Sterling Mutual Water Company, CA
Lead reported as not detected
Latest 90th-percentile lead: reported as 0 (not detected) (monitoring period 2023-2025). 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.
Who runs the water here
Sterling Mutual Water Company serves about 198 people through 198 service connections, which makes it a very small system under EPA's size classes. It is privately owned and draws groundwater, in Los Angeles County, California. EPA system ID: CA1910158; phone on file: 626-350-9314. 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 2019 (1 ppb) the latest result is about the same. The highest 90th-percentile result EPA holds for Sterling Mutual Water Company is 1.9 ppb across 3 monitoring periods, none of them over 15 ppb.
| Period ending | 90th-percentile lead |
|---|---|
| 2025 | 0 (not detected) |
| 2019 | 1 ppb |
| 2016 | 1.9 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. Sterling Mutual Water Company's reported as 0 (not detected) sits at the 27th 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.
Neighbouring systems
197 other systems share Los Angeles County; 42 of them have a higher latest lead result than Sterling Mutual Water Company. If you are unsure which one supplies your house, the name on your water bill decides it.
| System | People | Latest lead |
|---|---|---|
| Los Angeles-City, Dept. Of Water & Power | 3,875,566 | 3.9 ppb |
| Long Beach Utilities Department | 466,772 | 0.97 ppb |
| Santa Clarita Valley Water Agency | 292,014 | 0 (not detected) |
| Gswc - Southwest | 277,740 | 1.7 ppb |
| San Gabriel Valley Water Co.-El Monte | 240,000 | 0 (not detected) |
| Los Angeles Cwwd 40 Reg 4 & 34 Lancaster | 208,129 | 1.8 ppb |
| Glendale-City, Water Dept. | 192,212 | 5.3 ppb |
| Suburban Water Systems-San Jose | 170,523 | 0 (not detected) |
| Pasadena Water And Power | 165,448 | 1.9 ppb |
| Pomona - City, Water Dept. | 151,713 | 2.1 ppb |
Next steps for El Monte, CA
Look up your address in Sterling Mutual Water Company'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 Sterling 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. The lead result guide covers how utilities pick the homes they sample. Small systems behave differently: why small systems go over more often.