Barrier work for Mendenhall Glacial Outburst Flood project is 45% completed

Published 4:30 am Tuesday, May 5, 2026

Barrier installations for the Mendenhall Glacial Outburst Flood project is 45% complete as of April 29, the Alaska District of the U.S. Army Corps of Engineers says.

Crews have been working on Phase 2 of the Advance Measures Mendenhall Glacial Outburst Flood project. Last week, they began armoring work at Reach One South.

U.S. Army Corps of Engineers, the City and Borough of Juneau and the Forest Service determined that a flood barrier berm north of Reach One was feasible and began planning. Barrier construction will continue at Reaches Three and Six in May.

The fortified, complete temporary flood barrier needs to be completed prior to July 15. It is a near-term solution to mitigate potential widespread damage from future flooding events.

Phase 2 is a flood barrier that includes:

• The continuation of barriers from the end of Phase 1, down river on the east bank through the Brotherhood Bridge

• The west bank of the river north from Brotherhood bridge, along the Kaxdigoowu Heen Dei (trail) to higher ground above the Wildmeadow Lane neighborhood

• The west bank from Back Loop Bridge extending downstream through the extents of the River Road neighborhood

• The east bank from the Back Loop Bridge, extending downstream to connect to the beginning of Phase 1 at the north end of Marion Drive

On Sept. 19, 2025, the CBJ submitted a scope of work that the United States Army Corps of Engineers accepted to include – but not limited to – the ongoing evaluation, repair, and reinforcement of existing HESCO barriers and barrier sites, paid for with 100% federal funds.

The Mendenhall River Valley is under imminent threat of “unusual flooding from what scientific experts expect will be recurring and likely record-breaking glacier lake outburst flood events,” according to the project background on the CBJ website.

“The impact and inundation area of these events have increased each of the last three years; a pattern that puts hundreds of homes and thousands of vulnerable residents, as well as critical infrastructure, public facilities, and community and medical services at risk.”