County · Montana
Chouteau County, Montana: drinking water records
This overview covers 7 ZIP codes and 12 community water systems in Chouteau County. It also stands in for 1 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 |
|---|---|---|---|---|---|
| Geraldine Town of MT0000225 | 260 | 0 | 0 | 2 | 3 ppb |
| Carter Chouteau Co Water Dist MT0000520 | 150 | 0 | 0 | 1 | 0 ppb |
| South Chouteau County Water Dist MT0001925 | 80 | 0 | 0 | 1 | 2 ppb |
| Twin Hills Colony INC MT0003978 | 78 | 0 | 0 | 8 | 0 ppb |
| Fort Benton City of MT0000216 | 1,500 | 0 | 0 | 0 | 2 ppb |
| Big Sandy Town of MT0000150 | 608 | 0 | 0 | 0 | 0 ppb |
| Highwood County Water and Sewer District MT0000248 | 280 | 0 | 0 | 0 | 5 ppb |
| Loma County Water District MT0002669 | 200 | 0 | 0 | 0 | 1 ppb |
| Guernsey Lake Mobile Home Community MI0040046 | 100 | 0 | 0 | 2 | not reported |
| Sunny Brook Colony MT0005121 | 80 | 0 | 0 | 0 | 0 ppb |
| Hawarden Square Butte Water MT0003522 | 50 | 0 | 0 | 0 | 2 ppb |
| North Geraldine Water System MT0003521 | 50 | 0 | 0 | 0 | 0 ppb |
ZIP reports in Chouteau 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: 59440.
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.