County · Montana
Cascade County, Montana: drinking water records
This overview covers 15 ZIP codes and 41 community water systems in Cascade County. It also stands in for 2 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 |
|---|---|---|---|---|---|
| Great Falls City of MT0000525 | 60,000 | 120 | 0 | 5 | 12 ppb |
| Malmstrom Air Force Base MT0000515 | 8,850 | 240 | 1 | 2 | 0 ppb |
| Sun Prairie Village County MT0000521 | 1,800 | 60 | 0 | 0 | 1 ppb |
| Black Eagle Cascade County Water Sewer MT0000157 | 1,233 | 0 | 0 | 4 | 0 ppb |
| Homestead Acres County Water and Sewer MT0000526 | 500 | 0 | 0 | 1 | 0 ppb |
| Bushard Water Company MT0005164 | 425 | 0 | 0 | 1 | 0 ppb |
| Ryan Dam Water System MT0000046 | 230 | 0 | 0 | 1 | 1 ppb |
| Stockett Water and Sewer Dist MT0000579 | 210 | 0 | 0 | 1 | 1 ppb |
| Sand Coulee Water Users District MT0000325 | 180 | 0 | 0 | 1 | 3 ppb |
| Big Bend Ranch Subdivision MT0004261 | 100 | 0 | 0 | 1 | 0 ppb |
| Spring Tree Ridge MT0004419 | 80 | 0 | 0 | 1 | 0 ppb |
| Prairie Water Company MT0003539 | 1,000 | 0 | 0 | 0 | 0 ppb |
| Cascade Town of MT0000171 | 650 | 0 | 0 | 0 | 2 ppb |
| Belt Town of MT0000138 | 600 | 0 | 0 | 0 | 0 ppb |
| Vaughn Cascade County Water and Sewer MT0000352 | 585 | 0 | 0 | 0 | 0 ppb |
| Two Buttes Water Users Assn MT0000580 | 525 | 0 | 0 | 0 | 2 ppb |
| Gore Hill County Water Dist MT0000232 | 500 | 0 | 0 | 0 | 4 ppb |
| Highwood Mobile Home Park MT0004681 | 400 | 0 | 0 | 0 | 3 ppb |
| Sun Prairie Water District MT0000571 | 350 | 0 | 0 | 0 | 0 ppb |
| Neihart Town of MT0000298 | 229 | 0 | 0 | 0 | 7 ppb |
| South Wind Water and Sewer District MT0000025 | 200 | 0 | 0 | 0 | 3 ppb |
| Tracy Water Users Corp MT0000345 | 200 | 0 | 0 | 0 | 0 ppb |
| Big Stone Colony INC MT0003077 | 130 | 0 | 0 | 0 | 1 ppb |
| Pleasant Park Community INC MT0000028 | 125 | 0 | 0 | 0 | 4 ppb |
| Pleasant Valley Colony MT0003304 | 120 | 0 | 0 | 0 | 1 ppb |
ZIP reports in Cascade 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: 59443, 59483.
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.