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ZIP Code 21661 Water Quality
Maryland · 1,750 people served · 1 water systems
A
ExcellentZIP code 21661 is in Maryland and is a rural community from a drinking-water-service perspective, with 1,750 people served by 1 EPA-registered public water systems. It corresponds to ROCK HALL.
Within ZIP code 21661, the EPA Safe Drinking Water Information System (SDWIS) records no health-based Maximum Contaminant Level (MCL) exceedances during the past five years across the 1 water system serving this postal area.
Last updated: 2026-05-18 · Source: EPA SDWIS
ZIP Code Location
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Cities in ZIP 21661
Water Systems Serving 21661
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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