Nas North Island & Nab Coronado, CA
Lead detected, under the action levels
Latest 90th-percentile lead: 1.27 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
Nas North Island & Nab Coronado serves about 421 people through 2,218 service connections, which makes it a very small system under EPA's size classes. It is federally owned and draws surface water, in San Diego County, California. EPA system ID: CA3710750; phone on file: 619-545-1130. Ask them for your address in their service line inventory - every system had to publish one by Oct 2024.
Lead results over time
That is up 1.27 ppb from 0 ppb in the period ending 2023. The highest 90th-percentile result EPA holds for Nas North Island & Nab Coronado is 1.27 ppb across 5 monitoring periods, none of them over 15 ppb.
| Period ending | 90th-percentile lead |
|---|---|
| 2026 | 1.27 ppb |
| 2023 | 0 (not detected) |
| 2020 | 0 (not detected) |
| 2017 | 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. Nas North Island & Nab Coronado's 1.27 ppb sits at the 73rd percentile in California and the 60th nationally (higher means more lead).
Other water systems in San Diego County
80 other systems share San Diego County; 18 of them have a higher latest lead result than Nas North Island & Nab Coronado. If you are unsure which one supplies your house, the name on your water bill decides it.
| System | People | Latest lead |
|---|---|---|
| San Diego, City Of | 1,408,937 | 0 (not detected) |
| Helix Water District | 277,918 | 0 (not detected) |
| Otay Water District | 242,155 | 0 (not detected) |
| Sweetwater Authority | 184,915 | 0 (not detected) |
| Oceanside, City Of | 174,340 | 0 (not detected) |
| Escondido, City Of | 137,044 | 1.1 ppb |
| Vista Irrigation District | 134,501 | 0 (not detected) |
| Vallecitos Wd | 114,700 | 0 (not detected) |
| Cal-Am Water Coronado | 106,000 | 2 ppb |
| Carlsbad Mwd | 96,371 | 0 (not detected) |
Next steps for San Diego, CA
Test your own tap with a certified lab first-draw sample; San Diego, 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 Nas North Island & Nab Coronado 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. The action level is dropping - the 10 ppb rule from 2027.