Juneau asks Mendenhall Lake evacuation zone residents to leave by 3 p.m.

Unified Command asked residents of roughly 2,000 Mendenhall Valley homes to finish evacuating by 3 p.m. Wednesday, an instruction that reaches an estimated 5,000 people as the Suicide Basin release moves downstream toward a crest early Thursday.

"We're asking folks to finish their evacuation preparations and procedures by 3:00 PM this afternoon," Unified Commander Brian O'Shaughnessy said at a Wednesday morning briefing. Capital Transit will run in the area until 5 p.m. for residents without vehicles, then stop serving evacuation-zone routes.

The National Weather Service issued a flood warning Tuesday afternoon. "We issued the flood warning yesterday afternoon for an expected crest tomorrow morning between 16.1 and 16.6 feet," said Nicole Barron, warning coordination leader at the agency's Juneau forecast office, who put the crest window at 5 to 9 a.m. Thursday. Major flood stage, 14 feet on the lake gauge, is expected to begin after midnight and last roughly eight hours; lower reaches of the river crest an hour to an hour and a half behind the gauge. Barron said the basin has dropped about 25 feet since the release began.

The evacuation request is not enforced, and Unified Command does not know who has left. "We do not have active tracking of who's evacuated or who hasn't evacuated," O'Shaughnessy said, describing accounting for those who stay as a top priority in a breach, work that would take responder time and could delay assistance to others experiencing emergencies.

Officials expressed confidence in the engineered defense while warning that a breach could inundate the area within minutes and leave residents without time to evacuate. "We're tremendously confident in the HESCO barriers ... None of this is worth betting your life. Please evacuate," O'Shaughnessy said. In a failure, he said, "folks would only have minutes before the area could be inundated," with "tens of thousands of cubic feet of water per second" entering a neighborhood where, he noted, many of the homes are only one story. Barron said a barrier breach during major flood stage would trigger a flash flood warning to phones in the evacuation area, carrying an instruction to shelter in place rather than evacuate.

Crews are walking the barriers on foot until the gauge reaches 14 feet, said Denise Koch, operations section chief and director of engineering and public works for the City and Borough of Juneau. All pumps were operational at the time of the briefing, she said. Crews found no damage from a warming fire near barriers in one area, she said, but identified knife slits in the barrier face near Clinton and Vintage, where encampments recur, and are patching them.

Alaska Department of Transportation and Public Facilities Incident Commander Travis Eckhoff said the Back Loop Bridge closes at 8:30 p.m. and Brotherhood Bridge pedestrian paths close around 5:15 p.m. or when the gauge hits 10 feet. The U.S. Forest Service said the Mendenhall Glacier Visitor Center will close around 4 p.m., with the west side of the lake already closed and the entire recreation area closed to visitors by evening.

The American Red Cross shelter at Floyd Dryden gym housed a family of six overnight, said Loren Joseph of the Red Cross. It carries supplies for 50 and holds about 75. The shelter also has an area for cats and dogs, kept separate from their owners, with volunteers from the Juneau group Grateful Dogs caring for them. The flood information hotline is 907-500-0890, and residents can sign up for emergency alerts by texting CVJ to 38276.

Juneau's outburst floods from Suicide Basin recur each summer as glacier melt fills and releases the basin, a pattern that has pushed officials to revise evacuation maps, routes and shelter plans with each cycle rather than treat any single release as an isolated emergency.