Coastal wetlands are particularly valuable in reducing storm damage. Coastal wetlands, including salt marshes and mangrove swamps, are the first line of defense to reduce the impacts of hurricanes and other ocean storms on coastal areas. Although coastal marshes can sustain some storm damage, they generally rebound quickly and prevent millions of dollars in damage to coastal cities. However, as wetlands are fragmented and destroyed due to development and other activities, their effectiveness decreases.

It is estimated that storm surges are reduced by 1 foot for every 2.7 miles of coastal wetlands that are in place. Hurricane Katrina in 2005 resulted in over 1,500 deaths and caused 40 to 50 billion dollars in losses in Louisiana, most of which occurred in New Orleans. Various estimates indicate that this damage and loss of lives could have been drastically reduced if many of the historical wetland were still in place. Nonetheless, loss of lives and damage to buildings would still likely have occurred even if all wetlands were still in place based on the location of New Orleans. However, the importance of keeping coastal wetlands intact is evident in reducing the impacts of storms.