In Juneau, It's Like a Fast-Draining Bathtub

Rising meltwater from Alaska's Mendenhall Glacier has set off unprecedented flooding and emergency evacuations in the state capital of Juneau. Water recently began escaping a glacial basin and pouring into the Mendenhall River, prompting the National Weather Service to issue a flood warning. The Juneau city government likened the process to a bathtub suddenly draining: When the melting water builds up behind the glacier, it eventually finds an escape route, resulting in a rapid and sometimes disastrous outflow, per the BBC. By Wednesday morning, water levels had climbed above 16 feet, surpassing the record of 15.99 feet set in August 2024, when the riverbank eroded and homes were washed away, per USA Today and the Anchorage Daily News.

The glacier, located about 12 miles from downtown Juneau, draws hundreds of thousands of visitors each year. But for local residents, glacial lake outburst floods—known as GLOFs—have become a recurring threat since 2011. The state governor, Mike Dunleavy, declared a disaster over the weekend, citing the looming risk of "catastrophic flooding." The water level was expected to peak around 16.25 feet to 16.75 feet on Wednesday morning, per USA Today. The evacuation zone includes numerous homes and a school along the river's banks, per Alaska's News Source. With floodwaters expected to remain high, the state will be on the alert for damage for several days. (The rate of ice melt in the Juneau Ice Field has doubled in recent years.)