Species that live near rivers and floodplains have specially adapted to floods and even need them to survive. Floods help flush water systems and carry nutrients to nearby areas like floodplains. However, floods can be very destructive to human property. Wetlands help control floods by absorbing large volumes of water, protecting cities and towns. Studies have found that when wetlands are destroyed, flooding increases significantly.
Wetlands help scientists predict floods because they can be observed over time.
Scientists know how water will behave in a wetland. However, when wetlands are destroyed, scientists lose an important prediction tool. Sometimes flood-control structures help. However, if people build a dam, and then build their town right behind the dam, they are putting themselves at risk. A dam does not replace a wetland because it only holds back the water rather than dissipating the water underground.