Tiburon, CA water hardness
Reported by Marin Municipal Water District · October 2025
- CA typical
- 121 mg/L
- EPA health violations since 2016
- 0
- Data
- Utility report
Tiburon water measures 56 mg/L (3.3 gpg) of hardness, soft by USGS standards. The number comes from Marin Municipal Water District, dated October 2025.
Tiburon sits 65 mg/L below the typical California figure of 121. None of the 10 nearest cities we track has harder water. The range nearby runs from 34 mg/L in Richmond to 56 in Sausalito.
What 56 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 56 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 Tiburon's water system
No health-based violations since 2016
Serves about 188,116 people from surface water.
- Health-based
- 0
- Monitoring or reporting
- 0
- Open now
- 0
TapWaterData ties Tiburon to this system. EPA's service-area records do not name Tiburon, 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 Tiburon water hard?
No. It measures about 56 mg/L (3.3 grains per gallon), which the USGS classes as soft.
What is the water hardness in Tiburon in grains per gallon?
About 3.3 gpg. One grain per gallon equals 17.1 mg/L, so 56 mg/L divided by 17.1 gives 3.3.
Has the Tiburon water system had EPA violations?
EPA records show no health-based violations for Marin Municipal Water District since 2016.
Nearby cities
- Sausalito56 mg/LSoft
- Strawberry56 mg/LSoft
- Corte Madera56 mg/LSoft
- Tamalpais-Homestead Valley56 mg/LSoft
- Mill Valley56 mg/LSoft
- Larkspur56 mg/LSoft
- Kentfield56 mg/LSoft
- San Rafael56 mg/LSoft
- Richmond34 mg/LSoft
- Albany34 mg/LSoft
Hardness data: TapWaterData US Water Hardness (utility report, October 6, 2025), CC BY 4.0. Population: US Census Bureau. Violations: EPA ECHO. How we use them.