A basin of rainwater and snowmelt dammed by Alaska's Mendenhall Glacier began releasing floodwater on August 12, 2025, threatening downstream homes and prompting evacuation warnings in Juneau, the state capital. Officials urged residents in affected areas to evacuate as the Mendenhall River crested at over 16 feet, surpassing previous record flood levels. The flooding, described as a glacial outburst flood, marks the third consecutive year of glacier-related flooding in Juneau. Alaska Governor Mike Dunleavy declared a state of disaster in response to the event. Floodwaters breached barriers and inundated neighborhoods, causing urgent safety measures. Authorities and local representatives emphasized the critical nature of the situation and monitored the threat closely. By August 14, waters began to recede, ending the immediate flood threat. The event highlights ongoing concerns about climate change impacts in the Arctic region, where warming accelerates glacier melt and increases flood risks.
The Arctic is the fastest-warming region on Earth. Thawing permafrost releases carbon and methane, while warming spurs Arctic greening. More plants may briefly protect permafrost, but this can’t outweigh the intense warming. Learn more: https://t.co/K1Xj3dBajz https://t.co/syBhnXXTso
The Mendenhall Glacier in Alaska—which has existed for thousands of years—is melting. So much so, that the National Weather Service issued a flood warning and Alaskans are already evacuating their homes. We must pass serious climate reform, before climate change comes for us.
A rush of glacial floodwater swept down Alaska’s Mendenhall River on Wednesday morning, prompting evacuation warnings in parts of Juneau, seeping through flood barriers and flowing into a few neighborhoods. https://t.co/ze4KvYIeTo