UPDATE: 9 a.m.

The Honolulu Department of Emergency Management has clarified that “Wahiawa Dam has not failed but is at imminent risk of failure.”

“Potential life-threatening flooding of downstream areas,” the agency said in a bulletin. “Evacuation order still in effect. LEAVE downstream area NOW! Heavy traffic-Please carpool.”

As of 9 a.m., the water level in the Lake Wilson reservoir created by the dam, in addition to the amount of rain projected to fall in the area today, is enough for the dam to possibly fail, according to Ian Scheuring, a spokesperson for Honolulu Mayor Rick Blangiardi.

Scheuring said the most likely scenario of a dam failure is water flowing over the top of the dam despite a spillway that channels water above a relatively high level out of the reservoir and downstream.

“That in and of itself can be extraordinarily dangerous,” he said.

 

An unlikely scenario, Scheuring added, would be for part of the earthen dam to break.

The dam is designed to hold back around 2.6 billion gallons of water.

City officials are advising people who are evacuating Waialua and Haleiwa due to the Wahiawa Dam failure danger to go to city evacuation centers in Wahiawa District Park and Leilehua High School instead of Waialua High School, where an evacuation center is being closed due to the dam failure danger.

The Waialua High School evacuation center had about 185 people earlier this morning, and they are being shuttled to the safe evacuation centers.

8:40 a.m.

Evacuations are now underway on Oahu’s North Shore after city officials issued an urgent alert warning that failure of the Wahiawa Dam is in progress or expected, dramatically escalating an already dangerous flooding situation.

The Honolulu Department of Emergency Management issued an “Evacuate Now” order at 8:34 a.m. for areas downstream of the Wahiawa Dam, citing the potential for “life-threatening flooding and catastrophic amounts of fast moving water.”

“TAKE ACTION – EVACUATE NOW,” the alert said. “DAM/LEVEE FAILURE IN PROGRESS OR EXPECTED at Wahiawa Dam.”

The mandatory evacuation covers parts of Haleiwa and Waialua, including areas of Haleiwa between Puuiki Street and Kamehameha Highway, and parts of Waialua from Kukea Circle to Otake Camp. Officials warned that conditions could change rapidly as water moves downstream along the Kaukonahua Stream corridor.

Emergency managers said traffic is already heavy and urged residents to carpool if possible. Drivers are being directed away from the flood zone using Kamehameha Highway toward Wahiawa, then onto Kamananui Road and Wilikina Drive, while warning not to use Kaukonahua Road. The Karsten Thot Bridge on Kamehameha Highway is closed, forcing all traffic onto alternate routes.

Assembly areas have been opened at Wahiawa District Park, Leilehua High School and Kahuku Elementary School, while the Waialua High and Intermediate site is closed due to flooding.

Officials are urging residents in the evacuation zone to leave immediately with only essential items, gather family members and assist neighbors if it can be done safely. They also warned people not to walk or drive through moving water and to stay out of evacuated areas until authorities say it is safe to return.

The evacuation order comes shortly after the National Weather Service warned of a possible dam failure and ongoing flash flooding across northern Oahu, with multiple alerts in effect as heavy rain continues to move across the island.

The City and County of Honolulu is closing the emergency shelter at Waialua High School due to worsening flooding on the North Shore, officials said.

Evacuees who would normally go to Waialua High are being redirected to Wahiawa District Park, which remains open. About 180 people and 45 pets were at the Waialua shelter as of the latest check, and authorities are coordinating their relocation.

Honolulu City buses are assisting with evacuations, and law enforcement is on-site to help secure and transport shelter occupants.

Officials said 8 to 12 inches of rain have fallen across the North Shore in the past 12 hours, triggering severe flooding and an active search-and-rescue response. Crews from Honolulu police, fire and Ocean Safety are using jet skis to reach people stranded by floodwaters.

There have been reports of homes being swept off their foundations, though no confirmed reports of individuals being washed away. Rescuers are actively working to reach residents trapped on higher ground.

While some flooding has been reported on the Waianae Coast, officials say the most severe conditions remain on the North Shore.

Door-to-door rescues are underway — with some people rescued froom rooftops on the North Shore — and others have been transported to Wahiawa Hospital with hyperthermia, Gov. Josh Green reported this morning on Hawaii News Now.

“This is spring break, there are 70 people surrounded by water at a camp on the North Shore, many of them kids were…they were not yet evacuated but they were safe,” the governor said.

According to the governor, the Hawaii National Guard will be assisting as soon as it can get into the affected areas.

Some of the roads on the North Shore are impassable. Emergency response vehicles are having trouble moving through waters, Green said.

The flash flood warning has been extended to 11 a.m.

“All resources have been mobilized,” the governor said.

Because rescuers are encountering people with hyperthermia, crews “are going door to door because some may be in crisis and not able to get out,” Green said.

“We’re praying that the rain subsides. It’s a precarious situation.”

The governor said residents should prepare to leave the region. “We want to do in advance before it becomes too dangerous. “

The Wahiawa Dam spillway is reaching dangerously high levels, with “a lot of water spilling everywhere,” Green said.

“People are going to have to be rescued today…The biggest concern if water goes over and compromises the structure of the dam. We’re asking people to calmly move out of the area and evacuate.”

8:30 a.m.

Flooding danger escalated sharply across Oahu today as a new flash flood warning tied to a possible dam failure was issued alongside a broader flood advisory covering much of the island.

The National Weather Service said at 8:22 a.m. that “local law enforcement reported the imminent failure of Wahiawa Dam,” triggering urgent alerts for communities downstream.

The warning focuses on the Wahiawa Dam along the Kaukonahua Stream, where officials warned of sudden and dangerous flooding. The agency said flash flooding from the imminent failure of the dam is expected to affect areas downstream, including Waialua and Haleiwa, and noted that flooding is already being observed along the stream. The warning is in effect until 1:15 p.m. and could be extended if conditions persist.

At the same time, forecasters issued a flood advisory for all of Oahu until 11 a.m., signaling widening impacts beyond the North Shore as heavy rain spreads. Radar at 7:57 a.m. indicated rainfall rates of 1 to 2 inches per hour over south and east Oahu, with additional bandsof rain expected to move through the area during the morning hours.

The advisory covers urban Honolulu and surrounding communities, where officials warned of ponding on roadways, flooding in poor drainage areas and rapid rises in storm water channels and drainage ditches as runoff increases.

The latest alerts add to a Flash Flood Emergency already in place for northern Oahu, creating a layered and rapidly evolving situation across the island. While rainfall has varied in intensity, the weather service warned that additional heavy rain could quickly worsen flooding conditions in multiple regions.

Residents are urged to move to higher ground if they are near streams or downstream areas, avoid travel unless evacuating and stay clear of waterways and flood-prone roads. Officials said both alerts may need to be extended beyond their current end times if flooding continues.

7:45 a.m.

Flooding remains life-threatening across northern Oahu this morning as forecasters extended a flash flood emergency through late morning, warning that conditions could worsen again.

The National Weather Service said at 7:43 a.m. the flash flood warning for Oahu is now in effect until 11 a.m., with “widespread life-threatening flash flooding effects continuing,” especially in Haleiwa and Waialua.

“This is a flash flood emergency for Northern Oahu. This is a particularly dangerous situation. Seek higher ground now!” the agency said in an urgent bulletin that triggered an Emergency Alert System activation request.

While rainfall rates briefly eased, officials warned that runoff is still driving rising water levels across the region.

“Although rainfall rates have temporarily decreased, significant runoff continues to produce high water levels,” the weather service said, noting the Wahiawa Reservoir continues to rise.

That poses an ongoing threat downstream, particularly near Otake Camp in Waialua, where additional rises “could further exacerbate” flooding.

Forecasters say the break may be short-lived.

“Additional bands of heavy rainfall moving in from the southwest will continue over the area throughout the day,” the agency said, warning of renewed flooding as conditions evolve.

On windward Oahu, heavy showers producing 1 to 2 inches of rain per hour are expected to continue, keeping streams elevated in areas including Waiahole Stream, Waikane Stream and Kahana Stream.

Runoff is already affecting low-lying roads and communities.

Emergency officials warned of severe consequences across much of northern Oahu, including areas along and north of a line from Waianae Valley to Mililani Mauka to Waiahole.

Impacts include:

>> Major flooding in streams, rivers and neighborhoods

>> Numerous road closures across the North Shore and central Oahu

>> Possible landslides in steep terrain

>> Significant property damage in low-lying areas

The alert is based on stream gauge data, indicating ongoing flooding rather than just radar estimates.

What residents should do now

Authorities are urging immediate action:

>> Move to higher ground now

>> Do not attempt to drive unless evacuating

>> Avoid streams, drainage channels and culverts

>> Be alert for rock and mudslides

Officials cautioned the warning could be extended beyond 11 a.m. if flooding persists.

EARLIER SOVERAGE

A flash flood emergency was declared today for parts of Oahu as life-threatening flooding triggered evacuations on the North Shore.

The National Weather Service said the flash flood emergency — its most severe flood alert — covers northern Oahu, including Haleiwa and Waialua, where floodwaters have cut off road access and inundated low-lying areas, through 8 a.m.

The Honolulu Department of Emergency Management issued an evacuation order for Haleiwa and Waialua, warning residents to leave immediately or move to higher ground or the highest floor of their homes.

Emergency officials described extremely dangerous flooding conditions in both communities, with high water levels at Wahiawa Dam adding to downstream flood risks.

Assembly areas Opens in a new tab opened at 5 a.m. across Oahu for displaced residents and visitors, providing outdoor gathering spaces for those unable to return home. Officials said the sites are not staffed but may have restroom access if available, and pets are allowed if leashed or in carriers.

Evacuation Bus Information: TheBus is mobilizing evacuation bus resources to Waialua/Haleiwa as of 6 a.m. and can direct them to any safe staging point in Haleiwa. Deployed buses will be marked with “EVACUATION” on signage and may be flagged down at any safe location (not necessarily at bus stops) to board and evacuate. No fares required.

Service for The Bus is disrupted in Waialua and Haleiwa on the following routes: No service on Route 521. Routes 52 and 60 are operating only to Weed Circle in Haleiwa. Routes 60 and 88A service impacted: No service between Waimea Valley and Kahaluu (Kamehameha/Kahekili at Hygienic Store).

Those who need to evacuate should bring a Go Bag with essential supplies, including medications.

Authorities urged the public not to walk or drive through flooded roadways and to stay out of evacuation areas until officials say it is safe to return.

Emergency officials reported widespread flooding of roads and neighborhoods across the North Shore, with access in and out of Haleiwa cut off.

Forecasters warned that additional bands of heavy rain moving in from the southwest could cause water levels to rise again and worsen flooding.

Water levels remain elevated at Wahiawa Reservoir, also known as Lake Wilson, and Helemano Reservoir, raising concerns about continued flooding in downstream areas near Waialua.

On the windward side, heavy showers continue to move through areas including Waiahole, Waikane and Kahana, where streams are running high and flooding may affect roads and low-lying areas.

The warning comes as a Kona low storm brings multiple rounds of heavy rain across the state through the weekend, with a flood watch in effect for all islands through Sunday afternoon.

A flood advisory was also issued for Molokai, where moderate to heavy rain is causing minor flooding in low-lying areas and along roadways.

Conditions are expected to gradually improve from west to east starting Monday as the storm system moves away from the islands and more typical tradewind weather returns.