Riverside Highland Water Company, CA
Lead detected, under the action levels
Latest 90th-percentile lead: 1.5 ppb (monitoring period 2025-2025). The federal action level is 15 ppb today and drops to 10 ppb in Nov 2027; EPA's health goal is 0. Lead was measured in sampled homes but the 90th percentile is under both action levels. EPA's health goal for lead is zero, so test your own tap if your home was built before 1986 or anyone in it is pregnant or a young child.
About Riverside Highland Water Company
Riverside Highland Water Company serves about 19,053 people through 6,748 service connections, which makes it a large system under EPA's size classes. It is privately owned and draws groundwater, in San Bernardino County, California. EPA system ID: CA3610057; phone on file: 909-825-4128. Ask them for your address in their service line inventory - every system had to publish one by Oct 2024.
Riverside Highland Water Company's lead record
That is up 1.5 ppb from 0 ppb in the period ending 2021. The highest 90th-percentile result EPA holds for Riverside Highland Water Company is 1.5 ppb across 3 monitoring periods, none of them over 15 ppb.
| Period ending | 90th-percentile lead |
|---|---|
| 2025 | 1.5 ppb |
| 2021 | 0 (not detected) |
| 2018 | 0 (not detected) |
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. Riverside Highland Water Company's 1.5 ppb sits at the 75th percentile in California and the 64th nationally (higher means more lead).
Nearby utilities
146 other systems share San Bernardino County; 27 of them have a higher latest lead result than Riverside Highland Water Company. If you are unsure which one supplies your house, the name on your water bill decides it.
| System | People | Latest lead |
|---|---|---|
| San Gabriel Valley Wc - Fontana | 228,270 | 0 (not detected) |
| San Bernardino City | 214,665 | 0 (not detected) |
| Cucamonga Valley Water District | 213,375 | 0 (not detected) |
| Ontario Municipal Utilities Company | 185,010 | 0.6 ppb |
| Victorville Water District | 140,721 | 0 (not detected) |
| San Bernardino Valley Wd | 109,608 | - |
| East Valley Water District | 108,600 | 0 (not detected) |
| Hesperia Wd | 101,836 | 0 (not detected) |
| West Valley Water District | 96,123 | 0 (not detected) |
| Chino, City Of | 90,187 | 1 ppb |
Your move
Test your own tap with a certified lab first-draw sample; Grand Terrace, 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 Riverside Highland 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. Size matters more than most people expect: small vs large water systems.