Del Oro Wc - Arbuckle District, CA
Lead reported as not detected
Latest 90th-percentile lead: reported as 0 (not detected) (monitoring period 2024-2026). 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 Del Oro Wc - Arbuckle District
Del Oro Wc - Arbuckle District serves about 185 people through 56 service connections, which makes it a very small system under EPA's size classes. It is privately owned and draws groundwater, in Colusa County, California. EPA system ID: CA0605011; phone on file: 530-809-3970. Call that number and ask whether your address has a lead, galvanized or unknown service line.
Lead results over time
That is down 2.98 ppb from 2.98 ppb in the period ending 2023. The highest 90th-percentile result EPA holds for Del Oro Wc - Arbuckle District is 14.8 ppb across 5 monitoring periods, none of them over 15 ppb (1 over 10 ppb).
| Period ending | 90th-percentile lead |
|---|---|
| 2026 | 0 (not detected) |
| 2023 | 2.98 ppb |
| 2022 | 14.8 ppb over 10 |
| 2019 | 0 (not detected) |
| 2017 | 3.94 ppb |
Against other California systems
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. Del Oro Wc - Arbuckle District's reported as 0 (not detected) sits at the 26th percentile in California and the 14th 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 Del Oro Wc - Arbuckle District. 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 |
| City Of Williams | 5,538 | 0 (not detected) |
| 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 |
| Colusa Co. Service Area #2-Stonyford | 160 | 0 (not detected) |
Next steps for Chico, CA
Look up your address in Del Oro Wc - Arbuckle District'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 Del Oro Wc - Arbuckle District 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. What a 90th-percentile result does and does not tell you: how to read a lead result. A zero today does not rule out a jump later - the rules are tightening in 2027.