Windsor, Town Of, CA
Lead reported as not detected
Latest 90th-percentile lead: reported as 0 (not detected) (monitoring period 2023-2025). The federal action level is 15 ppb today and drops to 10 ppb in Nov 2027; EPA's health goal is 0. The latest 90th-percentile result was reported as 0 (not detected at the lab's limit). That says the sampled homes were low, not that your home has no lead service line. Check your utility's service line inventory for your address.
Windsor, Town Of at a glance
Windsor, Town Of serves about 25,561 people through 9,109 service connections, which makes it a large system under EPA's size classes. It is owned by a local government (city, town, county or district) and draws groundwater, in Sonoma County, California. EPA system ID: CA4910017; phone on file: 707-838-5309. Call that number and ask whether your address has a lead, galvanized or unknown service line.
Every lead result on file
Against the period ending 2022 (0 ppb) the latest result is about the same. The highest 90th-percentile result EPA holds for Windsor, Town Of is 0 ppb across 4 monitoring periods, none of them over 15 ppb.
| Period ending | 90th-percentile lead |
|---|---|
| 2025 | 0 (not detected) |
| 2022 | 0 (not detected) |
| 2019 | 0 (not detected) |
| 2016 | 0 (not detected) |
Where this result ranks
Of the 2,884 California systems with a lead result, the median latest reading is 0 ppb; 30 are over 15 ppb right now and 215 have gone over at some point. Windsor, Town Of's reported as 0 (not detected) sits at the 56th percentile in California and the 39th nationally (higher means more lead). Systems reporting 0 tie at the bottom, so the rank mostly reflects size among them.
Nearby utilities
128 other systems share Sonoma County; 24 of them have a higher latest lead result than Windsor, Town Of. If you are unsure which one supplies your house, the name on your water bill decides it.
| System | People | Latest lead |
|---|---|---|
| Santa Rosa, City Of | 178,452 | 1.32 ppb |
| Petaluma, City Of | 61,427 | 0 (not detected) |
| Rohnert Park, City Of | 43,821 | 0 (not detected) |
| Valley Of The Moon Water District | 23,140 | 0 (not detected) |
| Healdsburg, City Of | 10,972 | 0 (not detected) |
| Sonoma, City Of | 10,619 | 0 (not detected) |
| Cloverdale, City Of | 8,710 | 0 (not detected) |
| California-American Larkfield (Puc) | 7,911 | 6 ppb |
| Sebastopol, City Of | 7,522 | 0 (not detected) |
| Cotati, City Of | 7,290 | 0 (not detected) |
Next steps for Windsor, CA
Look up your address in Windsor, Town Of's service line inventory. If it says lead, galvanized or unknown, test your tap. If your own line is lead, replacing the private side runs about $1,200-$12,300 (EPA average about $4,700). Ask Windsor, Town Of whether it covers that cost before hiring anyone - many utilities now do.
These figures describe homes the utility sampled, not your tap. Only your service line record or a test of your own water answers the question for your house. The lead result guide covers how utilities pick the homes they sample. Small systems behave differently: why small systems go over more often.