Hawaii Flooding: Evacuations Ordered as Wahiawa Dam Faces Imminent Failure

Severe rainfall has triggered widespread flooding across Oahu’s North Shore, Hawaii, prompting evacuation orders for over 5,500 residents and raising concerns about the potential failure of the 120-year-old Wahiawa Dam. The flooding, which began on Friday, March 20, 2026, has inundated streets, damaged homes, and led to over 230 rescues.

Flash Flood Emergency and Evacuation Orders

Honolulu officials issued a “LEAVE NOW” evacuation order at 5:35 a.m. On Friday for Waialua and Haleiwa, citing “extremely dangerous flooding” and the high-risk situation at the Wahiawa Dam [CBS News]. Residents downstream of the dam were urged to evacuate immediately as authorities warned of potential life-threatening flooding [Times Now].

Widespread Damage and Rescue Efforts

Muddy floodwaters have engulfed streets and vehicles, causing significant damage to homes, and infrastructure. Honolulu Mayor Rick Blangiardi reported that dozens, if not hundreds, of homes have been damaged, with a full assessment of the destruction still underway [CBS News]. Over 233 people have been rescued so far, and the flooding is estimated to have caused over $1 billion in damage [CBS News].

Rescue crews have been working tirelessly by air and water to reach stranded individuals. Governor Josh Green reported that dozens of people were rescued within a single hour, including two with serious injuries, and ten who were treated for hypothermia [CBS News]. The National Guard and Honolulu Fire Department airlifted 72 children and adults from a spring break youth camp at Our Lady of Kea’au retreat on Oahu’s west coast [CBS News].

Wahiawa Dam Concerns

The aging Wahiawa Dam is a major concern for residents, particularly during periods of heavy rainfall. Kathleen Pahinui, a Waialua resident, expressed her worry about the dam’s condition every time it rains [AP News]. As of 9:00 AM HST on Friday, authorities stated that the Wahiawa Dam had not failed but was at imminent risk of failure, potentially leading to catastrophic flooding [Times Now].

Impact and Ongoing Risks

The flooding has impacted areas along the Kaukonahua Stream and nearby waterways, including the North Fork of Kaukonahua Stream, Poamoho Stream, Kiikii Stream, Mohiakea Gulch, the Anahulu River, and Helemano/Opaeula Stream [Times Now]. Officials are urging residents to stay off the roads, avoid floodwaters, and check on their neighbors [AP News].

An evacuation advisory was also issued for some Lahaina neighborhoods on Maui due to nearby retention basins nearing capacity, an area still recovering from the devastating 2023 wildfires [CBS News].

Looking Ahead

More rain is expected on Saturday, continuing the risk of flooding and potential dam failure. Residents are advised to stay informed and follow the guidance of emergency officials. The intensity and frequency of heavy rains in Hawaii have increased in recent years, a trend experts attribute to human-caused global warming [AP News].