Water Hardness in 95421
Cazadero, California · Sonoma County
Dataset updated March 9, 2026Matched to 14 water systemsTap readings can vary by utility zone, treatment, and plumbing. Methodology
How this ZIP reading is built
This ZIP reading is built from 14 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 95421
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 |
|---|---|---|---|
Santa Rosa, City Of CA4910009 | groundwater | 129 PPM Moderately Hard | |
Petaluma, City Of CA4910006 | groundwater | 98 PPM Slightly Hard | |
Rohnert Park, City Of CA4910014 | groundwater | 158 PPM Moderately Hard | |
Windsor, Town Of CA4910017 | groundwater | 129 PPM Moderately Hard | |
Valley Of The Moon Water District CA4910013 | groundwater | 129 PPM Moderately 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.
Moderately Hard Water
Your water is moderately hard. You're likely seeing scale buildup on fixtures, spotty dishes, and may notice dry skin or hair. A water softener or conditioner can help.
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 Cazadero, CA (95421).
Frequently Asked Questions
Is the water hard in Cazadero, CA (95421)?
The average water hardness in 95421 is 126 PPM (7.4 GPG), which is classified as moderately hard.
Do I need a water softener in 95421?
With hardness of 126 PPM, a water softener is worth considering for homes in 95421.
Is hard water in 95421 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 95421?
Zip code 95421 in Cazadero, California is served by 14 water systems.
Learn More About Your Water
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Salt-based softeners remove hardness minerals. Salt-free conditioners prevent scale but don't soften. Here's how to choose based on your water hardness level.
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