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ZIP Code 93257 Water Quality
California · 64,091 people served · 7 water systems
D
PoorZIP code 93257 is in California and is a mid-sized community from a drinking-water-service perspective, with 64,091 people served by 7 EPA-registered public water systems. It corresponds to PORTERVILLE.
Within ZIP code 93257, the EPA Safe Drinking Water Information System (SDWIS) records 9 health-based violations during the past five years across 7 water systems serving this postal area. The grade of D 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 93257
Water Systems Serving 93257
EAGLE'S NEST RESORT
PWSID: CA5400602
60 served
SIERRA MUTUAL WATER COMPANY
PWSID: CA5403110
43 served
FOOTHILL APARTMENTS
PWSID: CA5400769
41 served
LAKE SUCCESS MOBILE LODGE
PWSID: CA5400660
75 served
PORTERVILLE, CITY OF
PWSID: CA5410010
63,487 served
PORTERVILLE-JONES CORNER
PWSID: CA5410048
339 served
PORTERVILLE - EAST PLANO
PWSID: CA5400767
46 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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