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Water Hardness in 93638

Madera, California · Madera County

244 PPM
14.3 GPG
Hard
0Soft60120180300+
High Confidence — USGS Monitoring

Dataset updated March 9, 2026Matched to 6 water systemsTap readings can vary by utility zone, treatment, and plumbing. Methodology

Source context

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.

Source basis
4 USGS-backed sources
6 matched systems total for this ZIP; USGS monitoring is used where treated-water reports are unavailable.
Water source profile
Primarily groundwater
Groundwater commonly picks up calcium and magnesium after contact with rock and soil. This profile is weighted by known population served across matched systems.
Data recency
March 9, 2026
Dataset rebuilt March 9, 2026; individual utility reporting years can vary.

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 93638

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.

6 water systems
PWSID is the public water system identifier. Data Source shows whether the hardness value comes from a treated-water report, USGS monitoring, or a local estimate; source year is shown when available.
City Of Madera
CA2010002
Very Hard
261 PPMgroundwater66,560 servedHigh Confidence — USGS Monitoring
Chowchilla City Water Dept
CA2010001
Very Hard
261 PPMgroundwater13,916 servedHigh Confidence — USGS Monitoring
Madera Valley Water Company
CA2010010
Slightly Hard
84 PPMgroundwater6,494 servedHigh Confidence — USGS Monitoring
Riverstone/Rootcreek Water District
CA2010016
Very Hard
261 PPMgroundwater5,507 servedEstimated — County Avg
Central Ca Womens Facility
CA2010800
Soft
56 PPMgroundwater2,183 servedHigh Confidence — USGS Monitoring
Showing the first 5 systems. Expand to review all matched systems.

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.

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 (93638).

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Frequently Asked Questions

Is the water hard in Madera, CA (93638)?

The average water hardness in 93638 is 244 PPM (14.3 GPG), which is classified as hard.

Do I need a water softener in 93638?

With hardness of 244 PPM, a water softener is recommended for homes in 93638.

Is hard water in 93638 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 93638?

Zip code 93638 in Madera, California is served by 6 water systems.

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