Juneau's Suicide Basin Rapidly Filling, Flood Risk Expected Mid-August

Juneau's Suicide Basin, a glacial reservoir adjacent to the Mendenhall Glacier, is rapidly filling and is projected to reach spillover levels by mid-August, raising concerns of flooding in the Mendenhall Valley. Recent data indicates the basin's water level has increased nearly 27 feet over the past week, averaging about 3 feet daily, with current levels at 1,340 feet—still 28 feet below the spill threshold of 1,368 feet. A drone survey by the University of Alaska Southeast revealed the ice dam constraining the basin's water is now 3 feet lower than last year, affecting spill calculations. Historically, Suicide Basin has caused annual outburst floods since 2011, with the most severe occurring on August 6, 2024, damaging property and infrastructure. The last known release was on October 20, 2024. The timing of the next potential flood depends on factors such as temperature shifts and late-summer storms, with early indications suggesting an overflow could occur as soon as the second week of August. Local authorities and residents in flood-prone areas near Mendenhall Lake and River are advised to stay informed via National Weather Service updates and local alerts. Emergency response...