Aug. 13 (UPI) — Officials in Alaska advised residents to evacuate the state’s capital city Wednesday as a melting glacier is expected to cause major flooding.
The city and borough of Juneau announced at 10:50 a.m. EDT that it “is aware of the presence of water in certain areas” and that anyone within the flood zone of the Mendenhall River should evacuate the area.
The National Weather Service stated Wednesday that the river had crossed into a “Major Flood” stage and was expected to crest sometime around 12 p.m. EDT at a record level of nearly 17 feet.
The flooding is being caused by a “glacier-dammed lake outburst,” or GLOF, which occurs when a lake dammed by ice or a glacial deposit gives way and releases heavy amounts of water into river systems further downstream.
A geological depression near the Mendenhall Glacier known as Suicide Basin is located above Juneau. The glacier naturally dams the basin, but since 2011 has annually caused flooding of the Mendenhall River when it melts.
Outburst flooding in August of last year had caused the river to reach a then-record level of 15.99 feet. As of 10 a.m. EDT Wednesday, the river had already reached 16.17 feet and was still rising.
“This is likely to become a life-threatening situation,” Sen. Lisa Murkowski, R- Alaska, posted to X Tuesday in advance of the weather event.
Alaska Gov. Mike Dunleavy had issued a disaster declaration Sunday “in response to an imminent threat of catastrophic flooding.”
The flood warning is scheduled to remain in effect until 12 p.m. EDT on Thursday.