DATE: June 1972 LOCATION: South Dakota DEATHS: 238, with more than 3,000 injured ESTIMATED COST: $826 million * WHAT HAPPENED: Rains over the Black Hills produced record floods on Rapid Creek and other area streams. Heavy debris in the floodwaters clogged the spillway of the Canyon Lake Dam, which failed, sending a flood wave into Rapid City. Much of the damage occurred because people were living in the floodway. After the event, housing was relocated, but many businesses were allowed to remain. *All costs estimated in 2009 dollars. ... Read More

DATE: May through September 1993 LOCATION: Illinois, Iowa, Kansas, Minnesota, Missouri, Nebraska, North Dakota, South Dakota, Wisconsin DEATHS: 47 Estimated COST: nearly $30 billion* WHAT HAPPENED: Sustained rainfall generated exceptional flood levels throughout the region. Hundreds of levees were breached along the Mississippi and Missouri rivers, and 70,000 homes were damaged, many in areas that people assumed to be safe. *All costs estimated in 2009 dollars. ... Read More

DATE: January and March 1995 LOCATION: California DEATHS: 27 ESTIMATED COST: $4 billion* WHAT HAPPENED: "El Niño" conditions brought strong storms, producing floods that led to federal disaster declarations in 57 of the state's 58 counties. Along the Russian River, the accumulation of vegetation and debris reduced the stream's capacity, raising water levels to record highs. Heavy development in floodplains elsewhere led to bridge collapses and flooded downtowns, including San Jose's. In the Sacramento River Valley, a particularly hard-hit area, storm drainage system failures were ... Read More

DATE: June 2008 LOCATION: Illinois, Iowa, Minnesota, Missouri, Wisconsin DEATHS: 24 ESTIMATED COST: $15 billion* WHAT HAPPENED: Despite lasting just weeks and breaching only a few dozen levees, these Midwestern floods still caused serious damage, partly because more people and property were at risk than in the 1993 floods that affected many of the same areas. In the 15 years between the two storms, the population in the areas' 500-year floodplain increased by 17 percent, with the number of the people living in the area flooded in 1993 rising by 18 percent. *All costs estimated ... Read More