Waiahole, HI
Lead reported as not detected
Latest 90th-percentile lead: reported as 0 (not detected) (monitoring period 2019-2021). The federal action level is 15 ppb today and drops to 10 ppb in Nov 2027; EPA's health goal is 0. The latest 90th-percentile result was reported as 0 (not detected at the lab's limit). That says the sampled homes were low, not that your home has no lead service line. Check your utility's service line inventory for your address.
Waiahole at a glance
Waiahole serves about 300 people through 112 service connections, which makes it a very small system under EPA's size classes. It is owned by the state and draws groundwater, in Honolulu County, Hawaii. EPA system ID: HI0000368. Ask the utility on your bill for your address in their service line inventory.
Waiahole's lead record
The highest 90th-percentile result EPA holds for Waiahole is 0 ppb across 1 monitoring period, none of them over 15 ppb.
| Period ending | 90th-percentile lead |
|---|---|
| 2021 | 0 (not detected) |
How Waiahole compares
Of the 112 Hawaii systems with a lead result, the median latest reading is 0 ppb; 0 are over 15 ppb right now and 1 have gone over at some point. Waiahole's reported as 0 (not detected) sits at the 27th percentile in Hawaii and the 18th nationally (higher means more lead). Systems reporting 0 tie at the bottom, so the rank mostly reflects size among them.
Other water systems in Honolulu County
28 other systems share Honolulu County; 0 of them have a higher latest lead result than Waiahole. If you are unsure which one supplies your house, the name on your water bill decides it.
| System | People | Latest lead |
|---|---|---|
| Hnl-Windward-Pearl Harbor | 631,389 | 0 (not detected) |
| Waipahu-Ewa-Waianae | 217,479 | 0 (not detected) |
| Joint Base Pearl Harbor-Hickam | 65,230 | 0 (not detected) |
| Mililani | 50,573 | 0 (not detected) |
| Schofield Barracks | 37,920 | 0 (not detected) |
| Wahiawa | 23,348 | 0 (not detected) |
| Marine Corps Base Hawaii | 16,300 | 0 (not detected) |
| Waipio Heights | 11,516 | 0 (not detected) |
| Waialua-Haleiwa | 9,996 | 0 (not detected) |
| Fort Shafter | 7,067 | 0 (not detected) |
Your move
Look up your address in Waiahole's service line inventory. If it says lead, galvanized or unknown, test your tap. If your own line is lead, replacing the private side runs about $1,200-$12,300 (EPA average about $4,700). Ask Waiahole 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. Small systems behave differently: why small systems go over more often.