Iowa flooding

So what's with all the flooding in Iowa? Why has the state been having so many flooding problems lately? There were floods in 1993 and then again in 2008. Now with record rainfall in 2010, more flooding. Well, there's no doubt that the extra amount of rainfall is the problem, and this could be part of a global climate change. But, what most people don't think about is how much water is normally held in lakes and ponds in northern Iowa. An average size lake can hold anywhere from 200 to 500 million gallons of water. Many of these lakes have silted in over the past 100 years. As these lakes silt in, their average depth decreases. Thus they can not hold as much rainfall as they once did. During heavy rain events these lakes fill up quickly and then overflow into streams and creeks which eventually flow into larger rivers such as the Des Moines River.
Instead of spending millions of dollars on improving dikes and other flood control measures in central and southern Iowa, why not dredge these lakes deeper to hold more water. Many of these glacial lakes were once 10, 12, or 15 ft. deep. Most are now reduced to 5 or 6 ft. Dredging even one of these lakes could allow an extra 500 million gallons to be held in the lake. Once these lakes are dredged they could be kept lower to allow for any heavy rain events. Of course we could just keep the lakes dry or much lower than normal, but this would hurt fish and wildlife populations and eliminate water recreation. Dredging these lakes is the real solution. Not only could this help control flooding problems in Iowa, but also increase the depth and recreational opportunities in these lakes.