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Water system · PWSID CA3400138

LOCKE WATER WORKS CO [SWS]

WALNUT GROVE, CA · ~80 people served

Check your exact address → WALNUT GROVE overview
100
Excellent
PurityRadar safety score

PWSID

CA3400138

State

California

City

WALNUT GROVE

Population served

80

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

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

15

Violations on record

1

Unaddressed

8

Health-based

28

Enforcement actions

From EPA ECHO (SDWIS), most recent enforcement Jan 2025. Official EPA record →

Monitoring & reporting · Lead & Copper Rule began Oct 2024 Unaddressed
Monitoring & reporting · Lead & Copper Rule began Oct 2017 Addressed
Other · EPA contaminant 7000 began Jul 2015 Resolved
Other · EPA contaminant 7000 began Jul 2013 Resolved
Other · EPA contaminant 7000 began Jul 2010 Resolved
Other · EPA contaminant 7000 began Jul 2009 Resolved
Max contaminant level (MCL) · Total coliform health-based began Mar 2001 Resolved
Max contaminant level (MCL) · Total coliform health-based began Feb 2001 Resolved
Max contaminant level (MCL) · Total coliform health-based began Nov 2000 Resolved
Max contaminant level (MCL) · Total coliform health-based began Jul 2000 Resolved
Max contaminant level (MCL) · Total coliform health-based began May 2000 Resolved
Max contaminant level (MCL) · Total coliform health-based began Apr 2000 Resolved

Recent enforcement actions

  • State action · SIA Jan 2025
  • State action · SFL Nov 2017
  • State action · SOX Nov 2015
  • State action · SFL Oct 2015
  • State action · SFL Jan 2014
  • State action · SOX Nov 2013
  • State action · SFL Nov 2010
  • State action · SOX Nov 2010

This profile is built from EPA public records for system CA3400138 — 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.