The Gazette covers City Hall, now a flood-damaged icon on May's Island in the Cedar River

City officials say temporary, multimillion-dollar flood protection systems they purchased did yeoman’s duty on the Red River of the North

In City Hall, Floods, Jim Prosser on April 1, 2009 at 4:54 pm

Two Cedar Rapids city staffers have trekked to Fargo, N.D., and Moorhead, Minn., to see how those cities’ temporary flood-protection systems stood up against the Red River of the North.

The systems included the use of Hesco wire baskets that are filled with sand and rubber bladders filled with water, both of which the city of Cedar Rapids has purchased for temporary flood protection.

In an discussion Wednesday with The Gazette’s editorial staff, Dave Elgin, the city’s public works director, and Craig Hanson, the city’s public works maintenance manager, said they are satisfied with how the two systems worked up north and are satisfied the city made the right purchase for temporary flood protection for Cedar Rapids.

Elgin put the price tag on the city’s purchase at about $5 million, a purchase that includes additional pumps to protect the city up to a flood level of 24 feet. That level is two additional feet above what the city’s flood-action plan can protect today and four feet above what had been the city’s historic flood level. But it is seven feet lower than the level of the 2008 record flood here. Providing for temporary at the level could cost $360 million, the city officials estimated.

Hanson noted that both the Hesco baskets and the rubber bladders had their surprises in Fargo and Moorhead, but those are surprises that aren’t likely to happen here.

For instance, the water in the bladders froze up north, and frozen water floats, Hanson noted. Flooding in Cedar Rapids doesn’t usually include freezing temperatures.

Hanson noted, too, that the Hesco baskets may have tipped a bit up north in certain spots as the ground underneath them got muddy. The plan in Cedar Rapids, he said, it to place the Hesco defense on sidewalks and streets if possible.

The city intends to use the Hescos to protect both sides of the river through the downtown and at Czech Village and to use the water-filled bladders in the Time Check area.

Elgin noted that the Red River up north drains a watershed much, much larger and flatter than the Cedar River that runs through Cedar Rapids. As a result, cities along the Red River have more time to prepare for flooding because the river rises more slowly.

Here, the city has two to three days to prepare for a flood, Elgin said.

Elgin, Hanson and City Manager Jim Prosser stressed that a temporary system of flood protection has a lot of moving parts as a city deals with flood water, rain water behind the temporary protection and water filling sewers with no place to go.

“It’s more than just putting up barriers,” Prosser said.

Temporary protection, he said, will never do what the city’s proposed permanent system of levees and flood walls will be able to do.

At the same time, Prosser noted that the city’s current flood-action plan has worked well in recent years, at least until the June 2008 record flood.

Elgin pointed out that action plan easily handled a flood crest of 17.1 feet last April without anyone here really noticing.

Elgin and Hanson talked about ice jams on the river here and how that can prompt early season flooding. A newly installed sewer shut-off value at Penn Avenue and Ellis Boulevard will prevent water from backing up into the storm sewer there in the event of ice dams, Hanson said.

No, Elgin added, he didn’t think the city would institute a blasting program to break up ice as they do in North Dakota.

The city already has received its purchase of water-filled bladders, called tiger dams. It’s shipment of Hescos will arrive in about a month, Hanson said. The Hescos had been expected last week, but the city diverted its shipment for use in Fargo.

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