Water Hardness in 15902
Johnstown, Pennsylvania · Cambria County
Dataset updated March 9, 2026Matched to 6 water systemsTap readings can vary by utility zone, treatment, and plumbing. Methodology
How this ZIP reading is built
This ZIP reading is built from 6 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 15902
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 |
|---|---|---|---|
| Greater Johnstown Wa Riverside PA4110034 | surface water | 351 PPM Very Hard | |
| Highland S & W Auth Beaverdam PA4110017 | surface water | 316 PPM Very Hard | |
| Southwestern Cambria Cnty Auth PA4110041 | surface water | 316 PPM Very Hard | |
| Reade Twp Muni Auth PA4110297 | groundwater | 351 PPM Very Hard | |
| Blacklick Valley Muni Auth PA4110077 | surface water | 351 PPM Very Hard |
Nearby Zip Codes
What This Means For You
Use this ZIP reading as a local planning estimate, not a final treatment specification. Hardness can vary by utility zone, seasonal blend, private well, and building plumbing. Confirm your tap reading with a utility report or home hardness test before sizing equipment.
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 Johnstown, PA (15902).
Frequently Asked Questions
Is the water hard in Johnstown, PA (15902)?
The average water hardness in 15902 is 339 PPM (19.8 GPG), which is classified as very hard.
Do I need a water softener in 15902?
With hardness of 339 PPM, a water softener is recommended for homes in 15902.
Is hard water in 15902 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 15902?
Zip code 15902 in Johnstown, Pennsylvania is served by 6 water systems.
Learn More About Your Water
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