County · Montana
Lake County, Montana: drinking water records
This overview covers 12 ZIP codes and 26 community water systems in Lake County. It also stands in for 3 ZIP codes whose utility has too little EPA data for a page of its own.
System population figures are summed from EPA registry records and can overlap where wholesalers and retail systems serve the same people. They are not a Census county-population estimate.
Water systems with the most complete records
| Water system | People served | PFAS survey results | PFAS found | Health-based violations | Lead, 9 in 10 homes at or below |
|---|---|---|---|---|---|
| Polson City of MT0000308 | 5,300 | 300 | 0 | 0 | 2 ppb |
| Pablo Lake County Water and Sewer Dist MT0001917 | 2,175 | 0 | 0 | 2 | 3 ppb |
| St Ignatius Town of MT0001740 | 700 | 0 | 0 | 1 | 1 ppb |
| Mission Mountain View HOA MT0003157 | 80 | 0 | 0 | 1 | 0 ppb |
| Ronan City of MT0000318 | 2,483 | 0 | 0 | 0 | 0 ppb |
| Woods Bay Water and Sewer District MT0004698 | 685 | 0 | 0 | 0 | 4 ppb |
| Consolidated Charlo Lake Co W and S Dist MT0000172 | 450 | 0 | 0 | 0 | 0 ppb |
| Round Butte Water Company MT0000320 | 400 | 0 | 0 | 0 | 2 ppb |
| Jette Meadows Lake Co W and S Dist MT0003100 | 375 | 0 | 0 | 0 | 1 ppb |
| Jette Lake Landowners Association MT0003102 | 295 | 0 | 0 | 0 | 0 ppb |
| Ridgewood Estates MT0003175 | 250 | 0 | 0 | 0 | 2 ppb |
| Mission Meadows RV Campsite Park, INC MT0000621 | 200 | 0 | 0 | 0 | 0 ppb |
| Conway Commons Mobile Home Park MI0040126 | 165 | 0 | 0 | 0 | 2.1 ppb |
| Mission Mountain Lake Co W and S Dist MT0003801 | 118 | 0 | 0 | 0 | 0 ppb |
| Paradise Pines MT0001018 | 95 | 0 | 0 | 0 | 3 ppb |
| Clearview Heights Lake County Water Dist MT0003233 | 90 | 0 | 0 | 0 | 0 ppb |
| Christian Childrens Ranch MT0003720 | 65 | 0 | 0 | 0 | 1 ppb |
| South Hills Water Users Association MT0003104 | 60 | 0 | 0 | 0 | 0 ppb |
| Shelter Bay Estates MT0003376 | 56 | 0 | 0 | 0 | 1 ppb |
| Kootenai Woods Subdivision MT0004400 | 53 | 0 | 0 | 0 | 0 ppb |
| Crane Mountain Estates MT0004884 | 50 | 0 | 0 | 0 | 3 ppb |
| Stone Ridge Water Company MT0004605 | 50 | 0 | 0 | 0 | 0 ppb |
| Overlook Subdivision MT0003792 | 49 | 0 | 0 | 0 | 0 ppb |
| Pinewood Shores Wua MT0003224 | 46 | 0 | 0 | 0 | 5 ppb |
| Pleasant View Water and Sewer District MT0004671 | 45 | 0 | 0 | 0 | 1 ppb |
ZIP reports in Lake County
No ZIP report in this county is published yet.
These ZIP codes are covered by this overview because their utility has too little EPA data for a separate page: 59863, 59914, 59929.
Sources and scope
EPA UCMR 5 occurrence data, samples collected 2023-01-03 – 2026-06-17, final release, August 2026 (file dated Aug 28, 2026); EPA SDWIS via ECHO, 2026Q2 extract (file dated Jul 9, 2026); EPA service-area boundaries v3.0; Census 2020 ZCTAs. Page generated 2026-09-03.
Counts cover the systems that report this county to EPA. A water system may cross county lines. "Found" means at least one result at or above the laboratory reporting level; it is not a compliance finding.