Battling Rivers Slide Show

Civilization's Love-Hate Relationship with Rivers

A lot of history books say that civilization started with agriculture. But without rivers to float goods to market, agriculture couldn't have gotten very far. So perhaps civilization really kicked into high gear with the invention of the raft. The result is that many of the world's major cities grew up on the banks of rivers. We all know the downside to this arrangement: All rivers can flood and so cities on rivers face the possibility of periodic devastation. In the United States alone about 3,800 towns and cities with populations of more than 2,500 are threatened by river flooding. Here is a selection of some of civilization's ongoing river battles, along with some of the surprising ways humans can make flooding worse.

English Flash Floods

When we hear the words "flash flood," we generally think of the quick floods caused by desert thunderstorms in Arizona or another cactus-studded desert land. In 2007, however, it was verdant England that became flash flood central. In this September 7, 2007 image from Upton-Upon-Severn, flood barriers protect the Plough Inn. Because of a highly unusual storm dumping as much as a month's worth of rain in a single day, there were floods all over England. Why did it happen? Is it an effect of global warming? Most Brits no longer require an expert opinion to answer that question.

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