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ZIP Code 91803 Water Quality
California · 278,049 people served · 9 water systems
A
ExcellentZIP code 91803 is in California and is a large city from a drinking-water-service perspective, with 278,049 people served by 9 EPA-registered public water systems. It corresponds to ALHAMBRA.
Within ZIP code 91803, the EPA Safe Drinking Water Information System (SDWIS) records no health-based Maximum Contaminant Level (MCL) exceedances during the past five years across the 9 water systems serving this postal area.
Last updated: 2026-05-18 · Source: EPA SDWIS
ZIP Code Location
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Cities in ZIP 91803
Water Systems Serving 91803
LOS ANGELES CWWD 37-ACTON
PWSID: CA1910248
4,805 served
LOS ANGELES CWWD 40, R 24,27,33-PEARBLSM
PWSID: CA1910203
11,509 served
LOS ANGELES CWWD 29 & 80-MALIBU
PWSID: CA1910204
32,348 served
LOS ANGELES CWWD 36-VAL VERDE
PWSID: CA1910185
6,376 served
LOS ANGELES CWWD 21-KAGEL CANYON
PWSID: CA1910075
708 served
LOS ANGELES CWWD 40 REG 4 & 34 LANCASTER
PWSID: CA1910070
208,129 served
LOS ANGELES CWWD 40, REG. 39-ROCK CREEK
PWSID: CA1910025
994 served
LOS ANGELES CWWD 40, REG. 35-N.E. L.A.
PWSID: CA1910027
612 served
LOS ANGELES CWWD 40, REG. 38-LAKE LA
PWSID: CA1910005
12,568 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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