Tap Water Results

Is San Rafael, CA tap water safe?

Data: U.S. EPA · How we read the data · How we check it

Summary

No federal limits exceeded in EPA data for Marin Municipal Water District.

2 public water systems serve parts of San Rafael. The largest, Marin Municipal Water District, serves 188,116 people. Your water bill names your system.

Largest system

Marin Municipal Water District

188,116 people · Surface water · EPA ID CA2110002

Buys treated water from Sonoma County Water Agency.

PFASHighest averageLimitStatus
PFOA
Not detected
–4 pptNot detected
PFOS
Not detected
–4 pptNot detected
PFHxS
Not detected
–10 pptNot detected
PFNA
Not detected
–10 pptNot detected
HFPO-DA (GenX)
Not detected
–10 pptNot detected

ppt = parts per trillion. "Highest average" is the highest average at any of the system's entry points, the way EPA compares results with the limits.

Lead: 0 ppb at the 90th percentile (Dec 2021, and 9 in 10 homes sampled were at or below it) Below action level
Health-based violations since 2016: 0

Full Marin Municipal Water District results

Across California, 129 of 691 water systems EPA tested had PFAS above a 2024 federal limit, and 26 systems were above the lead action level in results from the last five years. California results.

San Rafael homes and lead pipes

71%
of homes built before 1980 (California 56%, US 50%)
15%
built before 1950 (California 14%)
47%
of households rent (California 44%)

Lead service lines and lead solder were allowed until 1986, so homes from before then are the ones to check. Renting? Ask your landlord what the service line is made of, because it's their pipe to replace. How to check your own line.

Housing: Census American Community Survey 2020–2024 5-year estimates for San Rafael city (tables B25034, B25003). Estimates for small places have a margin of error.

Other water systems serving San Rafael

  • Kohala Ranch Water Company
    850 people · Groundwater · Hawaii · reported ZIPs here
    Lead near 2027 level

How nearby cities compare

CityMain water systemPFASLead (90th pct.)
Novato 8 mi
Marin Municipal Water District
Marin Municipal Water DistrictNone above limits0 ppb
Richmond 8 mi
East Bay Municipal Utility District
East Bay Municipal Utility DistrictNone above limits0 ppb
El Cerrito 12 mi
East Bay Municipal Utility District
East Bay Municipal Utility DistrictNone above limits0 ppb
Hercules 12 mi
East Bay Municipal Utility District
East Bay Municipal Utility DistrictNone above limits0 ppb
Berkeley 14 mi
East Bay Municipal Utility District
East Bay Municipal Utility DistrictNone above limits0 ppb
Vallejo 16 mi
City of Vallejo
City of VallejoNone above limits0 ppb
San Rafael ZIP codes (2)
  • 94901
  • 94903

Questions

Is San Rafael tap water safe to drink?

Marin Municipal Water District has had no health-based violations since 2016. Utility data can't show lead from your own pipes: if your home was built before 1986, test your tap. Your utility's annual Consumer Confidence Report is the official summary.

Who supplies water in San Rafael, CA?

2 public water systems serve parts of San Rafael. The largest is Marin Municipal Water District (188,116 people). Your water bill names your system. The EPA ID is also on your utility's Consumer Confidence Report.

Does San Rafael tap water have PFAS?

None detected above EPA's reporting limits. Marin Municipal Water District had no PFAS detected in EPA's 2023–2025 testing. "Not detected" means below the reporting limit (about 2 to 20 ppt), not proven zero.

Do San Rafael homes have lead pipes?

Census estimates put 71% of San Rafael homes as built before 1980 (California: 56%). Lead service lines and lead solder were allowed until 1986, so older homes are more likely to have them. Marin Municipal Water District's service line inventory says what your line is made of. The only way to know for your home is to check the line where it enters the house and test your tap.

Source: U.S. EPA drinking water records and PFAS testing (UCMR 5). How we read the data.