Joshua Basin Water District, CA
Lead detected, under the action levels
Latest 90th-percentile lead: 9.6 ppb (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. 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.
Joshua Basin Water District at a glance
Joshua Basin Water District serves about 6,489 people through 5,574 service connections, which makes it a medium-sized system under EPA's size classes. It is owned by a local government (city, town, county or district) and draws groundwater, in San Bernardino County, California. EPA system ID: CA3610025; phone on file: 760-366-8438. They can tell you what your service line is made of and whether they pay to replace it.
Lead results over time
That is up 9.6 ppb from 0 ppb in the period ending 2022. The highest 90th-percentile result EPA holds for Joshua Basin Water District is 9.6 ppb across 4 monitoring periods, none of them over 15 ppb.
| Period ending | 90th-percentile lead |
|---|---|
| 2025 | 9.6 ppb |
| 2022 | 0 (not detected) |
| 2019 | 0 (not detected) |
| 2016 | 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. Joshua Basin Water District's 9.6 ppb sits at the 97th percentile in California and the 97th nationally (higher means more lead).
Other water systems in San Bernardino County
146 other systems share San Bernardino County; 5 of them have a higher latest lead result than Joshua Basin Water District. 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 |
Next steps for Joshua Tree, CA
Test your own tap with a certified lab first-draw sample; Joshua Tree, 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 Joshua Basin Water District 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. Systems that went over once often dip back under; here is what that means.