R.S. Mutual Water Company, CA
Exceeded the action level in the past
Latest 90th-percentile lead: 0.6 ppb (monitoring period 2024-2024). The federal action level is 15 ppb today and drops to 10 ppb in Nov 2027; EPA's health goal is 0. The latest 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.
Who runs the water here
R.S. Mutual Water Company serves about 35 people through 22 service connections, which makes it a very small system under EPA's size classes. It is privately owned and draws groundwater, in Kern County, California. EPA system ID: CA1500458; phone on file: 760-478-8385. They can tell you what your service line is made of and whether they pay to replace it.
R.S. Mutual Water Company's lead record
Against the period ending 2023 (0.5 ppb) the latest result is about the same. The highest 90th-percentile result EPA holds for R.S. Mutual Water Company is 50 ppb across 6 monitoring periods, 1 of them over the 15 ppb action level.
| Period ending | 90th-percentile lead |
|---|---|
| 2024 | 0.6 ppb |
| 2023 | 0.5 ppb |
| 2022 | 0.5 ppb |
| 2022 | 0 (not detected) |
| 2021 | 50 ppb over 15 |
| 2018 | 0.7 ppb |
How R.S. Mutual Water Company 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. R.S. Mutual Water Company's 0.6 ppb sits at the 65th percentile in California and the 44th nationally (higher means more lead).
Other water systems in Kern County
165 other systems share Kern County; 70 of them have a higher latest lead result than R.S. Mutual Water Company. 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 |
What to do in your house
Test your own tap with a certified lab first-draw sample; Wofford Heights, 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 R.S. Mutual Water Company 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. More in what a past exceedance means today.