Is Windsor, 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 Town of Windsor.
Town of Windsor supplies Windsor (25,561 people).
Water system
Town of Windsor
25,561 people · Groundwater · EPA ID CA4910017
Buys treated water from Sonoma County Water Agency.
| PFAS | Highest average | Limit |
|---|---|---|
| PFOA Not detected | – | 4 ppt |
| PFOS Not detected | – | 4 ppt |
| PFHxS Not detected | – | 10 ppt |
| PFNA Not detected | – | 10 ppt |
| HFPO-DA (GenX) Not detected | – | 10 ppt |
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 2025, and 9 in 10 homes sampled were at or below it) Below action level
Health-based violations since 2016: 0
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.
Windsor homes and lead pipes
Lead service lines and lead solder were allowed until 1986, so homes from before then are the ones to check. How to check your own line.
Housing: Census American Community Survey 2020–2024 5-year estimates for Windsor town (tables B25034, B25003). Estimates for small places have a margin of error.
How nearby cities compare
| City | PFAS | Lead (90th pct.) |
|---|---|---|
| Santa Rosa 9 mi City of Santa Rosa | None above limits | 1.32 ppb |
| Rohnert Park 15 mi Marin Municipal Water District | None above limits | 0 ppb |
| Petaluma 23 mi City of Petaluma | None above limits | 0 ppb |
| Napa 32 mi City of Napa | None above limits | 0 ppb |
| Novato 35 mi Marin Municipal Water District | None above limits | 0 ppb |
| San Rafael 42 mi Marin Municipal Water District | None above limits | 0 ppb |
Windsor ZIP codes (1)
- 95492
Questions
Is Windsor tap water safe to drink?
Town of Windsor 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 Windsor, CA?
Town of Windsor, which serves 25,561 people.
Does Windsor tap water have PFAS?
None detected above EPA's reporting limits. Town of Windsor 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 Windsor homes have lead pipes?
Census estimates put 15% of Windsor 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. Town of Windsor'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.