Dave Olson, Published January 09 2011
Removable floodwalls waiting on parts
But structures now in place on Moorhead’s First Avenue North near the Horn Park neighborhood of south Moorhead can be quickly transformed into flood barriers when the need arises, said Assistant City Engineer Tom Trowbridge.
The two removable floodwalls are part of numerous flood-mitigation projects the city embarked on following the 2009 flood.
The floodwall at First Avenue North, which will extend about 65 feet across the avenue when assembled, cost approximately $650,000.
Much of the expense was due to the extensive foundations required, Trowbridge said.
The removable floodwall in the area of Dale Avenue and Third Street South is about 20 feet shorter and cost about $300,000.
Trowbridge said the latter was also less expensive because it was bid as part of a larger floodwall project and economies of scale came into play.
Money for both projects came from the Minnesota Department of Natural Resources.
Trowbridge said aluminum planks with watertight gaskets will be stacked together to form the removable floodwalls.
Right now, those are on order from Europe, but it is expected they will arrive before any spring flooding, Trowbridge said.
He said the First Avenue North floodwall, in conjunction with a series of permanent and temporary dikes, will protect the Hjemkomst Center and nearby housing complexes to a river stage of 44 feet.
During heavy flooding, water from the Red River collects in the First Avenue North railroad underpass and flows west on First Avenue toward the Hjemkomst Center.
With the protections in place, vehicles will still be able to reach First Avenue North – as well as the Hjemkomst Center and nearby properties – via a special driveway the city built near the foundation of the removable floodwall.
The protective structures have Maureen Kelly Jonason, executive director of the Historical and Cultural Society of Clay County, feeling better about potential spring flooding.
Jonason said that during the 2009 flood, the society had to close its museum, which is in the lower level of the Hjemkomst Center, for 30 days.
“That was a huge, huge blow,” she said.
Trowbridge said the removable floodwall located in south Moorhead, where Third Street meets Brook Avenue under Interstate 94, has long been a problem area during floods.
“We’ve had to build a dike there every time. That will be a real nice floodwall for us to have,” he said.
Readers can reach Forum reporter Dave Olson at (701) 241-5555