With recent flood-prevention efforts on the Iowa River, it seems this may become an annual ordeal.
Now, the Iowa City City Council will rev up conversations to proceed with river restoration and future flood mitigation plans. The council will discuss during tonight’s work session.
Specifically, city officials will present plans for a potential new whitewater-rafting course just south of the Burlington Street Bridge, in the Riverfront Crossings District, following dam modifications.
The proposed changes, in addition to pending plans to demolish the now defunct North Wastewater Treatment Plant, 1000 S. Clinton St., will bring a new large-scale recreation area that will also help mitigate future flooding.
“We want this to be a passive park and active park,” said Steve Long, the Iowa City community-development coordinator.
The park will be an open space for everyone to enjoy along with picnic space, Long said, and he hopes the river will be suitable for whitewater activity.
It is estimated that the project will cost $530,140, and the city will be responsible for $169,000. The rest is covered through outside grant funding.
Iowa City recently received $8.5 million in grant funding to remove the waste-treatment facility and redevelop parkland in the Riverfront Crossings District.
If the proposal is passed by the City Council, Denver-based McLaughlin Whitewater Design Group will evaluate the area to determine which specific adventure activities can be implemented in the area.
Long said community-development officials are looking at potential mountain bike trails or zip lines across sections of the river.
Citing the death of five people as a result of going over the dam since the 1960s, Long said the current dam in place is too unsafe for recreational access.
However, proposed modifications to the dam would make a multi-mile stretch along the river safe for water passage, he said.
Additionally, Long said that demolishing the North Plant will bring down the ground level to the floodplain, which will absorb rising water.
Iowa City Public Works Director Rick Fosse said his department will be responsible for the demolition of the building, but Long’s department will begin the recreational redevelopment.
The Public Works Department will also present a comprehensive plan before the City Council in further efforts to help with future flood mitigation.
Fosse said that Iowa City’s overall strategy is to combine the demolition of the waste-treatment facility objective alongside buyout and Gateway Project objectives. The goal is to accommodate flood flow.
The Coralville Dam is responsible for most of the flood mitigation.
“There are not a lot of people pausing to appreciate that,” Fosse said.
He said that during the flood of 2008, the dam reduced 40 percent of potential flooding in the local area.
The peak experience would have been 33,000 cubic feet per second as opposed to the recorded 19,200, Fosse said.
The city’s job now is to make sure that as much of the exposed land along the Iowa River after the reservoir dam is within the 100-year floodplain, he said.
Creating vast amounts of green-space along the river and zoning to make sure that people cannot build in floodways are smart ways for Iowa communities to prevent future flooding, said Lori McDaniel of the Floodplain and Dam Sector of Iowa Department of Natural Resources.
There is a 1 percent chance of flooding per year within the 100-year floodplain, she said. However, when attached to a plot of land with a 25- or 30-year mortgage, then there is a 25 percent that serious flooding could occur.
“We could have outdoor education and classrooms with a lot of opportunities,” Long said. “People can learn about Iowa wetlands from school age to university age and on.”