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Public Water System
MERCER ISLAND CITY OF
PWSID WA5353640 · Washington · 31,057 people served
A
ExcellentMERCER ISLAND CITY OF is an EPA-regulated public water system in Washington (PWSID WA5353640). It serves an estimated 31,057 residents — a small city of customers — across 1 community across 1 ZIP code.
MERCER ISLAND CITY OF 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
31,057
Cities
1
ZIPs
1
Violations
0
EPA Health-Based Violations
Health-based Maximum Contaminant Level (MCL) violations on file for MERCER ISLAND CITY OF over the past five years of EPA SDWIS reporting.
✅
No health-based violations in the last 5 years.
MERCER ISLAND CITY OF'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 MERCER ISLAND CITY OF
ZIP Codes Served
About this system
EPA records this system as PWSID WA5353640. 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 MERCER ISLAND CITY OF directly or review their annual Consumer Confidence Report (CCR).
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