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ZIP Code 21704 Water Quality
Maryland · 85,001 people served · 14 water systems
A
ExcellentZIP code 21704 is in Maryland and is a mid-sized community from a drinking-water-service perspective, with 85,001 people served by 14 EPA-registered public water systems. It corresponds to FREDERICK.
Within ZIP code 21704, the EPA Safe Drinking Water Information System (SDWIS) records no health-based Maximum Contaminant Level (MCL) exceedances during the past five years across the 14 water systems serving this postal area.
Last updated: 2026-05-18 · Source: EPA SDWIS
ZIP Code Location
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Cities in ZIP 21704
Water Systems Serving 21704
NEW DESIGN - FREDERICK COUNTY
PWSID: MD0100030
74,911 served
FOUNTAINDALE SOUTH
PWSID: MD0100013
2,610 served
WHITE ROCK
PWSID: MD0100026
256 served
WATERSIDE
PWSID: MD0100029
1,509 served
CLOVERHILL 3 - CONSECUTIVE TO MD0100015
PWSID: MD0100031
888 served
BRADFORD ESTATES
PWSID: MD0100032
178 served
ROSEMONT DISTRIBUTION SYSTEM
PWSID: MD0100045
237 served
LIBERTYTOWN APARTMENTS
PWSID: MD0100036
97 served
COPPERFIELD
PWSID: MD0100037
338 served
LIBERTYTOWN EAST
PWSID: MD0100038
140 served
SAM HILL ESTATES
PWSID: MD0100040
1,036 served
KNOLLS OF WINDSOR
PWSID: MD0100041
1,553 served
CAMBRIDGE FARMS
PWSID: MD0100033
953 served
COUNTRY MEADOWS OF FREDERICK
PWSID: MD0100047
295 served
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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