Camp Jones Gulch, CA
Exceeded the action level in the past
Latest 90th-percentile lead: 7.2 ppb (monitoring period 2026-2026). The federal action level is 15 ppb today and drops to 10 ppb in Nov 2027; EPA's health goal is 0. The latest result is under the action level, but this system has gone over 15 ppb before. Lead comes from pipes, not the source water, so a home with a lead service line can still be exposed. Test your own tap.
Camp Jones Gulch at a glance
Camp Jones Gulch serves about 44 people through 65 service connections, which makes it a very small system under EPA's size classes. It is privately owned and draws groundwater, in San Mateo County, California. EPA system ID: CA4100538; phone on file: 650-747-1208. They can tell you what your service line is made of and whether they pay to replace it.
Lead results over time
That is down 18.4 ppb from 25.6 ppb in the period ending 2025. The highest 90th-percentile result EPA holds for Camp Jones Gulch is 25.6 ppb across 9 monitoring periods, 2 of them over the 15 ppb action level.
| Period ending | 90th-percentile lead |
|---|---|
| 2026 | 7.2 ppb |
| 2025 | 25.6 ppb over 15 |
| 2025 | 25.6 ppb over 15 |
| 2024 | 0.39 ppb |
| 2022 | 0.39 ppb |
| 2021 | 1 ppb |
| 2018 | 2 ppb |
| 2017 | 5.5 ppb |
| 2016 | 0 (not detected) |
How Camp Jones Gulch compares
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. Camp Jones Gulch's 7.2 ppb sits at the 95th percentile in California and the 95th nationally (higher means more lead).
Neighbouring systems
35 other systems share San Mateo County; 1 of them has a higher latest lead result than Camp Jones Gulch. If you are unsure which one supplies your house, the name on your water bill decides it.
| System | People | Latest lead |
|---|---|---|
| California Water Service - San Mateo | 103,536 | 4.4 ppb |
| City Of Daly City | 102,593 | 0 (not detected) |
| City Of Redwood City | 90,043 | 0 (not detected) |
| California Water Service-S San Francisco | 62,609 | 4.1 ppb |
| California Water Service - Bear Gulch | 60,382 | 4 ppb |
| City Of San Bruno | 42,631 | 0 (not detected) |
| North Coast County Water Dist | 38,546 | 0 (not detected) |
| Estero Municipal Improvement District | 36,556 | 0 (not detected) |
| California Water Service - San Carlos | 34,801 | 5.8 ppb |
| City Of Burlingame | 32,453 | 6.3 ppb |
Next steps for La Honda, CA
Test your own tap with a certified lab first-draw sample; La Honda, CA may offer free or low-cost kits through the utility. If your own line is lead, replacing the private side runs about $1,200-$12,300 (EPA average about $4,700). Ask Camp Jones Gulch 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. More in what a past exceedance means today.