Cascade Estates, CA
Lead detected, under the action levels
Latest 90th-percentile lead: 3.67 ppb (monitoring period 2024-2026). 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.
Who runs the water here
Cascade Estates serves about 316 people through 113 service connections, which makes it a very small system under EPA's size classes. It is privately owned and draws groundwater, in Tuolumne County, California. EPA system ID: CA5500104; phone on file: 415-927-9013. They can tell you what your service line is made of and whether they pay to replace it.
Cascade Estates's lead record
That is down 3.89 ppb from 7.56 ppb in the period ending 2023. The highest 90th-percentile result EPA holds for Cascade Estates is 7.56 ppb across 4 monitoring periods, none of them over 15 ppb.
| Period ending | 90th-percentile lead |
|---|---|
| 2026 | 3.67 ppb |
| 2023 | 7.56 ppb |
| 2020 | 1.16 ppb |
| 2017 | 0 (not detected) |
How Cascade Estates 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. Cascade Estates's 3.67 ppb sits at the 88th percentile in California and the 86th nationally (higher means more lead).
Neighbouring systems
48 other systems share Tuolumne County; 10 of them have a higher latest lead result than Cascade Estates. If you are unsure which one supplies your house, the name on your water bill decides it.
| System | People | Latest lead |
|---|---|---|
| Tud - Upper Basin Water System | 13,331 | 0 (not detected) |
| Tud - Sonora/Jamestown Water System | 11,113 | 0 (not detected) |
| Tud - Columbia Water System | 5,482 | 5.4 ppb |
| Cdcr - Sierra Conservation Center | 3,571 | 0 (not detected) |
| Groveland Community Serv Dist | 3,400 | 0 (not detected) |
| Twain Harte Community Services District | 2,378 | 0 (not detected) |
| Tud - Tuolumne Water System | 1,798 | 0 (not detected) |
| Tud - Ponderosa | 1,781 | 0 (not detected) |
| Cold Springs Water Co | 1,771 | 2.8 ppb |
| Lake Don Pedro Csd | 1,700 | 0 (not detected) |
What to do in your house
Test your own tap with a certified lab first-draw sample; Larkspur, 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 Cascade Estates 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. Why sampled homes are the worst-case ones is in the guide to reading the number. Size matters more than most people expect: small vs large water systems.