MCMAHON ROAD MUTUAL WATER COMPANY

HOLLISTER, CA · ~102 people served

Check your exact address → HOLLISTER overview

100

Excellent

PurityRadar safety score

PWSID

CA3500510

State

California

City

HOLLISTER

Population served

102

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

Violations on record

Unaddressed

Health-based

Enforcement actions

From EPA ECHO (SDWIS), most recent enforcement Jun 2008. Official EPA record →

Other · EPA contaminant 7000 began Jul 2006 Resolved

Monitoring & reporting · Total trihalomethanes (TTHM) began Jan 2006 Resolved

Monitoring & reporting · Haloacetic acids (HAA5) began Jan 2006 Resolved

Monitoring & reporting · Total coliform began Aug 2005 Resolved

Monitoring & reporting · Total trihalomethanes (TTHM) began Jan 2005 Resolved

Monitoring & reporting · Haloacetic acids (HAA5) began Jan 2005 Resolved

Monitoring & reporting · EPA contaminant 0999 began Jan 2005 Resolved

Monitoring & reporting · EPA contaminant 0999 began Oct 2004 Resolved

Monitoring & reporting · EPA contaminant 0999 began Jul 2004 Resolved

Monitoring & reporting · EPA contaminant 0999 began Apr 2004 Resolved

Monitoring & reporting · EPA contaminant 0999 began Jan 2004 Resolved

Max contaminant level (MCL) · Total coliform health-based began Nov 2000 Resolved

Recent enforcement actions

State action · SOX Jun 2008
State action · SFL Dec 2007
State action · SOX Sep 2007
State action · SOX Sep 2007
State action · SIA Apr 2007
State action · SOX Sep 2005
State action · SIA Sep 2005
State action · SOX Jul 2005

This profile is built from EPA public records for system CA3500510 — 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.