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ZIP Code 59923 Water Quality
Montana · 5,568 people served · 9 water systems
F
FailingZIP code 59923 is in Montana and is a small town from a drinking-water-service perspective, with 5,568 people served by 9 EPA-registered public water systems. It corresponds to LIBBY.
Within ZIP code 59923, the EPA Safe Drinking Water Information System (SDWIS) records 11 health-based violations during the past five years across 9 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 59923
Water Systems Serving 59923
MONTANA CHRISTIAN COLLEGE
PWSID: MT0004270
105 served
PINEWOOD VILLAGE
PWSID: MT0000275
160 served
RIVERS EDGE MOBILE PARK LIBBY
PWSID: MT0000553
60 served
JOHNSONS MOBILE HOME PARK
PWSID: MT0000529
35 served
LIBBY CREEK MOBILE PARK LLC-UNAPPROVED
PWSID: MT0005241
35 served
EMKAYAN VILLAGE CO WATER AND SEWER DIST
PWSID: MT0000540
160 served
POSTS TRAILER COURT
PWSID: MT0000554
45 served
HIGH COUNTRY PARK
PWSID: MT0001850
76 served
LIBBY CITY OF
PWSID: MT0000274
4,892 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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