The ability of wetlands to control erosion, is so valuable that some states are restoring wetlands in coastal areas to buffer the storm surges from hurricanes and tropical storms. Wetlands located at the margins of lakes, rivers, bays, and the oceans, are protecting shorelines and stream banks against erosion. Wetland plants, are holding the soil in place with their roots, absorbing the energy of waves, and breaking up the flow of stream or river currents.