City declares flood threat over, but assessments, cleanup and repairs will take some time

Officials ask non-residents to avoid flood zone neighborhoods due to debris cleanup, riverbanks due to instability and Back Loop Bridge due to damage

The Back Loop Bridge is closed indefinitely due to damage sustained from a tree strike during a glacial lake outburst flood that crested Aug. 13, 2025. (Photo by Kevin Henderson)

By Mark Sabbatini

Juneau Independent

Another record glacial lake outburst flood has subsided — this time without the widespread damage to homes that occurred the past two years — but plenty of short- and longer-term work again remains to be done.

An alert issued by the City and Borough of Juneau shortly after 3 p.m. Wednesday stated "the flood threat from Suicide Basin has ended and waters have receded." However, the notice states neighborhoods under an evacuation advisory during the threat were intended to be opened only to people living in those areas.

"Crews will be moving through affected areas to assess damage and other impacts," the notice adds. "Please continue to use caution around damaged areas and avoid riverbanks. Do not drive through standing water. In addition to posing a safety hazard, driving generates waves that cause additional damage to nearby structures."

Information about debris disposal and other post-flood recovery will be posted at bit.ly/JuneauFloodRecovery, according to CBJ. The Flood Information Hotline at (907) 500-0890 is also available for non-emergency questions. People interested in volunteering help or seeking help from a volunteer can contact www.unitedwayseak.org/2025-flood-relief.

This year’s flood, which apparently began Monday night and was detected at about 9:20 a.m. Tuesday, resulted in the Mendenhall River reaching a peak crest of 16.65 feet at about 7:15 a.m., according to the National Weather Service Juneau. That is 0.66 feet higher than the previous record set last year, which itself was about a foot higher than what was a record flood in 2023.

Nearly 300 homes were damaged last year, but this year a two-mile semipermanent levee of HESCO barriers were placed along a stretch of the Mendenhall River. While officials and residents said the barriers largely provided the protection expected, seepage occurred in some spots and a tree strike ripped a hole in the barriers behind the Dimond Park Field House.

Concern about further problems due to trees being swept away was expressed by the weather service in a social media post at about 12:30 p.m.

"We have received reports that as the water recedes, the bank is unstable and is allowing trees to fall into the river," the post states. "This is a reminder to stay away from the river and allow officials to do what they need to do."

Mariners are being advised to watch for trees and other debris in Auke Bay and other waters near Juneau.

Significant damage also occurred to the Back Loop Bridge, which is closed indefinitely, according to the Alaska State Department of Transportation and Public Facilities.

"(The bridge) has sustained erosion damage to one of its downstream abutments," DOT noted in a statement published shortly after 1 p.m. Wednesday. "The back end of the bridge is undermined, and water is still flowing and eroding the structure. There are also active hazards in the water in this area. The bridge is off limits to all motorists, pedestrians, and cyclists. Do not attempt to cross the bridge."

The closure extends from Mint Way to Montana Creek Road, although both of those streets remain accessible, according to DOT.

"DOT&PF bridge engineers are conducting inspections and monitoring to determine necessary repairs," the statement notes. "Materials have been delivered to mitigate erosion, but more work is needed. We will provide updates when inspections are complete and a repair timeline is available once water levels lower."

The Kaxdigoowu Heen Dei (Mendenhall River Trail) and Kax Bridge are also closed until further notice for inspection and assessment of damage, according to CBJ.

GCI issued a notice at about 1 p.m. that some of its equipment had temporarily lost power.

"Some customers with GCI mobile and internet may be unable to use services, including some business services in the Juneau community," the company’s notice states. "GCI crews are coordinating with response teams and local utilities to make repairs when it's safe to do so. We will post updates as more details become available."

The Juneau Assembly has scheduled a special meeting at noon Friday to consider a resolution declaring a local emergency, and seeking state and federal assistance. The Assembly and Gov. Mike Dunleavy issued preemptive local and state disaster declarations, respectively, intended to speed action on assistance requests following the flood.

All Juneau public schools will be closed on Thursday, which would have been the first day of school for elementary, middle and high school students. Juneau School District Superintendent Frank Hauser said school will now start on Friday, subject to change depending on the situation.

• Contact Mark Sabbatini at editor@juneauindependent.com or (907) 957-2306.