Water Hardness in 59457
Lewistown, Montana · Fergus County
Dataset updated March 9, 2026Matched to 4 water systemsTap readings can vary by utility zone, treatment, and plumbing. Methodology
How this ZIP reading is built
This ZIP reading is built from 4 matched water systems. When more than one system is matched, the displayed value is weighted toward larger known service populations when that data is available.
Hardness is a mineral-content reading, not a drinking-water safety rating. Use it for scale, appliance, and softener decisions; check your utility report or test your tap before sizing treatment equipment. See how we calculate local readings.
Water Systems Serving 59457
These are the systems matched to this ZIP code. The displayed ZIP value is weighted toward larger known service populations when population data is available.
| Water System | Source | Hardness | Pop. Served |
|---|---|---|---|
Lewistown City Of MT0000271 | groundwater | 759 PPM Very Hard | |
King Ranch Colony MT0000432 | groundwater | 759 PPM Very Hard | |
Deerfield Hutterite Colony MT0000431 | groundwater | 759 PPM Very Hard | |
Spring Creek Colony Lewistown MT0000433 | groundwater | 759 PPM Very Hard |
Nearby Zip Codes
What This Means For You
Recommendations are based on the displayed ZIP hardness reading. Confirm your tap reading before sizing or buying treatment equipment.
Very Hard Water - Treatment Strongly Recommended
Your water is very hard. Without treatment, you can expect significant scale buildup in pipes and appliances, higher energy bills from reduced water heater efficiency, and persistent issues with skin and hair dryness.
Recommended Products
Learn more: Do I Need a Water Softener? | Salt-Based vs Salt-Free | Size Calculator | How to Test Your Water
Know your water hardness?
If you've tested your water or have your utility's CCR report, share your reading to help us improve accuracy for Lewistown, MT (59457).
Frequently Asked Questions
Is the water hard in Lewistown, MT (59457)?
Our estimate for 59457 is 759 PPM (44.4 GPG), but it is based on nearby, county, or state-level data rather than a direct treated tap-water report for this exact location. Confirm with your utility or a home test.
Do I need a water softener in 59457?
Do not size a softener from this estimate alone. Confirm the actual tap-water hardness before choosing treatment equipment.
Is hard water in 59457 safe to drink?
Water hardness itself is a mineral-content reading, not a drinking-water safety rating. Calcium and magnesium are naturally occurring minerals, but you should check your utility's Consumer Confidence Report for contaminant and compliance information.
How many water systems serve 59457?
Zip code 59457 in Lewistown, Montana is served by 4 water systems.
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