Juneau avoids widespread damage as new flood walls face glacier outburst

A record-breaking glacier outburst flood slammed Alaska’s capital this week. However, for the first time in years, most homes along Juneau’s Mendenhall River were spared.

The water surged out of the suicide basin, a giant pool dammed by the receding Mendenhall Glacier, sending the river to its highest level ever.

New barrier protections

However, two miles of sandbag walls, called Hesco barriers, held back the worst of it. The Army Corps of Engineers installed the walls before the flooding occurred.

In past years, floods have wiped out riverbanks, swept away homes and damaged hundreds more. Officials say that would have been the case again, with nearly 1,000 structures at risk, had it not been for the walls.

“We could have easily had almost 1,000 structures — most of them residences, some multifamily — flooded,” Katie Koester, the Juneau city manager told CBS News. “And for many of those homes, it would have been the second year in a row of flooding. Really cold, icy waters, really difficult to mitigate against, does a lot of damage to your home because of that glacial silt.”

Glacier outburst river surge record

The Wednesday surge caused the Mendenhall River to crest at a record-breaking height of 16.6 feet, according to the National Weather Service. The NWS stated that the height was due to both the surge and the rainfall that occurred days prior to the release.

The river height has already dropped back below 10 feet and will continue to drop throughout the week.

Floodwaters have damaged some roads, trails and bridges so far, but compared to 2023 and 2024, city leaders call it a relief.

“We can all breathe a sigh of relief. For the most part, we had very minimal flooding and avoided a really catastrophic event,” Koester told CBS.

According to the Associated Press, this type of flooding has been an annual concern for Juneau residents since 2011. Officials attribute the flooding to the warming climate, stating that it is causing the Mendenhall Glacier to recede.