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ZIP Code 59840 Water Quality
Montana · 6,458 people served · 10 water systems
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ExcellentZIP code 59840 is in Montana and is a small town from a drinking-water-service perspective, with 6,458 people served by 10 EPA-registered public water systems. It corresponds to HAMILTON.
Within ZIP code 59840, the EPA Safe Drinking Water Information System (SDWIS) records no health-based Maximum Contaminant Level (MCL) exceedances during the past five years across the 10 water systems serving this postal area.
Last updated: 2026-05-18 · Source: EPA SDWIS
ZIP Code Location
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Cities in ZIP 59840
Water Systems Serving 59840
ANTIGONE ACRES HOA
PWSID: MT0003003
85 served
STOCK FARM THE
PWSID: MT0003982
150 served
WARDS COVE WATER USERS
PWSID: MT0003277
45 served
PONDEROSA MOBILE HOME PARK
PWSID: MT0002131
60 served
BIG SKY TRAILER CT HAMILTON
PWSID: MT0000504
70 served
HAMILTON CITY OF
PWSID: MT0000234
5,585 served
DALY ESTATES SUBDIVISION
PWSID: MT0004517
123 served
KOOTENAI CREEK VILLAGE
PWSID: MT0004241
175 served
BITTERROOT PINES TR CT FLORENCE
PWSID: MT0002128
45 served
WILD FLOWER HOA, THE
PWSID: MT0004533
120 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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