By James D. Fraser, Sarah M. Karpanty and Daniel H. Catlin
HURRICANE Sandy confirmed what Irene and Katrina had suggested: We will retreat from the edge of the sea.
We should do so in a planned, organized manner that protects citizens' interests and the ecological, economic, recreational and aesthetic values of our coasts. This endeavor will require major changes in the way we manage coastal lands.
Coastal storms have killed thousands of people and have caused more than $250 billion in damages in the past 12 years. Costs are increasing with each storm because more and more people live, and build infrastructure, in risky places.
Hundreds of thousands of people live on barrier islands along the East and Gulf Coasts. The nature of these low-lying sand islands is to move. Winds, waves and currents, independent of hurricanes, cause barrier islands to roll toward the shore and migrate along the coast.
Put another way, they naturally migrate from under buildings placed on them. The population density of U.S. coastal counties increased 28 percent from 1980 to 2003, to about 153 million.
Clearly, coastal development must be rethought.
Billions of dollars have been spent building seawalls, jetties, beaches and dunes in efforts to control water flow and sediment movement and, ultimately, to stabilize dynamic shorelines to protect people and property.
Since 1922, "renourishment" sand has been pumped on more than 3,700 miles of beach in the United States. That's equivalent to the distance from Bangor, Maine, to Miami and back.
Unfortunately, these efforts have often failed. All engineered solutions, whether "hard construction" such as seawalls or "soft construction" like dunes and beaches, have a limited life and have to be rebuilt repeatedly.
In addition to human and monetary costs, attempts to stabilize naturally dynamic shorelines have ecological costs.
Many coastal plants and animals have adapted to eroding, shifting shorelines. They are integral parts of the food webs that support fish and wildlife species important to commerce, recreation and aesthetics.
If humans succeeded in stabilizing the shoreline, many species, and the ecological, recreational and economic benefits they produce, would be at risk of extinction.
For decades, federal, state and local agencies have made legislative and regulatory efforts - including the National Flood Insurance Act of 1968, the Coastal Zone Management Act of 1973, the National Flood Insurance Reform Act of 1994 and the Flood Insurance Reform Act of 2004 - to address these concerns.