Water Quality in Montana: Complete Guide
Everything homeowners need to know about Montana tap water - hardness, contaminants, treatment options, and costs.
Quick summary: Montana has an average water hardness of 74 PPM across 8 cities. 13% of cities have hard water above 120 PPM. PFAS contamination is detected above EPA limits in at least one city. Most households do not need water softening equipment.
Water Hardness Across Montana
Montana's water hardness ranges from 16 PPM in Missoula to 160 PPM in Helena, with a statewide average of 74 PPM. This makes Montana one of the softer-water states. The national average is approximately 120 PPM.
Most Montana cities use surface water (rivers, lakes, reservoirs), which generally has lower mineral content than groundwater.
Contaminants of Concern in Montana
PFAS: The average PFAS level across Montana cities is 1.4 ppt. Kalispell has the highest detected PFAS at 10.9 ppt, above the EPA maximum contaminant level of 4 ppt. Residents should consider a reverse osmosis or NSF P473-certified filter for drinking water.
Lead: Lead contamination comes from plumbing infrastructure, not the water source. Montana homes built before 1986 are at higher risk due to lead solder. 2 cities show lead levels above 5 ppb.
Do You Need a Water Softener in Montana?
For most Montana residents, no. Only 13% of cities have hard water above 120 PPM. However, individual situations vary - check your city page for specific data.
Impact of Hard Water in Montana
With an average hardness of 74 PPM, most Montana households do not face significant hard water impact. However, homes with hardness above 120 PPM should evaluate treatment options.