• Alaska’s capital, Juneau, faces imminent catastrophic flooding from Suicide Basin above the Mendenhall Glacier.
• State and local authorities have issued disaster declarations and activated emergency operations to protect residents and infrastructure.
• Residents are urged to complete preparations, follow alerts, and be ready for possible evacuation in the 17-foot inundation zone.

Residents of Juneau, Alaska, are on high alert as officials declared a state of disaster on Sunday. This is in anticipation of a potentially catastrophic glacial lake outburst flood (GLOF). The warning comes amid rising concerns over the Suicide Basin, a glacial lake perched above the Mendenhall Glacier. It has reached water levels comparable to the worst floods in recent history.

Governor Mike Dunleavy announced the emergency declaration. He highlighted the urgent need to position state resources and personnel ahead of a possible disaster. “Our priority is clear: we act early to protect lives, homes, and essential services,” Dunleavy said. He emphasized that preparation now could reduce the impact of a flood if it occurs.

The declaration followed earlier warnings issued by both the City and Borough of Juneau. The Central Council of the Tlingit and Haida Indian Tribes of Alaska also issued warnings. Officials have stressed that the potential for flooding is imminent, and residents are urged to take the threat seriously.

Rising Waters and a History of Devastation

The concern is not without precedent. Suicide Basin has a documented history of glacial outburst floods, including the August 2024 event that caused widespread destruction. That flood damaged homes, disrupted utilities, and left infrastructure in need of urgent repair. It prompted both state and federal disaster declarations.

Experts from the National Weather Service (NWS) and the U.S. Geological Survey (USGS) have been closely monitoring conditions. Their data indicates that the water levels in Suicide Basin have reached or even surpassed those recorded during previous record floods. Icebergs shifting toward the overflow channels suggest that the basin is beginning to overtop. This is a clear sign that the flood could occur at any moment.

“This year’s conditions are particularly concerning,” a joint statement from the NWS and USGS warned. “Flooding is expected to affect the Mendenhall River and surrounding neighborhoods in the Mendenhall Valley.”

Proactive Measures and Community Preparations

Officials are moving quickly to minimize risks. The Alaska State Emergency Operations Center activated to coordinate efforts with local and tribal governments. Actions include interagency cooperation, emergency permitting, public communications, and preparations for protective measures.

City Manager Katie Koester of Juneau stressed the city’s readiness. “We’re not just responding; we’re preparing for every possible scenario,” she said. “The HESCO barriers are in place, and while we hope they perform as intended, this proactive emergency declaration ensures we can act swiftly and decisively.”

Residents are being urged to complete their flood preparations immediately. The NWS estimates that, based on historical patterns, a full outburst event could take up to six days from the point of over-topping. This means that the clock is already ticking.

Public Alerts and Evacuation Plans

Juneau authorities are communicating directly with residents through multiple channels. Authorities used the Wireless Emergency Alert and Emergency Alert System to notify all cell phones in the area after the initial overtop warning. A second alert will follow if the basin begins to release its waters.

Officials are delivering printed notices to homes in the 17-foot inundation zone, instructing residents on evacuation plans and safety measures. Public messaging urges vigilance: “Suicide Basin is full and beginning to overtop. Flood expected. Follow emergency alerts and use the resources provided to stay safe,” reads a prominent warning on the city’s website.

The Human Side of a Looming Disaster

While officials focus on logistical and technical measures, residents are confronting the emotional weight of the situation. Social media in Juneau floods with anxious posts as locals recall last year’s flood. They worry about their homes surviving another round.

“It’s terrifying,” said Marie Jensen, a lifelong resident living near the Mendenhall River. “We’re prepared, but you never really know what will happen until it hits. Last year, the water came so fast—houses were underwater, streets were gone. We can’t afford to be complacent.”

Businesses in the area are scrambling to protect property and stock, while schools and community centers are reviewing emergency protocols. Volunteer groups have mobilized to help with sandbagging, barrier reinforcement, and support for residents who may need to evacuate quickly.