Additional Coverage:
- A glacier outburst is underway in Alaska. It could send a wave of water downstream toward Juneau (cnn.com)
Juneau Faces Potential Record-Breaking Flood for Third Consecutive August
Juneau, Alaska is bracing for potentially devastating flooding for the third August in a row as a glacial outburst from the Suicide Basin threatens the state capital. City officials issued a news release Tuesday urging residents in the 17-foot inundation zone along Mendenhall Lake and River to evacuate immediately.
The outburst occurs when melting snow, ice, and rainwater accumulate in Suicide Basin, eventually overtopping the Mendenhall Glacier and rushing downstream. This glacial lake outburst phenomenon has become an annual threat, increasing in severity since 2011, and particularly since 2023.
The National Weather Service has issued a flood warning, predicting the Mendenhall River will rise several feet by Wednesday. By Tuesday afternoon, the river had already reached moderate flood stage (Level 3 of 4).
Significant flooding was reported in Mendenhall Lake Tuesday evening, with over three feet of water accumulating in some areas. The river is expected to crest at approximately 16.6 feet Wednesday morning, exceeding the record set just last year, and potentially causing life-threatening conditions.
Last year’s outburst resulted in a 15.99-foot crest, impacting over 100 homes and causing unprecedented damage. This year’s predicted crest surpasses even that alarming level.
While a flood barrier installed after the 2024 flood offers some protection, officials are strongly urging residents in the affected area – roughly 1,000 residents and businesses – to evacuate. Senator Lisa Murkowski echoed these concerns, urging residents to heed evacuation warnings.
Alaska Governor Mike Dunleavy issued a preemptive disaster declaration on Sunday to expedite emergency response efforts. This proactive measure aims to position resources and personnel strategically, minimizing the impact and safeguarding the community.
The increasing frequency and intensity of these glacial outbursts are attributed to climate change and the rapid warming of the Arctic region. The rising temperatures cause glaciers to thin and melt, creating conditions ripe for these devastating floods. The Mendenhall Glacier and Suicide Basin have shrunk considerably, transforming parts of the once-icy landscape into a reservoir that fills dangerously each summer.