A natural sponge
Wetlands help reduce flooding by storing water and releasing it slowly,
like a sponge. This seeping action also filters out pollutants.
Over the past two centuries, Missouri and Illinois have lost more than 80 percent
of their wetlands, as they have been drained and filled to make room for farmland
and other development.
Nowhere to go
Replacing wetlands by levees forces the water into a narrower channel. Deprived of
its natural drainage system, the river gets higher and faster, increasing the chance