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Water system · PWSID CA2810003

NAPA, CITY OF

NAPA, CA · ~84,804 people served

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

PWSID

CA2810003

State

California

City

NAPA

Population served

84,804

Primary source

Surface water

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

No PFAS detections are on record for this system from EPA’s UCMR5 monitoring (2023–25). Absence of a detection isn’t a guarantee — not every system was sampled, and this dataset doesn’t cover other contaminants.

Violations & enforcement

7

Violations on record

0

Unaddressed

7

Health-based

13

Enforcement actions

From EPA ECHO (SDWIS), most recent enforcement Apr 2015. Official EPA record →

Max contaminant level (MCL) · Total trihalomethanes (TTHM) health-based began Jan 2016 Resolved
Max contaminant level (MCL) · Total trihalomethanes (TTHM) health-based began Oct 2015 Resolved
Max contaminant level (MCL) · Total trihalomethanes (TTHM) health-based began Jul 2015 Resolved
Max contaminant level (MCL) · Total trihalomethanes (TTHM) health-based began Apr 2015 Resolved
Max contaminant level (MCL) · Total trihalomethanes (TTHM) health-based began Jan 2015 Resolved
Max contaminant level (MCL) · Haloacetic acids (HAA5) health-based began Jul 2013 Resolved
Treatment technique · EPA contaminant 0200 health-based began Apr 1995 Resolved

Recent enforcement actions

  • State action · SOX Apr 2015
  • State action · SFL Feb 2015
  • State action · SOX Feb 2014
  • State action · SFL Aug 2013
  • EPA/federal action · EOX Mar 2000
  • State action · SFJ Oct 1999
  • State action · SFJ May 1995
  • State action · SOX May 1995

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 Jun 2022

0.227 · max 0.227 mg/l as N · 2

Arsenic

1 station · latest Jun 2022

4.5 · max 4.5 ug/l · 1

Copper

1 station · latest Jun 2022

0.53 · max 0.53 ug/l · 1

Fluoride

1 station · latest Jun 2022

0.14 · max 0.14 mg/l · 1

Lead

1 station · latest Jun 2022

0.291 · max 0.291 ug/l · 1

Manganese

1 station · latest Jun 2022

18.5 · max 18.5 ug/l · 1

Uranium

1 station · latest Jun 2022

2.6 · max 2.6 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 CA2810003 — 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.