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ZIP Code 95023 Water Quality
California · 52,826 people served · 19 water systems
C
FairZIP code 95023 is in California and is a mid-sized community from a drinking-water-service perspective, with 52,826 people served by 19 EPA-registered public water systems. It corresponds to HOLLISTER.
Within ZIP code 95023, the EPA Safe Drinking Water Information System (SDWIS) records 5 health-based violations during the past five years across 19 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 95023
Water Systems Serving 95023
SAN JUSTO MUTUAL WATER COMPANY
PWSID: CA3500550
160 served
SAN BENITO COUNTY WATER DISTRICT
PWSID: CA3510007
25 served
CREEKBRIDGE MUTUAL WATER COMPANY
PWSID: CA3500911
69 served
WHISPERING PINES INN
PWSID: CA3500810
38 served
VENTURE ESTATES MWC
PWSID: CA3500552
50 served
CASA DE FRUTA ORCHARDS
PWSID: CA3500511
53 served
CASA DE FRUTA WATER SYSTEM
PWSID: CA4300611
250 served
SPRINGWOOD ESTATES MWC
PWSID: CA3500575
50 served
VINEYARD ESTATES MWC
PWSID: CA3500579
90 served
SUNNYSLOPE COUNTY WATER DIST
PWSID: CA3510003
24,954 served
HOLLISTER RANCH ESTATES
PWSID: CA3500904
150 served
MCMAHON ROAD MUTUAL WATER COMPANY
PWSID: CA3500510
102 served
DUNNEVILLE ESTATES CSA #50
PWSID: CA3500910
120 served
CSA NO. 31 STONEGATE WS
PWSID: CA3500006
230 served
ROSA MORADA MUTUAL WATER COMPANY
PWSID: CA3500549
138 served
ASHFORD HIGHLANDS MWC
PWSID: CA3500900
132 served
HOLLISTER, CITY OF
PWSID: CA3510001
26,017 served
UNION HEIGHTS MWC
PWSID: CA3500825
98 served
COMSTOCK MUTUAL WATER COMPANY
PWSID: CA3500912
100 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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