Two months ago Cedar Rapids had another flood. The Cedar River overflowed and now the citizens of Cedar Rapids are repairing the damage. Many Iowans compare this occurrence with the larger Flood of 2008 in which both the Cedar and Iowa Rivers overflowed and caused what FEMA estimated to be almost 800 million dollars in damage.
It got me to thinking. How do the Iowans (or anyone) truly predict a flood? Sitting here in Brooklyn, I had always thought that you predict a flood from the intensity of the rainfall. Around here if the rain falls hard and nonstop for a few days, it is only natural that the result will be water rushing over the curb, onto the sidewalk and maybe over the surface of the street.
Predicting a real flood is more complicated than that. One must take the river into account as well.
I found a posting in Decorahnews.com dated April 5th 2015 which provided some insight. A study was being conducted in the Upper Iowa River Basin by Luther College Professor Richard Bernatz and some members of the Iowa Flood Center. Why the Upper Iowa River? One reason is that area is one of the originating spots of the 2008 Flood. They have already established a series of rain gauges throughout the district – and by setting the study here, they are able to measure river flow calculations with rainfall data. By putting them together, they are able to observe flood potential of the river with added water from the rain. They published their findings in The Journal Of The Iowa Academy Of Sciences Vol 118 Issue 104. Of course, this is still in the research/observation stage, but when a wall of water is heading your way, any research is a most welcome and helpful step.