Hesco Barrier Phase 1
Latest Updates
03/21/2025: CBJ encourages riverfront property owners in the HESCO barrier project area to research their property’s drainage system to identify the inlet and outlet to all drainpipes. CBJ released an FAQ document with guidance on this topic.
03/19/2025: Contractors began site and access preparation for the HESCO barrier installation at several locations along the barrier alignment. Please watch for construction equipment and personnel and obey construction traffic control signage.
03/03/2025: The LID ordinance (link) is now in effect. CBJ project managers and contractors are conducting site visits at homes where barriers will be installed. HESCO barriers and flood fighting materials are in transit to Juneau. The Assembly approved the “Notice to Property Owners and MOU” (View Memo and meeting materials).
See “Timeline & Status” below for additional updates.
Project Background
The Mendenhall River Valley in Juneau, Alaska is under imminent threat of unusual flooding from what scientific experts expect will be recurring and likely record-breaking glacier lake outburst flood (GLOF) events. 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.
CBJ is working tirelessly with Federal, Tribal, State and local partners to gather the additional information and resources needed to identify and implement a long-term solution. However, a long-term solution will take years before it can be implemented due to the unusual source and nature of the flooding and the complex hydraulics and engineering required.
Therefore, emergency mitigation and immediate flood resilience action is needed to protect the most vulnerable in our community before the 2025 GLOF season.
With extensive consultation and involvement from United States Army Corps of Engineers (USACE) flood fighting experts, CBJ plans to install USACE provided HESCO barriers as a near-term solution to mitigate potential widespread damage from future releases. Based upon factors such as the high-water marks obtained after the 2024 GLOF and the resources available to implement a solution before July 2025, a 2 mile stretch of riverbank was identified which would provide the most protection to the highest number of flood-vulnerable residents and homeowners. This is considered Phase 1 of CBJ’s formal flood mitigation efforts. This interim solution is intended to protect against GLOFs that are up to 20 ft high, or 4 feet higher than the 2024 GLOF event. CBJ will integrate the work of a comprehensive hydrological and hydraulic analysis to implement Phase 1 in a manner to avoid downstream impacts.
Contact Us
- To comment, provide input, or for general project inquiries, please email [email protected].
- Visit juneau.org/manager/flood-response for more information on CBJ’s ongoing flood response efforts.