118 cities covered
Montana water quality, by city
Montana cities of 10,000+
| City | Disinfectant | Hardness | Lead | PFAS | Radon |
|---|---|---|---|---|---|
| Billings | Chlorine | 9.3 gpg | 3 ppb | Not detected | Moderate |
| Missoula | Chlorine | 6.8 gpg | 2 ppb | Not detected | High |
| Great Falls | Chloramine | No data | 12 ppb | Not detected | High |
| Bozeman | Chlorine | 5.4 gpg | 1.6 ppb | Not detected | High |
| Helena | Chlorine | No data | 3 ppb | Not detected | High |
| Kalispell | Chlorine | 12.0 gpg | 2 ppb | PFOS | High |
| Belgrade | Not confirmed | 13.2 gpg | 1.8 ppb | Not detected | High |
Smaller Montana towns
111 more covered towns, each with its own page.
- Alberton
- Anaconda-Deer Lodge County
- Bainville
- Baker
- Bearcreek
- Belt
- Big Sandy
- Big Timber
- Boulder
- Bridger
- Broadus
- Broadview
- Cascade
- Chester
- Chinook
- Choteau
- Circle
- Clyde Park
- Colstrip
- Columbia Falls
- Columbus
- Conrad
- Culbertson
- Cut Bank
- Darby
- Deer Lodge
- Denton
- Dillon
- Dodson
- Drummond
- Dutton
- East Helena
- Ekalaka
- Ennis
- Eureka
- Fairfield
- Fairview
- Forsyth
- Fort Benton
- Fort Peck
- Froid
- Fromberg
- Geraldine
- Glasgow
- Glendive
- Grass Range
- Hamilton
- Hardin
- Harlem
- Harlowton
- Havre
- Hingham
- Hobson
- Hot Springs
- Hysham
- Joliet
- Jordan
- Judith Gap
- Kevin
- Laurel
- Lewistown
- Libby
- Lima
- Livingston
- Lodge Grass
- Malta
- Manhattan
- Medicine Lake
- Melstone
- Miles City
- Moore
- Nashua
- Philipsburg
- Pinesdale
- Plains
- Plentywood
- Plevna
- Polson
- Poplar
- Red Lodge
- Richey
- Ronan
- Roundup
- Ryegate
- Saco
- Scobey
- Shelby
- Sheridan
- Sidney
- St. Ignatius
- Stanford
- Stevensville
- Sunburst
- Superior
- Thompson Falls
- Three Forks
- Townsend
- Troy
- Twin Bridges
- Valier
- Virginia City
- Walkerville
- West Yellowstone
- Westby
- White Sulphur Springs
- Whitefish
- Whitehall
- Wibaux
- Winifred
- Winnett
- Wolf Point
What the data shows across Montana
Chlorine or chloramine
11 of 118 covered cities use chloramine in at least part of the system: Great Falls, Wolf Point, Plentywood, Scobey, Poplar, Culbertson and 5 more. Most cheap shower filters barely affect chloramine; look for vitamin C or catalytic carbon media.
Shower filters that handle chloramineHardness
3 of 5 cities with a hardness reading have hard or very hard water. Readings run from 5.4 grains per gallon in Bozeman (moderately hard) to 13.2 in Belgrade (very hard).
Softener or filter?Lead
9 cities' utilities reported a 90th-percentile lead result of 5 ppb or more: Great Falls, Anaconda-Deer Lodge County, Glendive, Glasgow, Fromberg, Dutton and 3 more. Lead comes from service lines and plumbing, so a home test is the reading that counts.
PFAS
EPA's nationwide sampling found PFAS above a 2024 EPA limit, in at least one sample, in the water serving Kalispell, and below the limits in 1 more.
Health-based violations
32 of 118 covered cities' utilities had a health-based EPA violation since 2016: Great Falls, Helena, Havre, Miles City, Laurel, Lewistown and 26 more. Each city page lists the contaminants.