Glacial Outburst Flooding

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Floodwaters from Juneau’s glacial outburst are receding. The flood reached a record-breaking crest of 16.65 feet at about 8 a.m. Wednesday.

The temporary levee the city installed along the Mendenhall River this year protected hundreds of homes nearby. But water still leaked through some sections and flooded several streets.

In the middle of Meander Way, Sean Smack tugged a raft through muddy floodwaters. He ferried diesel jugs to neighbors so they could run generators to pump the water from their homes since power was cut Wednesday morning as the river level rose.

“The Meander Way water taxi service — once a year, have no fear,” he said.

He delivered a jug to Locke and Melissa Brown’s house. Water from their crawl space flowed through a bright green garden hose down their porch steps.

The Browns have HESCO barriers stacked up in their backyard. But water worked its way through the barriers and rose through storm drains, hitting a handful of homes at the end of Meander Way.

The Browns were glad that the barriers are there, even with the seepage. This is the third year in a row their home has flooded.

“If they weren’t here, it would have been catastrophic for us,” Locke Brown said.

It’s not as bad this time. But he says they want a long-term solution before they have to sell their home in a few years. Melissa is on active duty in the U.S. Coast Guard.

“We’re going to be doing this for five years in total, and then we’re forced to move on military orders,” he said. “How are we going to sell our house?”

Around the corner, Andrew Hills walked along the grey pool in the middle of Northland Street with his toddler, Waylon, up on his shoulders. Their house got hit by the flood last year, but this year it was spared.

“This is awesome. I could not be happier,” Hills said. “I feel terrible for the people at the end of Meander, but, you know, really happy it didn’t hit us.”

He said he spent the night walking the streets and saw the barriers leaking.

At a press briefing Wednesday morning, Juneau City Manager Katie Koester said the barriers were largely a success.

“I know we’re not entirely out of the woods, but the HESCO barriers really have protected our community,” Koester said. “If it weren’t for them, we would have hundreds and hundreds of flooded homes.”

Building the levee was a controversial process, and it is considered a stop-gap solution. It’s only meant to work for around a decade, and the city doesn’t know how it would perform in floods higher than 18 feet. Experts still don’t know whether that could happen. This year’s record-breaking crest was more than half a foot higher than last year’s peak of 15.99 feet, which was also a foot higher than the previous year.

City officials are still assessing the damage and monitoring areas that saw some flooding, including parts of Meander Way, Meadow Lane, Marion Drive, Parkview Court, Center Court, View Drive, Long Run Drive, Betty Court, Gee Street and the Safeway parking lot.

Christopher Goins with the Alaska Department of Transportation said Back Loop Bridge was damaged by tree strikes and erosion. The bridge was closed to traffic Tuesday night.

“We are beginning to lose portions of the road associated with that abutment there, and that’s the main support where we have piles that go into the ground that hold up the bridge sections themselves,” he said Wednesday morning, adding that the bridge should be fine with some repairs.

The current swept away tons of trees from the riverbank, including one that crushed a HESCO barrier. The city reinforced it with massive sandbags called supersacks.

Nicole Ferrin, the warning coordination meteorologist for the National Weather Service in Juneau, noted the significance of this flood.

“This is a new all-time record-high crest for the Mendenhall Lake and river system,” Ferrin said.

The crest happened sooner than initially predicted. On Tuesday evening, the National Weather Service updated the forecast from an expected peak Wednesday afternoon to earlier that morning. Aaron Jacobs, senior service hydrologist at the agency, said that’s because rainfall from the prior few days masked when Suicide Basin started to release.

“It really hides the signal that we would be looking for if water was coming from Suicide Basin,” he said.

Jacobs said it now looks like the release began sometime on Monday morning.

Just outside the city’s emergency shelter on Floyd Dryden campus, Shari Weimer smoked a cigarette as sunshine broke through the fog. She and her husband Carl evacuated from Lakeview Court at around 10 p.m. Wednesday night.

“I’m right one street over from the river, and I just chose to evacuate because my life is worth more than home,” she said.

Their house flooded the past two years. This time, with a higher peak and concerns about the temporary levee, Shari said she didn’t want to deal with the panic again.

Just seven people stayed in the shelter overnight. Some residents stayed with friends and family in town, and others stayed home. Capital City Fire/Rescue Assistant Chief Sam Russell said during a Wednesday’s press conference that emergency responders did not need to make any rescues overnight as waters levels rose. 

The Juneau School District postponed the first day of school on Thursday until Friday in order to allow the area time to dry out.

Emergency officials issued an alert Wednesday afternoon that the flood threat had ended and evacuated areas are now open to residents only. The National Weather Service flood warning expires at 8 a.m. Thursday. 

This post has been updated. 

Juneau schools will remain closed Thursday following a record-breaking glacial lake outburst flood event in the Mendenhall Valley. The Juneau School District plans to delay the start of school until Friday.

Superintendent Frank Hauser said at a press conference Wednesday morning a flood warning from the National Weather Service remains in effect until 8 a.m. Thursday.

“We have three schools in the area,” he said. “Delaying the start of school by one day will allow Unified Command staff and safety crews to assess damage in the Valley area.”

The district closed Kax̲dig̲oowu Héen Elementary School, Mendenhall River Community School and Thunder Mountain Middle School Tuesday afternoon as a safety precaution for staff. Hauser said there isn’t any damage reported at the schools in the flood zone as of Wednesday morning. 

All school activities, including the first day of high school for ninth graders, are also canceled Wednesday.

Hauser said afterschool child care such as the Relationships and Leadership Learning for Youth program, or RALLY, will not be provided while schools are closed.

The district will continue to update families through automated calls, texts, emails, the Juneau Schools app and the district website.

The flood reached a record-breaking crest of 16.65 feet at about 8:00 a.m. Water continues to seep into Valley neighborhoods.

The HESCO barriers stacked in backyards along the river are blocking many homes from flooding, but water is seeping under and through the barriers on parts of Marion Drive, Killewich Drive, Meander Way and Riverside Drive. View Drive is flooded — that street is not protected by a barrier.

Some roads along the river have pooled with water, with multiple homes pumping water out of their crawlspaces. Alaska Electric Light & Power has cut power to some flood-affected streets. 

Despite seepage, Ryan O’Shaughnessy, the city’s emergency program manager, says “there is no reason to believe there is imminent failure” of the HESCO barriers.

Some residents are reporting that water is reaching their properties when they hadn’t in prior floods. The city is helping residents pump out water from yards that have flooded.

The city is deploying supersacks to one section of the barriers where it appears a tree struck it — but no water has broken through at that point. The city continues to ask people to stay away from the area, and recommends evacuating immediately.

Find the latest news on glacial outburst flooding and resources for how to prepare at ktoo.org/flood.

Listen to this story:

Juneau’s annual glacial outburst flood started Tuesday morning and is expected to peak Wednesday morning. Experts predict it could be the largest flood on record. 

This year, the flood will test a temporary levee that the city installed this spring. But not every street in the flood zone is protected by the barrier. 

As Malachi Thorington and Elizabeth Figus packed their blue chevy truck Tuesday afternoon to stay at a friend’s house, the sound of the rising river rushes behind their house. 

The first floor of their home flooded the past two years. Thorington said he knows the drill now.

“Just kind of dealing with the present, at the moment, basically going into damage mitigation mode. Try not to feel anything, just try to go as mechanical as possible,” he said. “There will be things that are lost, and I really hope that other people have taken this seriously.”

The City and Borough of Juneau issued an evacuation advisory Tuesday morning as glacial outburst floodwaters began to rise in Mendenhall River. Some residents are heeding the warning, but others are hunkering down at home. Everyone is waiting to see whether preparations made over the past year will protect their homes from a third catastrophic flood. 

At the end of View Drive, a colossal man-made berm separates Carol and Don Habeger’s house from the cold rushing water. 

Walking along the berm, they see a young spruce on the other side of the river crash into the torrent. Along with a couple of neighbors, the Habegers spent the past month erecting the levee around their home of more than 20 years. The city constructed a separate temporary levee farther downriver. 

“We are trying to save our property — we are trying to save our equity,” he said. 

Imagine 400 truckloads of boulders, rocks and fine sand stacked around 12 feet high. The couple plans to stay home, even as the river is projected to reach a record-breaking level of 16.6 feet.

“I was going to invite folks, but I don’t want the liability,” he said.

The Mendenhall River started flooding annually more than a decade ago, but for a while it was treated as more of a curiosity than a cause for concern. Then, in 2023, everything changed when a record-breaking 15-foot flood hit the Valley. A couple dozen homes flooded. 

The 2024 flood broke the record again, this time cresting at 16 feet, and it was catastrophic. Nearly 300 homes flooded. The federal government declared it a major disaster.

Glacial outburst floods are not uncommon in Alaska, or in other places with glaciers around the globe. But Juneau, Alaska is the only city in the U.S. that lives beneath their threat.

Suicide Basin is the source. It’s a slurry of water, icebergs and silver silt that swells with rain and meltwater in the spring and summer. 

Climate change has sharpened the risk of glacial outburst floods. In Juneau, their size has increased as the glacier has melted more rapidly. Scientists today are trying to figure out how big the floods can get.

At a press briefing Tuesday morning, Warning Coordination Meteorologist for the National Weather Service Nicole Ferrin said the river was already unusually high because of rain from the past few days. 

“This will be a new record based on all of the information that we have,” she said. 

The city is encouraging residents to evacuate the area, but it’s not a mandatory order. On Monday, the city hung nearly 900 informational door flyers in Mendenhall Valley neighborhoods in the flood zone and launched a flood information hotline.

Residents can see whether their home is in the flood zone by visiting Juneauflood.com. Though city officials say they’re confident the barriers will hold, they don’t want people to test it with their lives. The area includes homes along the river, down Riverside Drive to Safeway, past Glacier Highway and near the Juneau International Airport.

Capital City Fire/Rescue Assistant Chief Sam Russell said emergency responses will become more difficult as the river rises. He asked residents to stay away from the river and bridges as much as possible.

“As the flood goes up, our ability to navigate the waters goes down due to the debris that flows down through it makes navigating the river with a boat very, very difficult,” he said. 

At the Floyd Dryden campus, the American Red Cross is prepared to receive people who follow the evacuation advisory. 

Michael Downs is the Juneau district ranger for Tongass National Forest. He closed down the Forest Service campground on Mendenhall Lake this morning. The few RVs that were there are now parked at the campus.

He said the Forest Service is also managing disaster tourism in the area – people wanting to get an in-person glimpse of the flooding. He said all lakeside trails and roads by the Visitor Center and near Skater’s Cabin are closed. Anyone who violates that could face consequences.

“This year, we just did a Forest Order that they can be fined up to like, $5,000 so [it’s] got a little bit more teeth this year,” he said. 

He said on top of being a safety concern, it’s to protect the employees. 

“Their homes are impacted, and they work there, and people are oohing and ahhing about their disaster and it’s yucky,” he said. “I prefer people don’t come in there.” 

Floodwaters are expected to peak Wednesday afternoon, and then drop through Thursday morning. 

This story has been updated to add more context about glacial flooding and reflect the latest National Weather Service forecast. 

Find the latest news on glacial outburst flooding and resources for how to prepare at ktoo.org/flood.

Hundreds of people in Juneau’s Mendenhall Valley are living on the front line of a climate change disaster they didn’t see coming. This is Outburst, the story of how glacial outburst flooding has escalated faster than human imagination – and public policies to protect people.

The KTOO newsroom takes you from the floodwaters to the glacier’s edge to uncover why the annual floods happen, how they got out of control and what can be done to keep Juneau safe.

Suicide Basin is a slurry of water, icebergs and silver silt between jagged peaks, and it’s the source of Juneau’s annual glacial outburst flood. The Mendenhall Glacier revealed the basin as its retreat reshapes parts of Juneau’s topography.

Researchers say that understanding the basin and others like it is key to a better knowledge of  future glacial outburst floods. The second episode of Outburst takes us from the past, when early Mendenhall Valley residents were among the first record keepers of area floods, to  the present to hear how scientists are figuring out how big the danger could get. 

KTOO’s Alix Soliman is our guide from the basin’s edge to the Mendenhall River floodplains to understand what we know — and which questions are left unanswered.

Update, 3:52 p.m. Tuesday:

The Juneau School District is canceling all extracurricular and school-sponsored events Tuesday and Wednesday. 

According to a district press release, this includes the first day of school for high school freshmen at Juneau-Douglas High School: Yadaa.at Kalé scheduled for tomorrow.

The district is also closing Kax̲dig̲oowu Héen Elementary School, Mendenhall River Community School and Thunder Mountain Middle School at 4 p.m. today until the City and Borough of Juneau issues an all clear. District administrators and staff are working in the buildings until the closure.

The district has not yet made a decision on closing schools on Thursday. It will make an announcement by Wednesday at noon. If any schools need to close, the district will close all campuses.

The district will continue to update families through automated calls, texts, emails, the Juneau Schools app and the district website.

Update, 10:45 a.m. Tuesday:

The Juneau School District will make a decision on closing schools by Wednesday at noon. Superintendent Frank Hauser said during a press conference Tuesday the district is requesting families update their contact information in PowerSchool to ensure they receive the most up-to-date information from the district.

Original story:

With school set to begin on Thursday, the Juneau School District announced Monday that it plans to close all schools this week if any campuses are impacted by glacial outburst flooding.

The glacial lake that releases water annually is full. That means the Mendenhall River could flood at any time this week, but it’s not clear exactly when that will happen.

Three schools in the Mendenhall Valley – Kax̲dig̲oowu Héen Elementary School, Mendenhall River Community School and Thunder Mountain Middle School – could experience flooding.

At a press conference Monday, Deputy City Manager Robert Barr said one of the reasons for closing all schools is because of district staff who may live in the flood zone.

“They have teachers, and they have staff that are in that flood inundation, that are going to be in that 17-foot impact area that we’ll be recommending an evacuation for,” he said. “From their point of view, [it’s] hard to operate the rest of the district when their faculty, when their staff, are potentially impacted.”

In an email to KTOO, Juneau School District Chief of Staff Kristin Bartlett wrote additional road congestion from school related traffic and road closures cutting off people returning home as other reasons for the plan.

In a press release, the district said it plans to announce any closures before the school day begins if possible. But it’s also prepared to evacuate schools as needed.

Students and staff will move to a safe location outside of the evacuation zone. Only guardians and emergency contacts listed in PowerSchool will be able to pick up students.

Students who take the bus and live in the evacuation zone may also be taken to a different location for pickup if they attend a school outside of the flood zone. Photo ID is required to pick up students. 

The district’s website has information on flood procedures. District leadership says families can receive updates through the Juneau Schools app. The district will also email updates to families through its Blackboard communications system.

Find the latest news on glacial outburst flooding and resources for how to prepare at ktoo.org/flood.