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ZIP Code 93420 Water Quality
California · 19,765 people served · 11 water systems
F
FailingZIP code 93420 is in California and is a small city from a drinking-water-service perspective, with 19,765 people served by 11 EPA-registered public water systems. It overlaps with 2 communities including ARROYO GRANDE, HALCYON.
Within ZIP code 93420, the EPA Safe Drinking Water Information System (SDWIS) records 33 health-based violations during the past five years across 11 water systems serving this postal area. The grade of F 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 93420
Water Systems Serving 93420
CITY OF ARROYO GRANDE UTILITIES DIVISION
PWSID: CA4010001
17,963 served
TERRA DE ORO WATER COMPANY
PWSID: CA4000749
38 served
WOODLAND PARK MUTUAL WATER CO
PWSID: CA4000506
538 served
HALCYON WATER SYSTEM
PWSID: CA4000501
110 served
MESA DUNES MOBILE HOME ESTATES
PWSID: CA4000650
600 served
VARIAN RANCH MUTUAL WATER
PWSID: CA4000765
105 served
CANYON CREST MUTUAL BENEFIT WC
PWSID: CA4000230
133 served
H2O, INC
PWSID: CA4000741
70 served
LAGUNA NEGRA MUTUAL WATER CO.
PWSID: CA4000705
80 served
RANCHO NIPOMO WATER COMPANY
PWSID: CA4000771
44 served
KEN MAR GARDENS
PWSID: CA4000648
84 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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