“Potential Life-Threatening Flooding” Prompts Evacuations On Hawaiian Island, Dam At “Imminent Risk Of Failure”

A dam could potentially collapse because of the flooding, local officials warned.

“WAHIAWA DAM HAS NOT FAILED BUT IS AT IMMINENT RISK OF FAILURE. Potential life-threatening flooding of downstream areas,” Oahu Emergency Management said.

“Evacuation order still in effect,” it added.

HNL Alert: 09:00 AM 03-20-2026 – WAHIAWA DAM HAS NOT FAILED BUT IS AT IMMINENT RISK OF FAILURE. Potential life-threatening flooding of downstream areas.

Evacuation order still in effect. Map: https://t.co/fl1PGwuFJx LEAVE downstre https://t.co/0JFlHmFQip pic.twitter.com/zisr9gJOlQ

— Oahu Emergency Mgmt. (@Oahu_DEM) March 20, 2026

ABC News explained further:

Hawaii Gov. Josh Green said the Hawaii National Guard has been activated and other resources are being deployed across Oahu amid the “severe storm.”

“We are coordinating closely with state and county partners to support evacuations, open shelters, and keep our communities safe,” he said on X.

The latest flood threat comes a week after a damaging flood event that washed away roads and damaged homes.

A flash flood emergency was issued for northern Oahu earlier Friday for “catastrophic” flooding. Local emergency personnel had reported “life-threatening flash flooding” early Friday across northern Oahu, according to the National Weather Service in Honolulu.

“Floodwaters have cut off road access in and out of Haleiwa, and widespread flooding of roadways and low-lying areas is ongoing,” the NWS said, warning that “significant runoff continues to produce high water levels and dangerous flooding impacts.”

“The north shore of Oahu received more than a foot of rain overnight on Thursday, causing intense flooding,” FOX Weather stated.

“National Weather Service Honolulu issued a flash flood warning within a Flash Flood Emergency for Honolulu County, due to an imminent dam collapse. Evacuations are underway in Waialua and Haleiwa for the risk of threatening flooding,” it added.

🚨 BREAKING NEWS: The north shore of Oahu received more than a foot of rain overnight on Thursday, causing intense flooding. National Weather Service Honolulu issued a flash flood warning within a Flash Flood Emergency for Honolulu County, due to an imminent dam collapse.… pic.twitter.com/gdYAL50CSh

— FOX Weather (@foxweather) March 20, 2026

More from Honolulu Star-Advertiser:

The water level in the Wahiawa reservoir, also known as Lake Wilson, has been rising since Thursday night and reached 85.1 feet as of 9:15 a.m., according to the U.S. Geological Survey.

Ahead of last week’s Kona-low storm, the dam’s owner, Dole Food Co. Hawaii, deployed a portable AquaDam barrier to temporarily increase the dam’s height to 90 feet from 88 feet.

The dam also has a spillway to safely discharge water at the 80-foot level into a lower portion of Kaukonahua Stream. Last week, spillway runoff began at about 1:45 p.m. on Friday and continued through Sunday afternoon, according to Dole.

Dam safety regulators with the state Department of Land and Natural Resources have warned for years that the spillway at the dam, which was originally built in 1906 and rebuilt in 1921, is too narrow to handle a “Probably Maximum Flood.”

USGS reported that the water level in the reservoir behind the dam during the last storm peaked at 82.8 feet last Friday, and then gradually receded to 78.8 feet on Thursday before beginning to rise last night due to more rain.