After two powerfulstorms struck Hawaiiover the past week, officials are warning that one of the largest dams on the island of Oahu is at risk of imminent failure.
Water was flowing over the top of the Wahiawa dam on Thursday morning local time. Officials issued evacuation notices for two towns, Waialua and Haleiwa, which were already dealing with local flooding but could get inundated if the dam fails.
"We've got a little over 4,000 people directly within the dam evacuation area," said Molly Pierce, a spokesperson for the Oahu Department of Emergency Management.
Hawaii Gov. Josh Green urged residents to follow the guidance from emergency officials.
"If you are in these areas, please evacuate now," he said in a statement.
The 660-foot-long earthen dam can hold up to 9,200 acre-feet of water (roughly 4,600 Olympic sized swimming pools). It is equipped with a 183-foot wide spillway.
"It could fail," Pierce said of the dam. "At this point, we don't have a good way of determining if it is a risk of imminent failure or just overtopping."
The dam was built in 1906 and is owned by the Dole Food Company. It holds back irrigation water, forming a reservoir named Lake Wilson, but was considered in "poor" condition at the time of a 2020 inspection, according to Hawaii's Department of Land and Natural Resources. The department said in an email on Friday that its flood risk management team was not available for interviews because they were handling imminent public safety issues.
William Goldfield, director of corporate communications for the Dole Food Company, said in an email that the company "is working closely with authorities and continues to monitor the reservoirs including Lake Wilson," with public safety as the top priority.
"The dam continues to operate as designed with no indications of damage," he continued.
The state of Hawaii had been in talks to acquire the dam from Dole for several years. State records show that dam safety officials had been tracking the structure's deficiencies for more than a decade.
"In a major storm event, the undersized spillway may not be able to pass the Probable Flood, which could potentially result in a failure from water overtopping the dam embankment," Carty Chang, the state's chief engineer, wrote ina 2024 letter.
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The letter says about 2,500 people would be at risk if the dam failed.
Oahu is expected to remain under flood watch through Sunday, said Stephen Parker, an NWS meteorologist based in Honolulu.
"We've had 8 to 12 inches of rain across northern Oahu over the last 12 to 16 hours," he said. "It's hard to find a spot where there hasn't been some flooding."
Nate Serota, a spokesperson for the Honolulu Department of Parks and Recreation, said there have been multiple reports of flooding on roadways in Waialua and Haleiwa, including a few cases in which officials sent high clearance vehicles to rescue people.
Footage of Oahu shared on social media showed cars submerged in water and neighbors wading through flooded streets. A home in Mokuleia, on the island's north shore, was washed away overnight.
This is the second week of intense rainfall in the Hawaiian islands.More than 5 feet of rain fell in some parts of Maui from March 10 to 16, during what's known as a kona storm, a weather pattern in which winds come from the south, drawing heavy precipitation to leeward areas of the islands that are usually more sheltered from heavy rain.
"The ground was still very wet from last weekend's system. Not much of this was absorbed," Parker said on Friday.
The current storm, he added, is expected to deliver one or two more pulses of rain. Although streamflow gauges suggested that water levels werefalling at Wahiawa dam by Friday afternoon, Parker said, the dam is not out of the woods.
"If we were to get a big dose tonight, it would reinvigorate that threat," he said.
Green closed Hawaii state offices and departments on Friday, with the exception of emergency management, and sent employees home.
"With catastrophic flash flooding already impacting parts of Oahu, including evacuation orders on the North Shore and the potential for dam-related impacts, we are taking this situation extremely seriously," he said. "Closing state offices will allow families to focus on getting to safety."
The extreme rain coincides with a period of wild weather across the United States. California and the desert Southwest have been baking in a severeheat wave this week. Lake Martinez in Arizona hit 110 degrees Fahrenheit on Thursday, the highest March temperature in U.S. recorded history. Earlier this week, heavy snow fell in the Midwest, and Nebraska experienced its worst wildfire in state history.
