Officials Warn of Potential Dam Collapse Amid Severe Flooding on Oahu
Authorities have issued evacuation orders for thousands of residents following severe flash floods and the imminent threat of a dam failure in northern Oahu, Hawaii. The Wahiawā dam is reported to be at risk of collapsing, raising concerns about rising floodwaters trapping residents downstream.
Videos circulated on social media early Friday showed streets inundated with fast-moving floodwaters and vehicles being engulfed by muddy water. The flooding intensified overnight as heavy rains continued to impact the region.
On Friday morning, the Wahiawā dam was observed to have water flowing over its spillway at a rate of 1,500 gallons per second. Oahu Emergency Management issued a warning stating the dam
“may collapse or breach at any time.”In response, Honolulu officials sent emergency messages urging residents living downstream of the dam to evacuate immediately.
Evacuation Orders and Emergency Response
Emergency sirens sounded along Oahu’s North Shore, an area that also experienced flooding damage to homes. At 5:35 a.m. on Friday, Honolulu officials issued a
“LEAVE NOW”evacuation order for the communities of Waialua and Haleiwa, citing
“Extremely dangerous flooding and Wahiawa dam is high.”
Many roads were already flooded, complicating evacuation efforts. A shelter located at Waialua High School lost power early Friday and was forced to evacuate its occupants. Approximately 185 people and 50 pets had sought refuge there but were being transported to an alternate evacuation center.
State Representative Amy Perruso, representing the North Shore, informed Honolulu Civil Beat that emergency services were struggling to reach residents due to submerged vehicles and flooded roads. She stated,
“There’s no exit possibility for a lot of folks right now.”
The Honolulu emergency department advised those trapped by floodwaters to seek the highest level of their homes and to avoid attics without roof access, stating early Friday,
“If you are trapped, go to the highest level. Stay out of attics without a way to the roof.”
Ongoing Storm and Flooding Conditions
The current flooding follows a previous storm last week that produced heavy rainfall across Hawaii, causing widespread damage including washed-out roads and destroyed homes. Despite the initial storm subsiding, a subsequent, less intense storm was forecast to bring additional rain through the weekend.
Governor Josh Green announced via social media that the Hawaii National Guard had been activated to assist with flood response efforts. He described the situation as
“very severe right now, particularly on the northern part of Oahu,”with floodwaters reaching chest height. He added,
“It’s going to be a very touch-and-go day.”
The flash flooding occurred just days after a multi-day storm deposited over a foot of rain in various parts of Hawaii. The National Weather Service placed most of the state under a flood watch, with northern Oahu specifically under a flash flood warning due to
“widespread life-threatening flash flooding,”particularly in the communities of Haleiwa and Waialua.
Evacuations and Community Impact
Ian Scheuring, spokesperson for Honolulu, confirmed that the Waialua High and Intermediate School shelter was being evacuated due to flooding concerns. Residents and pets were being relocated to safer facilities.
Waialua resident Kathleen Pahinui, preparing to evacuate to a friend’s home on higher ground, expressed ongoing concerns about the aging dam. In a phone interview with the Associated Press, she said,
“Just pray for us. We understand there’s more rain coming.”
Molly Pierce, spokesperson for the Honolulu Department of Emergency Management, estimated that the evacuation order affected more than 4,000 people, though the actual number could be higher. She noted that officials had issued a warning for the dam during last week’s heavy rains, but water levels had receded as the rain diminished. However, she emphasized,
“The water is actively running over the spillway right now.”
Background on Hawaii’s Dam Infrastructure
Hawaii regulates 132 dams statewide, most originally constructed as part of irrigation systems for the sugar cane industry, according to a 2019 infrastructure report by the American Society of Civil Engineers.
Historical context underscores the risks associated with dam failures in the state. In 2006, the collapse of the Ka Loko dam on Kauai resulted in seven fatalities when floodwaters rushed downhill.
