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Public Water System
RANCHO SAN JOAQUIN WATER SYS
PWSID CA3900558 · California · 172 people served
A
ExcellentRANCHO SAN JOAQUIN WATER SYS is an EPA-regulated public water system in California (PWSID CA3900558). It serves an estimated 172 residents — a rural community of customers — across 1 community across 1 ZIP code.
RANCHO SAN JOAQUIN WATER SYS has maintained full EPA Safe Drinking Water Act compliance over the most recent five-year reporting window. No health-based Maximum Contaminant Level (MCL) exceedances are on record. The grade of A reflects this clean compliance history.
Service Area
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Centered on the averaged ZIP-code centroid of 1 ZIP served.
Population
172
Cities
1
ZIPs
1
Violations
0
EPA Health-Based Violations
Health-based Maximum Contaminant Level (MCL) violations on file for RANCHO SAN JOAQUIN WATER SYS over the past five years of EPA SDWIS reporting.
✅
No health-based violations in the last 5 years.
RANCHO SAN JOAQUIN WATER SYS's water systems have met EPA health-based Maximum Contaminant Level (MCL) requirements throughout the EPA reporting window. This does not mean zero detection of regulated contaminants — it means all measured concentrations remained below their federal action levels.
Cities Served by RANCHO SAN JOAQUIN WATER SYS
ZIP Codes Served
About this system
EPA records this system as PWSID CA3900558. Data reflects the most recent EPA SDWIS publication as of 2026-05-18. Public Water System Identifiers (PWSIDs) are assigned by the EPA's Safe Drinking Water Act program to track every regulated water utility in the United States. The first two letters typically indicate the state primacy agency. For real-time water quality information, contact RANCHO SAN JOAQUIN WATER SYS directly or review their annual Consumer Confidence Report (CCR).
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