Residents Hopeful Amid Revised, Lower Flood Forecast

Mendenhall River Flooding: Residents Brace as Waters Rise

Juneau residents living along the Mendenhall River are managing a glacial outburst flood that began cresting Thursday morning, Aug. 13, 2026. While the water levels are rising more slowly than initial projections, residents in the Mendenhall Valley are balancing caution with relief as recent infrastructure upgrades, including HESCO barriers, face their latest test. According to KTOO, the National Weather Service in Juneau forecasted the flood to crest between 8 a.m. and noon on Thursday.

Infrastructure Performance and Resident Preparedness

The current flood response utilizes HESCO barriers, which were installed following the 2024 event that saw nearly 300 homes flooded. Last year, approximately 50 homes were inundated after those same barriers experienced leaks. As of 10:20 a.m. Thursday, water had not yet touched the barriers along Marion Drive and Meander Way, according to KTOO.

For some, structural reinforcements have provided a sense of security. Resident Sam Hatch, who lives on Meander Way, noted that his family raised their home on steel pilings 30 feet deep in 2024. Despite his confidence in his reinforced home, Hatch acknowledged the persistent risk of the water table rising through the gravel foundation of the neighborhood. “The ultimate nightmare fuel is the barriers letting loose,” Hatch told KTOO, though he noted the current barriers appear “bigger, they are heavier, they are thicker and more tied together” than previous iterations.

Emergency Response and Local Incidents

City officials managing the response had recommended that residents evacuate the area by 3 p.m. on Wednesday, Aug. 12, to ensure safety for both the public and first responders. Ryan O’Shaughnessy, the city’s emergency programs manager, emphasized during a news conference that evacuating was the most effective way to maintain safety during the event, as reported by KTOO.

The flood event also impacted local aviation. According to reports from Newslocker, an Alaska Seaplanes de Havilland Beaver aircraft made an emergency landing in the Mendenhall River around 11:17 a.m. on Thursday. The plane had just departed from the float plane pond at Juneau International Airport. No injuries were reported, and officials confirmed there was only one pilot on board.

Comparing Flood Impact Trends

The current event demonstrates a shift in both the intensity of the flooding and the community’s ability to manage it. Data from KTOO highlights the following progression of impact on residential properties in the Mendenhall Valley:

• 2024 Event: Nearly 300 homes flooded prior to the installation of HESCO barriers.
• 2025 Event: Approximately 50 homes flooded after the HESCO barriers experienced leakage.
• 2026 Event: Residents report a slower rise in water levels compared to initial predictions, with many opting to stay in their homes or monitor the situation from nearby locations.

Frequently Asked Questions

What is the cause of the flooding in the Mendenhall Valley?
The flooding is caused by a glacial outburst, where water trapped by a glacier releases suddenly, causing the Mendenhall River to swell rapidly, according to KTOO.

Are residents still being asked to evacuate?
City emergency officials issued a recommendation for residents within the flood zone to evacuate by 3 p.m. on Wednesday, Aug. 12, ahead of the anticipated crest on Thursday, KTOO reported.

What infrastructure is in place to protect homes?
The city has deployed HESCO flood barriers, which are designed to hold back rising waters. Some residents have also independently raised their homes on steel pilings to mitigate damage from annual flood events.

Stay informed on the latest developments by following local emergency updates and the KTOO live blog. Have questions about flood preparedness in your area? Share your thoughts in the comments below or subscribe to our newsletter for ongoing coverage of Juneau’s infrastructure and environmental news.