Water Hardness in 94128
San Francisco, California · San Mateo County
Based on laboratory testing of treated tap water reported to state regulators. Updated periodically with the latest compliance data.
Our Estimate
Weighted average from 18 water systems.
What This Means For You
Hard Water - Treatment Recommended
Your water is hard. Scale buildup is likely affecting your plumbing and appliances, reducing their lifespan and efficiency. A water softener is recommended to protect your home.
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 San Francisco, CA (94128).
Water Systems Serving 94128
Nearby Zip Codes
Frequently Asked Questions
Is the water hard in San Francisco, CA (94128)?
The average water hardness in 94128 is 241 PPM (14.1 GPG), which is classified as hard.
Do I need a water softener in 94128?
With hardness of 241 PPM, a water softener is recommended for homes in 94128.
How many water systems serve 94128?
Zip code 94128 in San Francisco, California is served by 18 water systems.
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