The Washington Post said Tuesday as the river recedes, there are some 13 million sandbags containing tons of wet, smelly sand that will have to be disposed of.

"If sandbags are doing their jobs, then they're absorbing floodwater," said Kevin Baskins, spokesman for the Iowa Department of Natural Resources, "which includes fuels, chemicals and other bacteria."

While volunteers poured in to help build up the levees around threatened communities, the sandbags will be largely left to the weary residents to take down while also trying to clean up flooded homes and businesses.

"Nobody wants to come help move them," Steven Watson told the Post. He said he had 2,000 sandbags around his Buffalo, Iowa home and that he and his wife had only managed to remove about a quarter of them in one eight-hour day.