San Leandro, CA water hardness
Reported by East Bay MUD · October 2025
- CA typical
- 121 mg/L
- EPA health violations since 2016
- 0
- Data
- Utility report
San Leandro water measures 34 mg/L (2.0 gpg) of hardness, soft by USGS standards. The number comes from East Bay MUD, dated October 2025. Reports for this system disagree, with values from 16 to 34 mg/L.
San Leandro sits 87 mg/L below the typical California figure of 121. Of the 10 nearest cities we track, 4 have softer water and 1 has harder. The range nearby runs from 33 mg/L in San Lorenzo to 44 in Hayward.
What 34 mg/L means at home
Soap and shampoo lather with very little product. Kettles and showerheads stay mostly free of white crust.
Some people notice that soap feels slow to rinse off in soft water. That slippery feel is normal and harmless.
Hardness is not a health problem, and EPA sets no limit for it. It is a matter of scale and soap.
What to do about it
Nothing, as far as hardness goes. At 34 mg/L a softener would have almost nothing to remove.
Carbon filter
If the water tastes of chlorine, a pitcher or faucet carbon filter takes care of that. It does not change hardness.
EPA record for San Leandro's water system
No health-based violations since 2016
Serves about 1,468,000 people from surface water.
- Health-based
- 0
- Monitoring or reporting
- 0
- Open now
- 0
TapWaterData ties San Leandro to this system. EPA's service-area records do not name San Leandro, so check the utility printed on your water bill.
Health-based means a contaminant above its legal limit or a missed treatment step. Monitoring and reporting violations are late or missing tests and notices. Source: EPA ECHO, 2026Q3 export, violations with periods starting 2016 or later. Full EPA record.
Questions
Is San Leandro water hard?
No. It measures about 34 mg/L (2.0 grains per gallon), which the USGS classes as soft.
What is the water hardness in San Leandro in grains per gallon?
About 2.0 gpg. One grain per gallon equals 17.1 mg/L, so 34 mg/L divided by 17.1 gives 2.0.
Has the San Leandro water system had EPA violations?
EPA records show no health-based violations for East Bay MUD since 2016.
Nearby cities
- San Lorenzo33 mg/LSoft
- Ashland33 mg/LSoft
- Cherryland33 mg/LSoft
- Castro Valley34 mg/LSoft
- Oakland34 mg/LSoft
- Alameda34 mg/LSoft
- Hayward44 mg/LSoft
- Fairview33 mg/LSoft
- Piedmont34 mg/LSoft
- Moraga34 mg/LSoft
Hardness data: TapWaterData US Water Hardness (utility report, October 13, 2025), CC BY 4.0. Population: US Census Bureau. Violations: EPA ECHO. How we use them.