Juneau officials urge residents in expanded advisory to prepare to evacuate ahead of predicted 2026 glacial flood

Juneau City and Borough officials and federal and tribal partners on July 9 urged residents in an expanded evacuation advisory to prepare to evacuate during a predicted 2026 glacial lake outburst flood and described how temporary barriers, pumps and new monitoring tools will be used to protect the city.

City Manager Katie Koester said the briefing’s primary message was simple: residents in the advisory area should evacuate during the event to protect life and make it easier for first responders to operate. Koester noted the scale of this year’s response: “we’ve been working very hard on that, and we will have a really robust update at the July 20th Special Committee of the Whole,” and said roughly $45,000,000 in protective infrastructure has been brought to bear this year.

The advisory covers just over 1,900 residences, CBJ emergency programs manager Ryan O’Shaughnessy said, up from about 1,000 last year. He described a shift from inundation‑only maps to street‑aligned evacuation maps intended to capture areas where access or emergency response could be compromised. “If we can’t get to you during a breach scenario, or if you may not be able to get to safety, we are recommending that you evacuate,” O’Shaughnessy said.

Officials emphasized the advisory is not a local mandatory evacuation order. O’Shaughnessy explained that Alaska law gives the governor authority to compel evacuations but does not provide that authority to local governments: “Alaska statute, title 26, chapter 23, grants very specific evacuation authorities to the governor’s office ... It does not provide the same language or authority to local governments.”

How residents will be notified: the unified command will use multiple channels, O’Shaughnessy said, including wireless emergency alerts (WEA), the Emergency Alert System, door‑hanger notifications in the evacuation area and opt‑in alerts via AlertSense. Officials plan a live WEA test next Thursday at 3:30 p.m. and asked residents to sign up for CBJ alerts and review evacuation maps on the Juneau Flood Ready page at juneau.gov.

Operations and logistics: the Army Corps and CBJ have deployed temporary HESCO flood barriers and are placing pumps to manage seepage and collected water behind the barriers. City chief engineer John Bohan said large pumps provided by the Army Corps will begin deployment next week and will pump water across the barriers back into the river; he warned residents not to tamper with equipment and said a pump deployment map will be posted on the city website. Capital City Fire & Rescue Chief Tom Hatley described staffing and staging plans, including boat teams on both sides of the river and temporary relocation of some station personnel to maintain response capacity if bridges are impacted.

Transportation and airspace: Alaska DOT&PF said Back Loop Bridge will be closed to vehicles and pedestrians if lake gauge reaches 12 feet and will remain closed until inspections confirm safe operation; Brotherhood Bridge will remain open to vehicles but pedestrian access on portions of the bridge and adjacent pedestrian paths will be closed during the flood. DOT also said it will issue a temporary flight restriction (TFR) to allow drone operators to monitor barrier performance and river conditions during the event.

Shelters and volunteer support: the Red Cross will host an emergency evacuation shelter at the Floyd Dryden former middle school, and the city will coordinate with faith communities to stage parking and vehicle staging outside the flood zone. Officials confirmed sandbag distribution events beginning Saturday, July 11, and continuing weekly until the event; volunteers are welcome.

Why officials urged evacuation: speakers repeatedly described the HESCO barriers as temporary, sandbag‑like measures that can perform well but remain vulnerable to tree strikes and other failures during a dynamic event. “These are resilient structures,” John Bohan said, “but ... they are still temporary measures.” Officials said evacuation keeps residents and first responders out of harm’s way.

What comes next: CBJ and partners will continue public updates via the Juneau Flood Ready page and through alert channels; the unified command will refine messaging as monitoring data arrives. Those with non‑emergency questions were directed to the city’s central flood email (floodresponse@juneau.gov) and to resources posted at juneau.gov.

Ending: Officials closed by reiterating the core message — heed evacuation advisories and sign up for alerts — and reminding the public of the weekend Diamond Park outreach event for sandbagging instruction and pump map review.