LEILA FADEL, HOST:
Every year for about a decade, the Mendenhall River in Juneau, Alaska, has flooded from meltwater buildup on a nearby glacier. Those floods were minor until 2023, when a couple of dozen homes in Juneau were damaged. Last year, it was a lot worse, flooding 300 homes. Now the flood has hit Juneau yet again. City officials are still tallying the damage, but they say a new temporary levee protected many homes. KTOO reporter Alix Soliman has the story.
ALIX SOLIMAN, BYLINE: These floods are glacial outbursts. A deep pool on the Mendenhall Glacier swells with rain and meltwater during the warm seasons, then ruptures the ice dam holding it in place. Then it floods the valley below. Glacial outburst floods are not uncommon in Alaska or in other places with glaciers around the globe, but Juneau is the only U.S. city that deals with this danger.
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SOLIMAN: This year's flood reached its peak Wednesday morning. As it receded, riverside homeowners Melissa and Locke Brown pumped water out of their crawl space through a bright green garden hose.
MELISSA BROWN: Last year, we had 10 inches of water in the house, 3 feet of water in the garage.
SOLIMAN: This year was better. Only the crawl space got wet. That's because of a levee the city built that stands between their house and the river. It's made of HESCO barriers, which are steel baskets filled with sand. Even though the water seeped through, the Browns say the barriers helped.
LOCKE BROWN: If they weren't here, it would've been catastrophic for us.
SOLIMAN: At a press briefing Wednesday, Juneau's city manager, Katie Koester, said the barriers were largely a success.
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KATIE KOESTER: The HESCO barriers really have protected our community. If it weren't for them, we would have hundreds and hundreds of flooded homes.
SOLIMAN: The levee is considered a stopgap solution. It's only meant to work for about a decade, and the city doesn't know how it would perform in floods higher than 18 feet. So far, the floods haven't been that high, but each year, they've gotten bigger - 15 feet, then 16. This year, more than 16 1/2. Glaciologists say that human-caused climate change is exacerbating the size of these floods in Juneau. As the Mendenhall Glacier melts back, the pool grows, so it can release more water. Eventually, the glacier could retreat so much that the pool disappears, but scientists don't yet know when.
For NPR News, and with help from Clarise Larson, I'm Alix Soliman in Juneau.
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