Rancho Borromeo Mwc, CA
Lead detected, under the action levels
Latest 90th-percentile lead: 2.8 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.
Who runs the water here
Rancho Borromeo Mwc serves about 100 people through 36 service connections, which makes it a very small system under EPA's size classes. It is privately owned and draws groundwater, in Monterey County, California. EPA system ID: CA2700709; phone on file: 831-663-6071. Ask them for your address in their service line inventory - every system had to publish one by Oct 2024.
Rancho Borromeo Mwc's lead record
That is up 2.2 ppb from 0.6 ppb in the period ending 2024. The highest 90th-percentile result EPA holds for Rancho Borromeo Mwc is 2.8 ppb across 9 monitoring periods, none of them over 15 ppb.
| Period ending | 90th-percentile lead |
|---|---|
| 2025 | 2.8 ppb |
| 2024 | 0.6 ppb |
| 2023 | 0 (not detected) |
| 2022 | 0 (not detected) |
| 2021 | 0 (not detected) |
| 2020 | 0.3 ppb |
| 2018 | 0 (not detected) |
| 2016 | 0 (not detected) |
| 2016 | 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. Rancho Borromeo Mwc's 2.8 ppb sits at the 84th percentile in California and the 80th nationally (higher means more lead).
Neighbouring systems
155 other systems share Monterey County; 41 of them have a higher latest lead result than Rancho Borromeo Mwc. If you are unsure which one supplies your house, the name on your water bill decides it.
| System | People | Latest lead |
|---|---|---|
| Cal Am Water Company - Monterey | 128,928 | 1 ppb |
| Cwsc Salinas | 114,286 | 1.2 ppb |
| Alco Water Service | 56,253 | 0 (not detected) |
| Marina Coast Water District | 38,918 | 0 (not detected) |
| Soledad, City Of | 19,732 | 0 (not detected) |
| Greenfield, City Of | 18,967 | 0 (not detected) |
| Cwsc King City | 14,046 | 0 (not detected) |
| Gonzales, City Of | 8,333 | 0 (not detected) |
| Cwsc Salinas Hills | 7,733 | 0.9 ppb |
| Castroville Community Services District | 7,515 | 0 (not detected) |
What to do in your house
Test your own tap with a certified lab first-draw sample; Salinas, 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 Rancho Borromeo Mwc whether it covers that cost before hiring anyone - many utilities now do. Its latest copper 90th percentile is 1493 ppb (copper action level 1,300 ppb).
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.