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South Mesa WC water quality report, rewritten

Serves
10,108
Connections
3,108
Water source
Groundwater
Based in
Calimesa, CA
County
Riverside
Owner
Private
The 2 ZIP codes it serves

92320, 92399

PWSID CA3310017 · EPA data

Read this first

Nothing in the federal data for this utility is above a health goal. That covers PFAS, lithium, lead and copper; it does not cover everything, so read what this report cannot tell you below.

No health-based violations on file since 2016.

What was found

Highlighted: above the health goal, or EPA’s health benchmark where there is no goal. Circled: above the legal limit in at least one sample, or the action level. Every scale puts that line at its middle.

PFAS and lithium: EPA UCMR 5, samples taken from Jan. 9, 2023 to Sept. 20, 2023. Each blue tick on a scale is one sample where it was found.

NSF’s PFAS claims are tested to below 20 ppt. EPA’s limit is 10 ppt, and EPA says no certification yet shows a filter reaching its levels.

PFHxS

Comes from the source

3.5ppt

Highest of 16 samples; found in one

Detected, below the legal limit and the health goal.

What handles it

PFBS

Comes from the source

4.7ppt

Highest of 16 samples; found in one

Below EPA’s hazard index benchmark of 2,000 ppt. PFBS has no legal limit or health goal of its own.

What handles it

Also found, with no federal limit

EPA measured these PFAS to learn how often they occur. None has a legal limit or a health goal yet.

CompoundHighest sampleFound inCertification claim
PFPeA8.9 ppt2 of 16None covers it
PFHxA6.8 ppt2 of 16None covers it

Tested and not found

Below EPA’s minimum reporting level in every sample taken from Jan. 9, 2023 to Sept. 20, 2023. Not found means not measured above that level, which is not the same as zero.

All 27 compounds tested and not found
  • 11Cl-PF3OUdS
  • 4:2 FTS
  • 6:2 FTS
  • 8:2 FTS
  • 9Cl-PF3ONS
  • ADONA
  • HFPO-DA (GenX)
  • Lead
  • Lithium
  • NEtFOSAA
  • NFDHA
  • NMeFOSAA
  • PFBA
  • PFDA
  • PFDoA
  • PFEESA
  • PFHpA
  • PFHpS
  • PFMBA
  • PFMPA
  • PFNA
  • PFOA
  • PFOS
  • PFPeS
  • PFTA
  • PFTrDA
  • PFUnA

Violations since 2016

No health-based violations on file with EPA since 2016.

What this report cannot tell you

  • Levels of everything else. Federal bulk data carries results for PFAS, lithium, lead and copper, and violations for the rest. Nitrate, arsenic, disinfection byproducts and other levels are in South Mesa WC’s own annual report, which it must send you every year.
  • 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.
  • Anything after the latest data. SDWIS data is from 2026 Q2; UCMR 5 samples are from Jan. 9, 2023 to Sept. 20, 2023.

Other California utilities

All California utilities

Sources

What to do next

  • Nothing here is above a health goal

    In the federal data for this utility. That data does not cover everything, which is why the next step matters.

    Every contaminant TapBuff tracks

  • Get the utility’s own report

    South Mesa WC must send you a water quality report every year. It lists nitrate, arsenic and byproduct levels this page cannot.

    How to read it

  • Test your own tap for lead

    Your 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 all

    A filter for taste or chlorine is a preference, not a need. The standards say what each kind can do.

    NSF/ANSI standards, decoded