Outburst: A new KTOO series coming this August

It’s been almost two years since Juneau’s glacial outburst flood got out of hand. 

On that August day, the water level rose swiftly on the Mendenhall River. That wasn’t unusual. Local experts had been tracking water levels in Suicide Basin — the glacial lake high up on Mendenhall Glacier that fills with rain and meltwater every summer — for years and gave ample notice of the annual release.

But unlike in previous years, the water level rose to nearly 15 feet.

“There is no comparison,” National Weather Service Meteorologist Nicole Ferrin told KTOO at the time. “We’re two feet over our last record.”

One unoccupied house crashed into the swollen river. Other homes had their foundations exposed by the eroded riverbank.

A house and condo buildings in the 4400 block of Riverside Drive hang precariously over the Mendenhall River after their foundations were eroded away during record high water from a glacial outburst flood on Saturday August 5th, 2023. (Mikko Wilson / KTOO)
A house and condo buildings in the 4400 block of Riverside Drive hang precariously over the Mendenhall River after their foundations were eroded away during record high water from a glacial outburst flood on Saturday, Aug. 5, 2023. (Mikko Wilson / KTOO)

The event caught everyone off guard, including those of us in the newsroom. Aside from some erosion and moderate flooding that threatened a few homes along the river, the annual outburst flood was in many ways more of a novelty up to that point.

The next year, the flood was even bigger and the consequences were much more serious. Hundreds of homes flooded when the river crested at 16 feet. 

KTOO Climate and Weather Reporter Anna Canny covered the aftermath of both record-breaking events. Last fall, she proposed a series examining the floods and secured funding from the Alaska Center for Excellence in Journalism to help make it happen.

KTOO reporter Anna Canny interviews emergency personnel along Mendenhall River during the August 2024 glacial outburst flood. (Photo by Clarise Larson/KTOO)

Now, as Juneau residents and officials prepare to take on a potential third year of flooding, our newsroom has a new series, Outburst, that takes stock of the evolving threat and efforts to keep residents safe.

Although Anna left Juneau at the beginning of the year to pursue new opportunities, this series would not have been possible without her. 

Climate and Environment Reporter Alix Soliman joined the newsroom in February and dove headfirst into flood reporting, picking up right where Anna left off. She’s reported extensively on the construction of HESCO barriers along sections of the river and preparations ahead of this year’s flood and hosts the series. 

ACEJ’s grant supported this four episode series, as well as outreach efforts to make sure information about the flood gets to the people who need it. Those included a community public safety barbecue this July and a set of maps that show the evolving course of the river, its flood paths and the recession of the Mendenhall Glacier.

Outburst premieres in early August. Find it here at ktoo.org/outburst, on the radio and wherever you get your podcasts.

 

Mendenhall Valley residents and local organizations gather to discuss glacial outburst flood preparation at Riverside Rotary Park on Thursday, July 17, 2025 for KTOO’s community barbecue. (Photo by Will Mader/KTOO)

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