City Of Williams, CA
Lead reported as not detected
Latest 90th-percentile lead: reported as 0 (not detected) (monitoring period 2021-2023). 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.
About City Of Williams
City Of Williams serves about 5,538 people through 1,565 service connections, which makes it a medium-sized system under EPA's size classes. It is owned by a local government (city, town, county or district) and draws groundwater, in Colusa County, California. EPA system ID: CA0610004; phone on file: 530-908-0407. They can tell you what your service line is made of and whether they pay to replace it.
Lead results over time
Against the period ending 2020 (0 ppb) the latest result is about the same. The highest 90th-percentile result EPA holds for City Of Williams is 0 ppb across 3 monitoring periods, none of them over 15 ppb.
| Period ending | 90th-percentile lead |
|---|---|
| 2023 | 0 (not detected) |
| 2020 | 0 (not detected) |
| 2017 | 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. City Of Williams's reported as 0 (not detected) sits at the 50th percentile in California and the 35th nationally (higher means more lead). Systems reporting 0 tie at the bottom, so the rank mostly reflects size among them.
Other water systems in Colusa County
8 other systems share Colusa County; 4 of them have a higher latest lead result than City Of Williams. If you are unsure which one supplies your house, the name on your water bill decides it.
| System | People | Latest lead |
|---|---|---|
| City Of Colusa | 6,675 | 6.8 ppb |
| Arbuckle Public Utility District | 3,251 | 0 (not detected) |
| Maxwell Public Utility District | 1,175 | 0.98 ppb |
| Colusa Co. Wwd #1 - Grimes | 512 | 5.77 ppb |
| Colusa Co. Service Area #1-Century Ranch | 450 | 0 (not detected) |
| Colusa Co. Wwd #2 - Princeton | 382 | 1.3 ppb |
| Del Oro Wc - Arbuckle District | 185 | 0 (not detected) |
| Colusa Co. Service Area #2-Stonyford | 160 | 0 (not detected) |
Next steps for Williams, CA
Look up your address in City Of Williams'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 City Of Williams 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. A zero today does not rule out a jump later - the rules are tightening in 2027.