Water Hardness in Hillsborough, CA
California · 1 zip codes · 25 water systems
9 PPM
0.5 GPG
Soft0Soft60120180300+
Verified — State Lab Tested
City avg (weighted): 119 PPM
Based on laboratory testing of treated tap water reported to state regulators. Updated periodically with the latest compliance data.
Primary Water System
Sfpuc City Distribution Division
CA3810011
9 PPM
0.5 GPG · Soft
Verified — State Lab Tested
USGS environmental estimate: 208 PPM
Serves: 848,019
What This Means For You
Your Water Is Soft
Your water hardness is in the soft range. You likely don't need a water softener. Enjoy your naturally soft 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 Hillsborough, CA.
Water Systems in Hillsborough
Zip Codes in Hillsborough, CA
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