Without wetlands, it's impossible for harmful compounds like chemical fertilizers to be filtered out of the environment. Wetlands are also critical for controlling floods. Like sponges, wetlands absorb heavy rain or snowmelt and slowly release manageable amounts of water back into the surrounding area. This sponge-like ability allows even a small wetland to absorb and hold a surprising amount of water. For example, a prairie pothole just one acre in size can store up to 1.5 million gallons of water.
Some wetlands also serve as key seasonal water storage areas.
The remarkable sponge-like quality of wetlands means they also prevent devastating flood damage, saving human lives and property. Scientists believe severe U.S. flood damage in recent years is in part due to large-scale wetlands destruction along rivers and in coastal areas. In destroying wetlands, we've eliminated nature's ability to effectively deal with a sudden influx of water. Without wetlands, flood water has no place to go-except people's homes, farms, and businesses. Many developed cultures historically have had an uneasy relationship with wetlands.