Hawaii sees worst flooding in 20 years as dam risk and more rain raise concerns

Rescue Efforts: No deaths were reported and no one was missing, though about 10 people were hospitalised with hypothermia, Green said. Rescue crews searched by air and water for stranded residents, but the work was slowed because some people flew personal drones over flooded areas, said Ian Scheuring, a spokesperson for Honolulu, as emergency teams tried to reach those needing help.

Camp Evacuation: The National Guard and Honolulu Fire Department airlifted 72 children and adults who had been attending a spring break youth camp at Our Lady of Kea’au on Oahu’s west coast. The camp was on high ground, but officials decided not to leave them there, the mayor said. Green said the flooding was the most serious since the 2004 floods in Manoa.

Damage Reports: Dozens, possibly hundreds, of homes were damaged, but officials had not fully assessed the destruction, Honolulu Mayor Rick Blangiardi said. About 5,500 people were under evacuation orders. Officials said the damage was caused by heavy rain falling in a short time on already saturated ground, which led to fast-rising floodwaters across several areas of Oahu.

Heavy Rain: Parts of Oahu received 8 to 12 inches of rain overnight, while Kaala, the island’s highest peak, received nearly 16 inches in one day, the National Weather Service said. More rain was expected, with 6 to 8 inches forecast over the next two to three days as Kona low storm systems continued bringing moisture over the islands.

Climate Factor: Kona lows, which bring moist air from southerly winds, were responsible for heavy rain over the past two weeks. Experts said the intensity and frequency of heavy rain in Hawaii have increased due to human-caused global warming. Officials were also closely monitoring the Wahiawa dam, which they said was at risk of possible failure if water levels rose again.

Dam Concerns: Water levels at Wahiawa dam dropped by late Friday but had risen overnight from 79 feet to 84 feet, close to its capacity. The dam was built in 1906, rebuilt after a 1921 collapse and is considered high hazard potential. The state plans to acquire and repair it from Dole, which has been cited for safety issues. Hawaii regulates 132 dams, many built for sugar irrigation.