SONOMA MOUNTAIN COUNTY WATER DISTRICT

SANTA ROSA, CA · ~181 people served

Check your exact address → SANTA ROSA overview

100

Excellent

PurityRadar safety score

PWSID

CA4900580

State

California

City

SANTA ROSA

Population served

181

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 Oct 2015. Official EPA record →

Monitoring & reporting · Total coliform began Sep 2015 Resolved

Max contaminant level (MCL) · Total coliform health-based began Jan 2011 Resolved

Monitoring & reporting · Total coliform began Mar 2009 Resolved

Monitoring & reporting · Nitrate began Jan 2006 Resolved

Monitoring & reporting · Total coliform began Jul 1996 Resolved

Monitoring & reporting · Total coliform began Oct 1994 Resolved

Monitoring & reporting · Lead & Copper Rule began Jul 1993 Resolved

Recent enforcement actions

State action · SOX Oct 2015
State action · SFL Oct 2015
State action · SFL Mar 2011
State action · SOX Feb 2011
State action · SFL May 2009
State action · SOX Apr 2009
State action · SFL Jun 2007
State action · SOX Jun 2007

This profile is built from EPA public records for system CA4900580 — 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.