Midwest Flooding

Reading about the current flooding going on in the Midwest has brought back memories of our experience with the aftermath of the Great Flood of 1993. I find it kinda tough to read just because after those floods 15 years ago, there were so many recommendations and lessons to be learned that much of the devastation going on would have been avoided or at least expected.

Specifically I am talking about those areas in the river valleys. In 1993 we learned that the Army Corps of engineers had created a survey laying out the elevation that both the 100 year and 500 year flood would reach. The 100 year flood being a flood that would occur once every 100 years. Likewise for the 500 year flood. The floods in 1993 had about reached the 500 year flood mark and if memory serves correctly a 100 year flood had occured about a decade or two earlier. One of the recommendations or at least requirements made by FEMA was that those who were receiving aid for damage from the 1993 flood will not receive aid for future floods for any damage incurred below the 500 year flood mark. In other words, if you build below that line, you do so at your own risk.

One reason these 100 and 500 year floods are occuring with more frequency is due to the levees. Before these river valleys had become populated and were farmed due to the fertility of the river valley plain, the river would regularly overflow it’s banks. It kept the wetlands replenished and added sediment and nutrients to land that the farms now take advantage of. In order to protect the crops along with cities that have grown next to the rivers, levees were created to keep the flood waters out. The problem is that this has channelized the river leaving no where for the water to go except up. And as the water goes up, so do the levees. At some point, the levees have to give with all that accumulated water piling into the new space. So places that would have not been flooded otherwise are now under water.

What I remember from our time visiting the flooded areas in 1993 was that the property in the river valley was cheap due to the risk of flooding. The people who lived there are of meager means who likely could not afford to live elsewhere. Not necessarily people who can afford that kind of risk.

So it’s tough to hear that the people of the area are going through it again. They were told the previous flood was once in lifetime and although it was recommended to raise their residences, they didn’t have the means to take those measures. Or their place is now under water since pressure created by a levee able to stand it’s ground weakened their levee to failure.

But what exactly can be done. Do you just suggest that the residents live with their lot? Be better prepared for the next one? Give up fertile farmland that they can afford? Ask them to just deal with the possibility that they’ll completely lose a crop every decade or so? Tell them just to move out of there, someplace they may have called home all their life, in order to return the land to wetlands?

Our proposal for the city we studied was to relinquish those structures that were below the 500 year flood elevation and raise the waterfront to above that level. But seeing as how that elevation no longer seems realistic, would that just have to be done again in the next decade or two? At the time, it seemed like the easy answer, but the second time around it doesn’t look all that simple.

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~ by Frank on June 20, 2008.

One Response to “Midwest Flooding”

  1. […] people in society. Since flood plains carry the risk of occasional floods, the land is cheaper and attracts people who can’t afford other locations. So it was hard to enter the homes back then and see black mold already forming and thick up to 4 […]

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