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MD 73 Quartz Mountain

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
375 people
Connections
127
Water source
Groundwater
Based in
Madera, CA
County
Madera
Owner
Local government
Hardness
Hard
The ZIP code it serves

93614

The short answer

2 results are above the health goal. The worst: Lead, 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 2017 to 2026.

Arsenic, fluoride, chromium (total), nitrate, total trihalomethanes (TTHM) and uranium: California’s own results, samples taken from March 17, 2020 to March 9, 2026, with EPA’s 2012 to 2019 file for earlier years.

Above the health goal2

Lead

Comes from pipes, often your own

Above the health goal

4.9ppb

90th percentile, 2024 to 2026

In the latest period, 9 in 10 homes sampled were at or below 4.9 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

Arsenic

Comes from the source

Above the health goal

1.6ppb

Highest yearly average, 2020 to 2026

2026: not found

Averaged by year, the highest was 1.6 ppb, in 2020: below EPA’s legal limit of 10 ppb, but above its health goal of zero. Its highest single sample was 1.8 ppb. In 2026, the latest year on file, it wasn’t found in any of its two samples. Earlier, from 2012 to 2019, EPA’s file shows a highest yearly average of 1.4 ppb, in 2014.

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 limits1

Fluoride

Forms or is added in treatment

Below EPA’s limits

0.19ppm

Highest yearly average, 2020 to 2026

2026 average: 0.15 ppm

Averaged by year, the highest was 0.19 ppm, in 2023, below EPA’s legal limit of 4.0 ppm. Its highest single sample was 0.2 ppm. In 2026, the latest year on file, its two samples averaged 0.15 ppm. Earlier, from 2012 to 2019, EPA’s file shows a highest yearly average of 0.18 ppm, in 2018.

What handles it

4 compounds tested and not foundBelow the reporting level in every sample. Not found is not the same as zero.
  • Chromium (total)
  • Nitrate
  • Total trihalomethanes (TTHM)
  • Uranium

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: Lead Reduction, Arsenic (Pentavalent)<=50 ppb Reduction

    For: Lead, Arsenic

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

  • NSF/ANSI 58

    Claims: Lead Reduction, Arsenic (Pentavalent)<=50 ppb Reduction

    For: Lead, Arsenic

    Other certifiers’ wording: Arsenic (Pentavalent)<=300 ppb Reduction; Arsenic (V) (300 ppb influent level)

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

The best reverse osmosis systems, ranked

Hardness

Hard, typically 161 mg/L (9.4 grains per gallon), across 2 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 9.4 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 are 2 monitoring or reporting violations: a sample missed, late or not reported.

What this report can’t tell you

  • Everything else. Arsenic, fluoride, chromium (total), nitrate, total trihalomethanes (TTHM) and uranium results here are California’s own from 2020 on, with EPA’s national file for 2012 to 2019. MD 73 Quartz Mountain’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 March 17, 2020 to March 9, 2026.

Testing your own tap

MD 73 Quartz Mountain’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 MD 73 Quartz Mountain serves, in a straight line. Call first: certification is test by test, and not every lab takes samples from homeowners.

  • SGS North America, Inc.

    Clovis, CA · about 25 miles

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

    (559) 862-2118

  • Dellavalle Laboratory, Inc.

    Fresno, CA · about 31 miles

    Certified for bacteria, nitrate, lead and copper, metals, minerals and other inorganics, radioactivity

    (559) 233-6129

  • BSK Associates

    Fresno, CA · about 32 miles

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

    (559) 497-2888

All 145 certified labs for California

Sources

PWSID CA2000690. Rebuilt from EPA data on Oct. 18, 2026.

Towns it serves

Also in Madera County

All California utilities

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