Aging Wahiawa Dam Spurs Oahu Evacuations Amid Life‑Threatening Flooding and Homes Swept Away
Honolulu officials issued a 5:35 a.m. emergency evacuation for more than 4,000 people downstream of the 120‑year‑old Wahiawa Dam after warning it was "at risk of imminent failure" and reporting water actively running over the spillway amid 8–12 inches of overnight rain and National Weather Service warnings of "widespread life‑threatening flash flooding" across Haleiwa and Waialua. Mud-churned floodwaters — described as chest‑high in parts of north Oahu — have blared sirens, swept homes and vehicles off foundations, forced shelter relocations (about 185 people and 50 pets were bused from a flooded school shelter), prompted searches by firefighters and lifeguards on jet skis, and led to activation of the Hawaii National Guard as some residents remain isolated.
📌 Key Facts
- At 5:35 a.m. Friday Honolulu officials issued an emergency alert ordering downstream residents to evacuate because the 120‑year‑old Wahiawa Dam was "at risk of imminent failure"; the order covers more than 4,000 people and officials said water was actively running over the spillway.
- Emergency sirens blared along Oahu’s North Shore as muddy floodwaters pushed homes off foundations, swallowed vehicles and swept away some houses; the exact number of homes lost is not yet known.
- Firefighters and lifeguards on jet skis were searching floodwaters for stranded people amid reports of homes being swept away.
- Roughly 185 people and 50 pets sheltering at Waialua High and Intermediate School had to be evacuated and bused to another center after that shelter flooded.
- Officials reported 8–12 inches of rain overnight in parts of north Oahu on top of catastrophic flooding from last week; the National Weather Service warned of "widespread life‑threatening flash flooding," especially in Haleiwa and Waialua.
- Gov. Josh Green activated the Hawaii National Guard, described chest‑high floodwaters in parts of northern Oahu and called the situation a "very touch‑and‑go day," while a state senator said some residents are effectively isolated and unable to evacuate due to high water.
📊 Relevant Data
As of the end of Fiscal Year 2025, 94 out of 123 regulated dams in Hawaii are in poor or unsatisfactory condition, representing approximately 76% of the total.
Report to the Thirty-Third Legislature — Hawaii Department of Land and Natural Resources
115 out of 123 regulated dams in Hawaii are classified as high-hazard, meaning their failure could likely cause loss of human life or significant property damage.
Report to the Thirty-Third Legislature — Hawaii Department of Land and Natural Resources
The average age of regulated dams in Hawaii is 91 years, with many built before modern safety standards and not meeting current requirements for impounding water.
Report to the Thirty-Third Legislature — Hawaii Department of Land and Natural Resources
Climate change is contributing to more intense rainfall events in Hawaii, despite an overall decline in rainfall, increasing the frequency and severity of flooding.
Less & Heavy Rain - Climate Change Portal — State of Hawaii
Native Hawaiian communities in Hawaii are disproportionately affected by climate change hazards, including flooding, due to limited resources for recovery; Native Hawaiians make up about 10% of the state's population but face higher vulnerability.
Spotlights - Climate Change Portal — State of Hawaii
📰 Source Timeline (3)
Follow how coverage of this story developed over time
- Honolulu officials say emergency sirens blared along Oahu’s North Shore as muddy floodwaters pushed homes off their foundations, swallowed vehicles and swept away some houses, though the exact number is not yet known.
- Honolulu’s 5:35 a.m. evacuation order covers more than 4,000 people downstream of the 120‑year‑old Wahiawa Dam, with officials warning it is "at risk of imminent failure" and water is actively running over the spillway.
- Roughly 185 people and 50 pets sheltering at Waialua High and Intermediate School had to be relocated by bus after that shelter flooded, amid 8–12 inches of overnight rain and what NWS calls "widespread life‑threatening flash flooding" in Haleiwa and Waialua.
- Gov. Josh Green says the Hawaii National Guard has been activated and describes chest‑high floodwaters on parts of northern Oahu, calling it a "very touch‑and‑go day," while a state senator says some residents are effectively isolated and unable to evacuate due to high water.
- Honolulu officials issued a specific 5:35 a.m. emergency alert Friday telling residents downstream of Wahiawa Dam to evacuate because it was 'at risk of imminent failure.'
- Honolulu Department of Emergency Management spokesperson Molly Pierce said the evacuation order covers more than 4,000 people and confirmed that 'water is actively running over the spillway right now.'
- City spokesperson Ian Scheuring said firefighters and lifeguards on jet skis are searching floodwaters for stranded people and that there are reports of homes being swept away, though the total is not yet known.
- Roughly 185 people and 50 pets sheltering at Waialua High and Intermediate School had to be evacuated and bussed to another center because that shelter itself flooded.
- Officials reported 8 to 12 inches of rain overnight in parts of north Oahu, on top of catastrophic flooding from last week’s storm, with the National Weather Service warning of 'widespread life-threatening flash flooding' particularly in Haleiwa and Waialua.