<http://schema.org/description>
"The Hoover Dam holds back 10 trillion gallons of water. That&amp;#039;s enough to cover the state of Connecticut 10 feet deep. How much damage would be done if the dam broke?"^^<http://www.w3.org/2001/XMLSchema#string>
<http://science.howstuffworks.com/engineering/structural/hoover-dam-broke1.htm>