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ZIP Code 04421 Water Quality
Maine · 1,056 people served · 2 water systems
C
FairZIP code 04421 is in Maine and is a rural community from a drinking-water-service perspective, with 1,056 people served by 2 EPA-registered public water systems. It corresponds to CASTINE.
Within ZIP code 04421, the EPA Safe Drinking Water Information System (SDWIS) records 5 health-based violations during the past five years across 2 water systems serving this postal area. The grade of C reflects the aggregate compliance pattern, not the current daily water quality.
Last updated: 2026-05-18 · Source: EPA SDWIS
ZIP Code Location
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Cities in ZIP 04421
Water Systems Serving 04421
About ZIP-code water data
Postal-code level water quality data is built up from the underlying water systems — multiple ZIPs may share a single utility, and a single ZIP can span multiple utilities. For property-level information, contact the specific utility serving your address. EPA data on this page was last refreshed on 2026-05-18.
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