Hawaii: Oahu Flooding, Dam Failure Risk Persists; Thousands Evacuated, More Rain Expected

Oahu, Hawaii is grappling with historic flooding that has forced thousands to evacuate, particularly in towns north of Honolulu. The primary concern is the potential failure of the 120-year-old Wahiawa Dam (Lake Wilson), which is under constant monitoring. Emergency shelters are open, and the Hawaii National Guard has been activated. Roads have been washed out, homes damaged, and water rescues are underway. ## Latest Update More heavy rain is expected across Hawaii this weekend, increasing the risk of further flash floods and landslides on already saturated ground. The National Weather Service has issued flood watches, and emergency officials are urging residents to stay alert and avoid travel in flood-prone areas as the weather system moves through the region. The state is still assessing damage from the previous storm. ## Timeline * 2026-03-20: Heavy rains cause severe flooding on Oahu, prompting evacuation orders for thousands downstream of the Wahiawa dam. Officials warn of potential dam failure. * 2026-03-20: Gov. Josh Green declares a state of emergency and activates the Hawaii National Guard. * 2026-03-20: The Honolulu Department of Emergency Management warns that the Wahiawa Dam is at risk of overtopping or failure. * 2026-03-21: Over 5,500 people are told to evacuate as officials warn of potential dam failure. * 2026-03-21: The Hawaii Emergency Management Agency states the dam's integrity is under constant monitoring, but the risk of a catastrophic breach necessitates immediate relocation. * 2026-03-21: Emergency officials report over 4,000 residents evacuated due to the imminent threat of dam collapse. * 2026-03-21: Forecasters warn that heavy rain is expected to persist, increasing the risk of further flash floods and landslides. * 2026-03-21: Hawaii residents are preparing for another round of heavy rain this weekend, just days after devastating floods caused significant damage across the islands. ## What to Watch * Dam Integrity: Continue monitoring the status of the Wahiawa Dam and any updates from the Hawaii Emergency Management Agency. * Rainfall: Pay close attention to weather forecasts and heed warnings from the National Weather Service regarding further rainfall and potential flash flooding. * Infrastructure: Monitor reports of road closures, infrastructure damage, and disruptions to daily life across the islands.