Great Falls
Great Falls, MT water profile — supply sources, drought status, wastewater reuse, and the key water issues facing the city.
great falls city of
surface water (rivers/reservoirs) · local government · PWSID MT0000525
Below EPA's 15 ppb lead action level at last testing.
Source: EPA Safe Drinking Water Information System (SDWIS) · 2026 Q1
Great Falls is a small but growing city and the 3rd-largest in Montana, home to roughly 59,638 residents. Great Falls's drinking water comes largely from the same regional sources that serve Montana: Missouri River headwaters, snowpack, and aquifers.
As elsewhere in Montana, the central challenge is agricultural demand. Irrigation dominates use; shrinking snowpack affects downstream timing across the Missouri basin.
Montana reuses an estimated 3% of its treated wastewater and maintains minimal reuse programs; Great Falls tracks severe to extreme drought conditions on the U.S. Drought Monitor scale.
Explore the Montana profile for statewide context, or dig into the water issues shaping Great Falls below.
Cascade County water quality
Source: EPA SDWIS · 2026 Q1
At a glance
- Population ~59,638 (3rd-largest in Montana)
- Primary sources: Missouri River headwaters, snowpack, and aquifers
- Drought: severe to extreme conditions
- State reuse rate: ~3% of wastewater
Statewide drought history
% of Montana in severe+ drought (Extreme (D3) now).
Source: U.S. Drought Monitor
Common questions
Is tap water safe in Great Falls?
Great Falls's largest water system, GREAT FALLS CITY OF, serves about 60,000 people. EPA records show 5 health-based violation(s) since 2016 and a most-recent 90th-percentile lead level of 12 ppb (EPA action level is 15 ppb). Always check your own provider's annual Consumer Confidence Report.
Where does Great Falls get its water?
GREAT FALLS CITY OF draws primarily from surface water (rivers/reservoirs), part of Montana's supply from Missouri River headwaters, snowpack, aquifers.
Related water issues
Agricultural Demand
Agriculture accounts for the majority of consumptive water use in the West, making farm efficiency and water markets central to any supply solution.
ExploreDrought
Much of the American West is in a multi-decade dry period that researchers describe as the most severe in over a millennium, reshaping how communities plan for water.
Explore