Dam Catastrophes Can Be Prevented

Last week, more than 10,000 people in central Michigan were evacuated when a rain-swollen artificial lake breached two dams in a row. Nobody died in the resulting “500-year flood,” but countless homes and businesses, including a chemical plant, were inundated. Damage could reach nearly $900 million.

Dam failures aren’t as rare as you might think: In the U.S., they happen roughly two dozen times a year. Most are minor, but some cause catastrophic flooding, billions of dollars of damage, and even deaths. Last year, a breach in Nebraska unleashed an 11-foot wave, killing one person before flooding three counties. In 2006, a dam breach in Hawaii dumped 400,000 gallons of water downstream, leaving seven dead. All told, some 1,700 dams across the U.S. pose a risk to human life, according to one recent analysis.