Sealaska Fortifies Mendenhall River Against Glacial Floods

A 60-person team completed the work on July 3, finishing 12 days ahead of their contractual deadline. The operation involved securing four miles of the river corridor, where crews installed 14,110 linear feet of HESCO flood barriers and placed 112,872 tons of rock armoring. At the height of construction, logistics teams managed the placement of 1,630 tons of material daily, including the assembly of a 1,100-foot-long, 12-foot-high levee built with locally sourced fill from the Montana Creek pit.

This infrastructure upgrade arrives after two consecutive years of record-breaking flooding that devastated the region. In 2024 alone, glacial surges damaged nearly 300 homes, following a 2023 season that forced an emergency declaration from city officials. Beyond the physical barriers, the project emphasized local impact, with Alaska Native employees comprising 25% of the skilled workforce. While these measures provide an immediate defense, the U.S. Army Corps of Engineers continues to evaluate long-term strategies for the recurring glacial threat.