Water Hardness by ZIP Code in
California
Browse 6 local reports across California, compare average hardness levels, and spot the cities where hard water is most likely to be a real household problem.
State summary
California
Avg. Hardness
237 PPM
State Risk
Severe
Local reports by city and ZIP code
Open a local page to see the reading, compare nearby ZIP codes, and get a plain-English interpretation.
6 REGIONS
Beverly Hills
Zip Code: 90210
Los Angeles
Zip Code: 90001
Sacramento
Zip Code: 95801
San Diego
Zip Code: 92101
San Francisco
Zip Code: 94102
San Francisco
Zip Code: 94101
Regional Water Variations
Water hardness often changes from one municipal source to the next in California, so nearby ZIP codes can tell a very different story.
Why compare? A state average can hide local hotspots where scale risk is much higher.
Priority Zones To Audit First
These ZIP codes show the highest recorded hardness in California and are usually the best places to start if you are researching treatment urgency.