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Oakvale 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
260 people
Connections
88
Water source
Groundwater
Based in
Escondidoâ, CA
County
San Diego
Owner
Private
Hardness
Very hard
The ZIP code it serves

92027

The short answer

1 result is above EPA’s legal limit, and 2 more are above the health goal. The worst: Uranium, above the legal limit. 4 health-based violations since 2016.

What handles it

What was found

Uranium, nitrate, arsenic, total trihalomethanes (TTHM), haloacetic acids (HAA5), fluoride and chromium (total): California’s own results, samples taken from Jan. 9, 2020 to June 2, 2026, with EPA’s 2012 to 2019 file for earlier years.

Above the legal limit1

Uranium

Comes from the source

Above the legal limit

200ppb

Highest yearly average, 2020 to 2026

2026 average: 153 ppb

Averaged by year, the highest was 200 ppb, in 2023, about 6.7 times EPA’s legal limit of 30 ppb. Its highest single sample was 2,384 ppb. In 2026, the latest year on file, its 12 samples averaged 153 ppb, above the limit. EPA recorded a violation for uranium at this utility in 2024. Earlier, from 2012 to 2019, EPA’s file shows a highest yearly average of 73.9 ppb, in 2017, and EPA recorded a violation in 2016.

What handles it

Above the health goal2

Nitrate

Comes from the source

Above the health goal

11ppm

Highest sample; found in 31 of 39

2026 average: 3.2 ppm

One sample, in 2024, was above EPA’s legal limit of 10 ppm, at 11 ppm. No follow-up sample at that point within 30 days is on file. 10 ppm is also EPA’s health goal. In 2026, the latest year on file, its five samples averaged 3.2 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 1.5 ppm, in 2019.

What handles it

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

Arsenic

Comes from the source

Above the health goal

0.9ppb

Highest yearly average, 2020 to 2023

2023: not found

Averaged by year, the highest was 0.9 ppb, in 2020: below EPA’s legal limit of 10 ppb, but above its health goal of zero. In 2023, the latest year on file, it wasn’t found in its one sample.

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

54.4ppb

Highest yearly average, 2020 to 2025

2025, one sample: 32.4 ppb

Averaged by year, the highest was 54.4 ppb, in 2024, below EPA’s legal limit of 80 ppb. In 2025, the latest year on file, its one sample was 32.4 ppb. Earlier, from 2012 to 2019, EPA’s file shows a highest yearly average of 27 ppb, in 2018.

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

6.8ppb

Highest yearly average, 2020 to 2025

2025, one sample: 5.5 ppb

Averaged by year, the highest was 6.8 ppb, in 2020, below EPA’s legal limit of 60 ppb. In 2025, the latest year on file, its one sample was 5.5 ppb.

What handles it

No certification claim covers this compound yet.

Fluoride

Forms or is added in treatment

Below EPA’s limits

0.28ppm

Highest yearly average, 2020 to 2023

2023, one sample: 0.21 ppm

Averaged by year, the highest was 0.28 ppm, in 2022, below EPA’s legal limit of 4.0 ppm. Its highest single sample was 0.38 ppm. In 2023, the latest year on file, its one sample was 0.21 ppm. Earlier, from 2012 to 2019, EPA’s file shows a highest yearly average of 0.8 ppm, in 2013.

What handles it

Chromium (total)

Comes from the source

Below EPA’s limits

0.2ppb

Highest yearly average, 2020 to 2023

2023: not found

Averaged by year, the highest was 0.2 ppb, in 2020, below EPA’s legal limit of 100 ppb. In 2023, the latest year on file, it wasn’t found in its one sample.

What handles it

One compound tested and not foundBelow the reporting level in every sample. Not found is not the same as zero.
  • 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

    Claims: Nitrate/Nitrite (30 ppm challenge), Arsenic (Pentavalent)<=50 ppb Reduction

    For: Nitrate, Arsenic

    Other certifiers’ wording: Arsenic (III) (50 ppb influent level)

  • NSF/ANSI 58

    Claims: Uranium, Nitrate/Nitrite Reduction, Arsenic (Pentavalent)<=50 ppb Reduction

    For: Uranium, Nitrate, Arsenic

    Other certifiers’ wording: Nitrate; 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

The best reverse osmosis systems, ranked

Hardness

Very hard, typically 353 mg/L (20.6 grains per gallon), across 3 sampling points, 2019 to 2023.

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 20.6 grains per gallon, salt includedSoftener or salt-free conditioner?California water hardness, utility by utility

Violations since 2016

Contaminant or ruleTypePeriodMeasuredStatus
Combined UraniumThe running average was above the legal limit.EPA: Maximum Contaminant Level Violation, AverageJan. 1, 2024 to March 31, 202438.4 PCI/LResolved
Combined UraniumThe running average was above the legal limit.EPA: Maximum Contaminant Level Violation, AverageJuly 1, 2016 to Sept. 30, 201651.7 PCI/LResolved
Combined UraniumThe running average was above the legal limit.EPA: Maximum Contaminant Level Violation, AverageApril 1, 2016 to June 30, 201689.4 PCI/LResolved
Combined UraniumThe running average was above the legal limit.EPA: Maximum Contaminant Level Violation, AverageJan. 1, 2016 to March 31, 2016113 PCI/LResolved
Health-based violations only. Resolved and archived mean the utility returned to compliance or the state closed the record. 4 monitoring or reporting violations not shown.

What this report can’t tell you

  • Everything else. Uranium, nitrate, arsenic, total trihalomethanes (TTHM), haloacetic acids (HAA5), fluoride and chromium (total) results here are California’s own from 2020 on, with EPA’s national file for 2012 to 2019. Oakvale Park’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. 9, 2020 to June 2, 2026.

Testing your own tap

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

  • Applied Industrial Microbiology, Inc.

    Vista, CA · about 15 miles

    Certified for bacteria, nitrate

    (760) 295-0430

  • Alpha Analytical Laboratories, Inc. - San Diego

    Vista, CA · about 16 miles

    Certified for bacteria, nitrate, minerals and other inorganics

    (760) 536-3352

  • EMSL Analytical, Inc.

    San Diego, CA · about 23 miles

    Certified for bacteria

    (800) 220-3675

All 145 certified labs for California

Sources

PWSID CA3700962. Rebuilt from EPA data on Oct. 18, 2026.

Also in San Diego County

All California utilities

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