Sullivan Mutual Water, CA
Lead reported as not detected
Latest 90th-percentile lead: reported as 0 (not detected) (monitoring period 2022-2024). 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 Sullivan Mutual Water
Sullivan Mutual Water serves about 53 people through 16 service connections, which makes it a very small system under EPA's size classes. It is privately owned and draws groundwater, in Santa Clara County, California. EPA system ID: CA4300571; phone on file: 408-529-5673. Ask them for your address in their service line inventory - every system had to publish one by Oct 2024.
Lead results over time
Against the period ending 2021 (0.8 ppb) the latest result is about the same. The highest 90th-percentile result EPA holds for Sullivan Mutual Water is 1 ppb across 3 monitoring periods, none of them over 15 ppb.
| Period ending | 90th-percentile lead |
|---|---|
| 2024 | 0 (not detected) |
| 2021 | 0.8 ppb |
| 2018 | 1 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. Sullivan Mutual Water's reported as 0 (not detected) sits at the 8th percentile in California and the 4th nationally (higher means more lead). Systems reporting 0 tie at the bottom, so the rank mostly reflects size among them.
Other water systems in Santa Clara County
72 other systems share Santa Clara County; 28 of them have a higher latest lead result than Sullivan Mutual Water. If you are unsure which one supplies your house, the name on your water bill decides it.
| System | People | Latest lead |
|---|---|---|
| San Jose Water | 1,039,920 | 0 (not detected) |
| City Of Sunnyvale | 157,566 | 0 (not detected) |
| City Of Santa Clara | 134,587 | 2.7 ppb |
| Great Oaks Wc Inc | 112,582 | 0 (not detected) |
| City Of San Jose - Evg/Edv/Coy | 99,783 | 0 (not detected) |
| City Of Milpitas | 81,915 | 2.5 ppb |
| City Of Mountain View | 81,340 | 0 (not detected) |
| City Of Palo Alto | 67,658 | 0 (not detected) |
| Cwsc Los Altos Suburban | 63,559 | 1.5 ppb |
| City Of Gilroy | 59,426 | 2 ppb |
What to do in your house
Look up your address in Sullivan Mutual Water'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 Sullivan Mutual Water 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. Small systems behave differently: why small systems go over more often.