HONOLULU — Crews in Honolulu started evaluating damage after a surprise downpour sent floodwaters surging through a neighborhood in the Manoa Valley area east of downtown, adding to a stretch of storms and flooding that have pummeled Hawaii for more than two weeks. The flooding came Monday when several inches of rain fell in a localized burst, sweeping away parked cars and leaving thick reddish volcanic mud across much of the area, officials said.
Residents described how quickly conditions changed. Andrew Phomsouvanh, who recorded video of streets transformed into a rushing flow of water, said, “I was shocked to see how much flash flooding there was in my area,” adding, “The water just keeps coming.” Maile Mills said she watched water reach the door handles of the Honda Civic she had parked in front of her Manoa office building, pushing the car onto the curb and leaving the vehicle totaled.
Mills said the flooding spread across the street like a moving pond, telling reporters, “It looked like rubber ducks in a pond,” and describing how “All the cars started to float.” She said silt and muddy water covered parts of the interior and the engine compartment.
National Weather Service forecaster Cole Evans said the intensity of the downpour even surprised meteorologists. He said the models used to forecast storms are not good at predicting how much moisture can remain in systems such as a powerful winter storm feature referred to as a “Kona low.” Evans said Tuesday, “When you think it’s over, it’s not quite over,” as the system moved off to the east and officials assessed whether further bursts were likely.
The rainfall also varied sharply over short distances. The downpour dumped 2 to 4 inches of rain per hour, but one rain gauge in the upper part of the Manoa Valley recorded 6 inches in an hour while the airport a few miles away measured just one-hundredth of an inch. Honolulu Mayor Rick Blangiardi said earlier in the day the skies were sunny and called the event a “classic rain bomb,” saying, “We had no warning,” as he toured the damage.
Officials said flood impacts extended beyond the immediate neighborhood. Authorities reported hundreds of homes on Oahu’s North Shore were damaged by last week’s flooding, and they said the new round came as some areas already had soil saturated by downpours from storms a week earlier. Honolulu and state agencies said there were no immediate reports of deaths or serious injuries, but more than 230 people had to be rescued, with floodwaters pushing houses off their foundations and swamping cars and damaging walls, floors and counters.
Evacuation orders were issued for about 5,500 people north of Honolulu, and some residents fled on surfboards when water reached waist or chest height, authorities said. Farms across the state reported more than $17 million in damage as of Tuesday, according to a survey conducted by Agriculture Stewardship Hawaii, the Hawaii Farm Bureau and other organizations.
Gov. Josh Green said the storm’s overall cost could top $1 billion, including damage to airports, schools, roads, homes and a Maui hospital in Kula. Green’s office said Tuesday he submitted a major disaster declaration request to the Trump administration. Molly Pierce, a spokesperson for the Oahu Emergency Management Agency, said that along with volunteers and public workers, a contract company had arrived to begin collecting, sorting and removing large piles of debris.
Pierce described the latest flooding as “extremely unusual,” and said officials were “cautiously optimistic” Tuesday that the rains were finally ending. She said, “Most of us have not seen something that just keeps going like this,” and added, “We feel like we keep getting punched down. But we’ll keep getting back up.”