Contractors in Juneau have installed two miles of glacial flood barriers to prevent another devastating summer flood. The temporary barriers stretch along the Mendenhall River, where floodwaters damaged nearly 300 homes last year.
Over the past two summers, water from the Suicide Basin has surged downstream, smashing into homes without warning. Last year’s Jökulhlaup flooded nearly 300 homes after 16 billion gallons spilled from the basin.
The year before, entire homes were swept away by rapidly rising water. The source of the flooding was the Suicide Basin, which was once covered by glacial ice. Due to warming temperatures, it fills each year with meltwater and rain.
That water eventually forces its way beneath the Mendenhall Glacier and rushes into the lake and river below. This summer, workers from Coogan Construction quickly installed flood barriers near homes, schools, and backyards, some stacked 8 feet high.
They are large reinforced containers filled with dirt designed to act like levees. Juneau Deputy City Manager Robert Barr said the temporary barriers were the fastest option available and had a ten-year design life.
The project’s price tag is $7.8 million. Homeowners in flood zones will cover 40% of that, with the rest paid by local ratepayers. But not everyone is convinced this will be enough. Aaron Jacobs from the National Weather Service warns that no one knows how much water Suicide Basin can hold.
A sudden warning or heavy rain could make the next flood even worse. Meanwhile, a $10 million federal study hopes to find a permanent fix, though early estimates put that cost in the hundreds of millions.
