Water Hardness in 93637
Madera, California · Madera County
Dataset updated March 9, 2026Matched to 25 water systemsTap readings can vary by utility zone, treatment, and plumbing. Methodology
How this ZIP reading is built
This ZIP reading is built from 25 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 93637
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 |
|---|---|---|---|
| City Of Madera CA2010002 | groundwater | 261 PPM Very Hard | |
| Chowchilla City Water Dept CA2010001 | groundwater | 261 PPM Very Hard | |
| Riverstone/Rootcreek Water District CA2010016 | groundwater | 261 PPM Very Hard | |
| Madera Co Md10A-Madera Ranchos CA2010008 | groundwater | 261 PPM Very Hard | |
| Central Ca Womens Facility CA2010800 | groundwater | 56 PPM Soft |
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 Madera, CA (93637).
Frequently Asked Questions
Is the water hard in Madera, CA (93637)?
The average water hardness in 93637 is 257 PPM (15 GPG), which is classified as very hard.
Do I need a water softener in 93637?
With hardness of 257 PPM, a water softener is recommended for homes in 93637.
Is hard water in 93637 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 93637?
Zip code 93637 in Madera, California is served by 25 water systems.
Learn More About Your Water
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