Friday, June 13, 2008

Rising Midwest rivers force evacuations, expose vulnerable dams and levees

Residents blaming the worst flooding in the Midwest in some 15 years on aging and weak infrastructure that seem barely able — or in many cases unable — to hold back the waters

Colin Taylor watches the swollen Cedar River as it nearly reaches the underside of a bridge in downtown Cedar Rapids, Iowa. (Tribune photo by E. Jason Wambsgans / June 11, 2008)
CEDAR RAPIDS, Iowa – With rumbling force, the Cedar River on Wednesday ripped through this eastern Iowa city toward a historic crest while unleashing floodwaters into businesses and homes.

With thunderstorms looming, thousands of residents quickly evacuated the downtown area as state officials warned the levee barely holding back the river could burst overnight and inundate city streets with water for miles around.

Churning currents licked at the city's bridges closed to traffic by nightfall and in danger of its footings being crippled.

The worst flooding in the Midwest in some 15 years has exposed the vulnerability of aging and weak dams, levees and bridges that seem barely able — or in many cases unable — to hold back floodwaters.

Spectacular breakdowns were seen this week in Indiana, Illinois, Iowa and Wisconsin leaving questions as to whether the region is prepared to handle such a disaster.

Up the Cedar River in Washburn, Iowa, Joann Vanee's farm was an island Wednesday after mom 'n' pop dikes failed to contain floodwaters.

Built by local residents to keep the river at bay at a 19-foot height, the walls were overrun by some five feet and turned acre after acre of choice agriculture land into a sea of misery.

"There's nothing you can do when you get that much water," said Vanee, whose farm was accessible only by a rescue boat that brought out a generator so she could pump her basement. "It's just too much."

In southeastern Illinois, residents in Lawrenceville saw homes submerged after a levee breached on the Embarras River on Tuesday. The water turned farmland into lakes.

Officials in Wisconsin, where heavy rains loom, were warily monitoring dams that were filled to the brink and spilling over. The state was still trying to figure out how a wall of earth crumbled, leading Lake Delton to empty out and become nearly bone day.

While state officials place much blame on last weekend's torrential rains that dumped in excess of 12 inches of water, some residents say the lake was vulnerable because of weakened walls and dams.

Don Kubenik, whose $1.3 million vacation home was cut in half by raging lake waters, says officials should have known that the collapsed wall and roadway above it was structurally deficient. Nor did officials act quickly enough to release some lake water through the lake's main dam, he said.

"We thought everything was done to make sure the lake was safe and now we find out that it was a time bomb," he said. "I built on high ground thinking this could never happen and now I have no ground."

The severity and frequency of flooding in the Midwest has alarmed flood plain managers and others who monitor the effects of raging water on the public infrastructure.

A December report from the Association of State Floodplain Managers warned that "millions of citizens and hundreds of communities neither recognize their flood risk nor accept responsibility for reducing that risk."

Experts say the increasing frequency of severe storms and flooding is undermining the integrity of aging levees, bridges and dams that were not designed to withstand the water flow and pressure that contributed to destruction like that seen at Lake Delton.

Barry Drazkowski, director of GeoSpatial Services at St. Mary's University in Winona, Minn., said the idea of "normal" heavy rainfall is changing.

"If we look over the past 100 years, it is not normal to get so many large amounts of rain like those we've seen in such a short period of time," he said.

"This is going to start to affect a lot of our river cities that are protected by levees [that] don't assume 15 inches of rain at a time," Drazkowski said. "As these events become more frequent, all of a sudden that 100-year protection might become 50 years and communities won't be as protected as they originally were."

Officials in several Iowa communities closed bridges earlier this week as high water crept closer to road levels. That takes a structural toll on bridges, many of which were built decades ago.

"We're dealing with a lot of bridges built in the last 80 to 100 years and they weren't designed for today's standards," said Larry Larson, executive director of the flood plain managers group in Madison, Wis.

At a flood policy forum last fall in Washington, D.C., officials warned that the combination of climate change, dramatic population increases and the destruction of natural ecological protections, such as wetlands, will add to the already existing strain on aging infrastructure.

"We as a nation have ignored our infrastructure for the past 50 years. We haven't gone back to maintain the old roads and bridges and we just keep building new ones," Larson said. "We've given up the public safety of existing structures in the name of economic development."

Even before the recent flooding, federal officials were wary of aging levees. Amid blistering public condemnation following the failure of levees during Hurricane Katrina, the U.S. Army Corps of Engineers moved to evaluate some 2,000 levees under its purview.

On the Illinois side of the Mississippi River, officials in metro St. Louis were stunned to learn last summer that its levee that stretches 83 miles south from Alton was suffering from underground seepage and rusting mechanics.

More than 175,000 residents and business with some 50,000 jobs are in danger if the levees fail. Officials also fear environmental disaster because a major refinery and oil transmission pipelines are just yards from the levees.

Acting quickly, local officials decided to levy a quarter cent sales tax to pay for a share of the $180 million needed for upgrades. Work is set to begin this summer.

But with raging waters from the Upper Midwest set to dump into the Mississippi in the coming days, the river could rise past levels seen during the last major flood in 1993.

"The question is why didn't they keep those levees up to par?" Wood River resident Helen Crause asked last week. "If that levee goes, we'd all be underwater and contaminated by the mix of water and oil. That's a terrifying thought."

E. A. Torriero reported from Iowa and Tim Jones from Chicago.

etorriero@tribune.com

tmjones@tribune.com

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