Cws-Split Mountain Water System, CA
Exceeded the action level in the past
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 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.
About Cws-Split Mountain Water System
Cws-Split Mountain Water System serves about 203 people through 159 service connections, which makes it a very small system under EPA's size classes. It is privately owned and draws surface water, in Kern County, California. EPA system ID: CA1500407; phone on file: 408-367-8593. They can tell you what your service line is made of and whether they pay to replace it.
Every lead result on file
That is down 3.1 ppb from 3.1 ppb in the period ending 2023. The highest 90th-percentile result EPA holds for Cws-Split Mountain Water System is 17.1 ppb across 8 monitoring periods, 1 of them over the 15 ppb action level.
| Period ending | 90th-percentile lead |
|---|---|
| 2026 | 0 (not detected) |
| 2023 | 3.1 ppb |
| 2022 | 3.6 ppb |
| 2021 | 6.3 ppb |
| 2020 | 0 (not detected) |
| 2019 | 8.1 ppb |
| 2019 | 8.23 ppb |
| 2018 | 17.1 ppb over 15 |
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. Cws-Split Mountain Water System's reported as 0 (not detected) sits at the 28th percentile in California and the 15th nationally (higher means more lead). Systems reporting 0 tie at the bottom, so the rank mostly reflects size among them.
Other water systems in Kern County
165 other systems share Kern County; 75 of them have a higher latest lead result than Cws-Split Mountain Water System. If you are unsure which one supplies your house, the name on your water bill decides it.
| System | People | Latest lead |
|---|---|---|
| Cws - Bakersfield | 268,129 | 2.8 ppb |
| Bakersfield, City Of | 171,108 | 1.3 ppb |
| Delano, City Of | 51,428 | 0 (not detected) |
| Oildale Mwc | 45,315 | 0 (not detected) |
| Indian Wells Valley W.D. | 41,474 | 0 (not detected) |
| Tejon Castac Wd - I5 & Laval Rd | 38,125 | 0 (not detected) |
| Antelope Valley E Kern Wtr Agy-Rosamond | 37,634 | - |
| Vaughn Wc Inc | 37,189 | 0 (not detected) |
| East Niles Csd | 32,517 | 1.4 ppb |
| Cws - North Garden | 27,634 | 4.2 ppb |
Next steps for San Jose, CA
Test your own tap with a certified lab first-draw sample; San Jose, 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 Cws-Split Mountain Water System 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. Why sampled homes are the worst-case ones is in the guide to reading the number. Why an old exceedance still matters: over the limit before, under it now.