Western Mwd (Id A - Rainbow), 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 Western Mwd (Id A - Rainbow)
Western Mwd (Id A - Rainbow) serves about 196 people through 41 service connections, which makes it a very small system under EPA's size classes. It is owned by a local government (city, town, county or district) and draws surface water, in Riverside County, California. EPA system ID: CA3310076; phone on file: 951-789-5155. Ask them for your address in their service line inventory - every system had to publish one by Oct 2024.
Every lead result on file
Against the period ending 2021 (0 ppb) the latest result is about the same. The highest 90th-percentile result EPA holds for Western Mwd (Id A - Rainbow) is 0 ppb across 3 monitoring periods, none of them over 15 ppb.
| Period ending | 90th-percentile lead |
|---|---|
| 2024 | 0 (not detected) |
| 2021 | 0 (not detected) |
| 2018 | 0 (not detected) |
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. Western Mwd (Id A - Rainbow)'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
92 other systems share Riverside County; 33 of them have a higher latest lead result than Western Mwd (Id A - Rainbow). If you are unsure which one supplies your house, the name on your water bill decides it.
| System | People | Latest lead |
|---|---|---|
| Eastern Municipal Wd | 659,923 | 2.8 ppb |
| Riverside, City Of | 302,776 | 1 ppb |
| Coachella Vwd: Cove Community | 270,000 | 0 (not detected) |
| Elsinore Valley Mwd | 169,455 | 1.3 ppb |
| Corona, City Of | 169,380 | 1.8 ppb |
| Rancho California Water District | 146,147 | 0 (not detected) |
| Jurupa Community Sd | 134,638 | 0 (not detected) |
| Indio Water Authority | 89,137 | 0 (not detected) |
| Western Mwd | 87,955 | 1.3 ppb |
| Desert Water Agency | 75,588 | 0 (not detected) |
Next steps for Riverside, CA
Look up your address in Western Mwd (Id A - Rainbow)'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 Western Mwd (Id A - Rainbow) 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. A zero today does not rule out a jump later - the rules are tightening in 2027.