national file for 2012 to 2019. Arrowbear Park CWD’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. 7, 2020 to July 1, 2026.

Testing your own tap

Arrowbear Park CWD’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 Arrowbear Park CWD serves, in a straight line. Call first: certification is test by test, and not every lab takes samples from homeowners.

  • BSK Associates - San Bernardino Analytical Laboratory

    San Bernardino, CA · about 14 miles

    Certified for bacteria

    (559) 497-2888

  • Clinical Laboratory of San Bernardino, Inc.

    Grand Terrace, CA · about 17 miles

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

    (909) 825-7693

  • Geo-Monitor, Inc

    Hesperia, CA · about 20 miles

    Certified for bacteria

    (760) 244-3481

All 145 certified labs for California

Sources

PWSID CA3610110. Rebuilt from EPA data on Oct. 18, 2026.

Towns it serves

Also in San Bernardino County

All California utilities

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