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Water system · PWSID CA3310017

SOUTH MESA WC

CALIMESA, CA · ~10,108 people served

Check your exact address → CALIMESA overview
100
Excellent
PurityRadar safety score

PWSID

CA3310017

State

California

City

CALIMESA

Population served

10,108

Primary source

Groundwater

Score history

No change since tracking began Jun 18, 2026.

Jun 18, 2026 · score 100 Jun 18, 2026 · score 100

2 score updates logged since tracking began Jun 18, 2026. Each future EPA re-score adds a point.

PFAS & contaminant readings

Latest detections from EPA’s UCMR5 monitoring (through Sep 2023). Levels in parts per trillion (ppt).

PFHxS

Perfluorohexanesulfonic acid

3.5 ppt

limit 10 ppt

Below EPA limit

PFPeA

8.9 ppt

limit —

No federal limit

PFHxA

6.8 ppt

limit —

No federal limit

PFBS

4.7 ppt

limit —

No federal limit

Violations & enforcement

7

Violations on record

0

Unaddressed

2

Health-based

9

Enforcement actions

From EPA ECHO (SDWIS), most recent enforcement Oct 2014. Official EPA record →

Max contaminant level (MCL) · Fluoride health-based began Jul 2014 Resolved
Max contaminant level (MCL) · Fluoride health-based began Apr 2014 Resolved
Monitoring & reporting · Lead & Copper Rule began Oct 2013 Resolved
Monitoring & reporting · Fluoride began Apr 2010 Resolved
Monitoring & reporting · Total trihalomethanes (TTHM) began Jan 2009 Resolved
Monitoring & reporting · Haloacetic acids (HAA5) began Jan 2009 Resolved
Monitoring & reporting · Lead & Copper Rule began Jun 1993 Resolved

Recent enforcement actions

  • State action · SOX Oct 2014
  • State action · SFL Oct 2014
  • State action · SFJ Oct 2013
  • State action · SOX Oct 2013
  • State action · SOX Jan 2011
  • State action · SIA Jan 2011
  • State action · SIA Feb 2010
  • State action · SOX Jan 2010

Area water-quality monitoring

Environmental monitoring (rivers, wells, intakes) recorded in this system’s service area in the EPA/USGS Water Quality Portal since 2018 — source/ambient water, not finished tap water. Context for the watershed, not a reading from your tap.

ContaminantMedian · max · samples

Nitrate

1 station · latest Aug 2021

6.3 · max 6.3 mg/l as N · 2

Arsenic

1 station · latest Aug 2021

0.12 · max 0.12 ug/l · 1

Fluoride

1 station · latest Aug 2021

0.96 · max 0.96 mg/l · 1

Uranium

1 station · latest Aug 2021

0.659 · max 0.659 ug/l · 1

Source: Water Quality Portal (EPA/USGS/state agencies). Values are as-reported and aren’t health thresholds.

This profile is built from EPA public records for system CA3310017 — SDWIS violations and UCMR5 PFAS sampling. The score is system-level and can’t account for your home’s plumbing (older pipes can add lead at the tap). For health decisions, check your exact address, read the utility’s Consumer Confidence Report, and confirm with your provider.