KONA LOW STORM RECOVERY
BWS Water Sampling & Testing on the North Shore
Following the Kona low storm flooding along Oʻahu's North Shore on March 21, 2026, the BWS issued a boil water notice for its customers from& Mokulēʻia to Turtle Bay. This notice remained in effect until the BWS could conduct damage assessments along its interconnected water system serving the area and until the water could be tested for potential bacteriological contamination. The notice was lifted for Pūpūkea Road to Turtle Bay on March 24, 2026, and then from Pūpūkea Road to Waialua at 68-431 Farrington Highway on March 25, 2026.
BWS crews entered the area to conduct damage assessments as soon as the North Shore evacuation notice was lifted. No damage was found along the BWS's water system infrastructure for the North Shore. Since there was no way for chemicals such as lead or pesticides that could have been spread by the Kona low storm flooding to enter the BWS system, testing to clear the boil water notice focused on potential bacteriological contamination.
Water Sampling & Testing
Samples were taken along the BWS water system at our reservoirs, along transmission mains, and at representative points in the system including the furthest parts of the water system and schools. This provided the BWS with a look at the water quality for its North Shore system following the Kona low storm flooding. Samples were sent to the BWS labs for testing. It takes about a day for the results to come back.
BWS tested for total coliform and E. Coli, which are indicator organisms that test for fecal contamination. The presence of these organisms helps us to determine if the water had been contaminated. Microbiological testing results are reported as either absent or present.
BWS also tested for chlorine, which when present, kills/prevents the growth of bacteria. Having a free chlorine residual in the water indicates to us that the water is protected and safe. Free chlorine (CL2) helps to deactivate bacteria and is measured in milligrams per liter (mg/L or ppm).
Waialee – Pūpūkea Test Results
| Bacterial test results | ||||
|---|---|---|---|---|
| Location | Address | CL2* | Total Coliform | E. Coli |
| Sunset Beach Church of Christ | 59-578 Kamehameha Hwy | 0.24 | Absent | Absent |
| Ehukai Beach Park | 59-337 Ke Nui Rd | 0.25 | Absent | Absent |
| Sunset Beach Elementary School | 59-404 Kamehameha Hwy | 0.21 | Absent | Absent |
| Texaco Service Station | 59-186 Kamehameha Hwy | 0.21 | Absent | Absent |
| Sunset Beach Support Park | 59-104 Kamehameha Hwy | 0.22 | Absent | Absent |
| 58-123 Wehiwa Pl | 58-123 Wehiwa Pl | 0.21 | Absent | Absent |
| 58-114 Mamao St | 58-114 Mamao St | 0.20 | Absent | Absent |
| Lei Lei's | 57-049 Kuilima Dr | 0.24 | Absent | Absent |
| Kawela Reservoir | Kamehameha Hwy | 0.21 | Absent | Absent |
| 56-1101 Kamehameha Hwy | 56-1101 Kamehameha Hwy | 0.23 | Absent | Absent |
| Haleiwa Foodland | 59-720 Kamehameha Hwy | 0.20 | Absent | Absent |
| Pupukea Booster #2 | Pupukea Rd | 0.34 | Absent | Absent |
| Pupukea 170 Reservoir | Pupukea Rd | 0.32 | Absent | Absent |
| 59-415 Alapio Rd | 59-415 Alapio Rd | 0.23 | Absent | Absent |
| Pupukea 600 Reservoir | Pupukea Rd | 0.26 | Absent | Absent |
| 59-632 Maulukua Pl | 59-632 Maulukua Pl | 0.08 | Absent | Absent |
| Pupukea 892 Reservoir | Pupukea Rd | 0.17 | Absent | Absent |
| * CL2 = Free Chlorine Residual (mg/L or ppm) | ||||
Haleiwa to Waialua Test Results
| Bacterial test results | ||||
|---|---|---|---|---|
| Location | Address | CL2* | Total Coliform | E. Coli |
| Waialua Reservoir | Kamehameha Hwy | 0.38 | Absent | Absent |
| Haleiwa 7 Eleven | 66-610 Kamehameha Hwy | 0.36 | Absent | Absent |
| Hydrant C01965 | ~66-288 Kamehameha Hwy | 0.70 | Absent | Absent |
| Waialua Elementary School | 59-443 Pupukea Rd | 0.44 | Absent | Absent |
| Waialua Rec Center | 67-180 Goodale Ave | 0.33 | Absent | Absent |
| Waialua Int and High School | 67-160 Farrington Hwy | 0.39 | Absent | Absent |
| Aweoweo Beach Park | 68-197 Au St | 0.32 | Absent | Absent |
| Waimea Bay Beach Park | 61-031 Kamehameha Hwy | 0.23 | Absent | Absent |
| Haleiwa Community and Surf Center | 66-167 Haleiwa Rd | 0.26 | Absent | Absent |
| Hydrant C01415 | ~68-781 Crozier Dr | 0.79 | Absent | Absent |
| Hydrant C02266 | ~68-431 Farrington Hwy | 0.22 | Absent | Absent |
| * CL2 = Free Chlorine Residual (mg/L or ppm) | ||||
All the samples were reported as absent of bacteria, indicating to BWS that the water in the system was safe for consumption.
Had bacteria had been indicated in the samples, BWS would have kept the boil water notice in place and conducted more extensive testing in the affected area(s).
BWS’s groundwater sources are not affected by surface water – rivers, lakes, streams or even flooding. Oʻahu's water is filtered through porous volcanic rock for as long as 25 years before entering the underground aquifers and being pumped into the BWS water system. Also, due to the presence of legacy pesticides, water pumped from Waialua Wells is filtered through Granular Activated Carbon (GAC) before it enters the storage and distribution system serving the North Shore.
If you have further questions about the boil water notice testing, please send an email to contactus@hbws.org.
Updated: 03/27/2026