The Mississippi and its tributaries, like the Des Moines and Iowa Rivers, are just starting to recover from high water. During flooding events, large amounts of debris will be fl ushed out of the river system and can be seen floating downstream from almost anywhere along the banks. When people talk about cleaning up after a Mississippi River flood, they usually talk of lots of mud, some piles of sand and a few stray logs here and there but employees from locks on the lower half of the District have a different idea of river clean up after a flood.