Water is one of the most useful things on Earth.
We drink it, bathe in it, clean with it and use it to cook food. Most of the time, it is completely benign. But in large enough quantities, the very same stuff we use to rinse a toothbrush can overturn cars, demolish houses and even kill. Flooding has claimed millions of lives in the last hundred years alone, more than any other weather phenomenon. FEMA News Photo Heavy rains in the spring of 2001 flooded Davenport, Iowa.