... Versus Nature
Outside of the Midwest, not enough attention has been paid to this month's flooding in Iowa. But Iowa produces more corn and soybeans than any other state and the United States and the rest of the world depend upon the farms there for so much of its food. The crop damage alone there could reach $3 billion.
The Midwest got a lot of rain this spring, most of it falling upon ground that was already saturated. It was also a cooler than normal spring, so many farmers delayed planting their crops. The region was going to see some flooding no matter what. But decisions made by men turned a natural disaster into a man-made one.
Start with the farmers. With corn at an all-time high, more than a third of Iowa's land surface is covered with that crop. Corn's shallow root system doesn't soak up water as well as the deep-rooted prairie grasses that used to cover the land. Crop rotation has also fallen out of favor, with many farmers sticking to corn or soybeans year after year.
Many farms also use drainage systems to lower the water table and keep water from pooling in fields. This means water moves more quickly from cornfields to steams and rivers. Those waterways are increasingly filled with sediment from field runoff, reducing their capacity.
One would think that after the devastation of the 1993 floods, Iowans would think twice before building in a flood plain. But after two of what the National Weather Service calls "500-year floods" in the space of 15 years, development practices need to be questioned.
Just as intensive farming in flood plains reduces the amount of land to buffer the runoff from heavy rains, more highways, parking lots and subdivisions increase the runoff. And that same development in flood plans means more homes and businesses at risk.
The fear of crimping economic growth often means we have communities with slight flood plain management. And, with little coordination between communities, planners too often fail to take into account future growth and development upstream that might worsen flood conditions.
Riverfront communities put too much faith in levees to keep the water back. But levees tend to make the problem worse by confining rivers and increasing flooding further downstream.
That is, if the levees hold. The failures of more than 20 levees along the Mississippi River in the past couple of weeks shows the futility of trying to build higher and higher walls to keep back flood waters that seem to get higher with each new flood season.
The standards for building levees is not particularly high. If a levee is built to a 100-year standard -- meaning there is only a 1 percent chance in any given year that water will breech it -- that's sufficient enough protection for a property owner to qualify for the National Food Insurance Program.
By comparison, in the Netherlands -- a low-lying country under constant siege from rising ocean waters -- ocean levees are built to a 10,000-year standard and inland levees are usually built to meet a 1,250-year standard.
Apparently, none of the lessons learned from Hurricane Katrina in 2005 and the catastrophic failure of New Orleans' levee system have been learned. There is no federal inventory or inspection system in place and the Army Corps of Engineers is lacking the resources to repair, maintain and upgrade levees around the country.
And the wild card in all this is climate change. Many scientists agree that climate change will increase the occurrence and severity of storms as well as droughts, increasing the chances of more floods in Iowa like 1993 and this year's disaster.
We can't be smug here. The network of flood control dams built in New England after the catastrophic floods of 1927, 1936 and 1938 have kept the Connecticut River in check in the spring, but in recent years, flash flooding seems to happen with more regularity in Vermont. Again, climate change and development decisions play in role in this.
For too long, we have tried to get the upper hand on nature. But nature always seems to have a way to up the ante. Until we learn to live in harmony with nature, instead of trying to bend it to our will, we will see more "natural" disasters with man's fingerprints all over them.
© 2008 Reformer