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ZIP Code 59101 Water Quality
Montana · 124,881 people served · 20 water systems
F
FailingZIP code 59101 is in Montana and is a mid-sized community from a drinking-water-service perspective, with 124,881 people served by 20 EPA-registered public water systems. It corresponds to BILLINGS.
Within ZIP code 59101, the EPA Safe Drinking Water Information System (SDWIS) records 27 health-based violations during the past five years across 20 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 59101
Water Systems Serving 59101
PIONEER WATER SERVICE
PWSID: MT0004226
900 served
FISHER WATER SERVICE
PWSID: MT0001848
750 served
PEKS MOBILE HOME COURT
PWSID: MT0004714
95 served
WESTANA MOBILE MANOR HAMILTON
PWSID: MT0000634
90 served
MOUNTAIN MEADOWS ESTATES LLP
PWSID: MT0001791
300 served
STONE CREEK SUBDIVISION
PWSID: MT0005183
378 served
SARTORIE LEGACY HOMES
PWSID: MT0005129
35 served
SKYCREST ESTATES SUBDIVISION
PWSID: MT0004964
235 served
BLACK ROCK ESTATES SUBDIVISION
PWSID: MT0004881
75 served
SHILOH ROAD DEVELOPMENT
PWSID: MT0005178
315 served
CRYSTAL SPRINGS WATER SYSTEM
PWSID: MT0003986
225 served
GRANITE PARK WATER ASSOCIATION
PWSID: MT0004563
250 served
SUNDANCE SUBDIVISION
PWSID: MT0005056
378 served
WELLS GARDEN ESTATES
PWSID: MT0002927
240 served
OAK RIDGE ESTATES
PWSID: MT0004250
200 served
DOUBLE DIAMOND SUBDIVISION ARBOR HILLS
PWSID: MT0004845
50 served
C & C COMMUNITY INC
PWSID: MT0005017
145 served
LOCKWOOD WATER AND SEWER DISTRICT
PWSID: MT0000156
5,900 served
BILLINGS CITY OF
PWSID: MT0000153
114,000 served
EMERALD VIEW PARK
PWSID: MT0002996
320 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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