In 2008 –statewide -- nine Iowa rivers crested at record levels. Damages ranged from the flooding of more than a dozen buildings at the University of Iowa in Iowa City ... to an estimated devastation of 1.2 million acres of corn and soybeans ... to the loss of more than 4,000 hogs.

With floods and tornados, 85 of the state's 99 counties were declared Presidential Disaster Areas. The Rebuild Iowa Office says nearly 40,000 Iowans registered with FEMA for disaster assistance. Federal and state disaster aid promised stands at more than $2 billion.

All that damage … and the state didn't even receive record rainfall.

Larry Weber, Director,IIHR Hydroscience & Engineering, University of Iowa, Iowa City: "The rainfall itself was not of epic proportion and was really consistent with other rainfall years than we've had in Iowa. What was quite different last year was the flooding was of epic proportion."

Basically, Weber says, timing is everything. The distribution of rainfall on already saturated land, ran off, into rivers and streams. In addition to rainfall, there were other factors involved, says a Research Geologist who studies Iowa's annual stream flows.

Keith Schilling, Research Geologist, Iowa DNR, Geological and Water Survey: "We've seen 30 – 40 percent increase in stream flow that completely overwhelms how much extra rain there has been. And so the increase in stream flow is more than what increase in precip alone can account for. And then we start having to look at other factors that might be contributing to that and then that's where we get into issues like land cover changes."