ASCE Policy Statement 498
Approved by the Energy, Environment, and Water Policy Committee on January 24, 2012
Approved by the Public Policy Committee on May 4, 2012
Adopted by the Board of Direction on July 20, 2012
The American Society of Civil Engineers (ASCE) supports:
- Efforts to reduce land loss along America’s coastal wetlands through protection and restoration of the physical processes necessary to sustain these unique ecosystems. ASCE supports the ongoing effort to fund and implement the beneficial use of dredged material, regional sediment management, and a programmatic authorization of federal civil works projects that allow restoration and preservation work to continue on a long-term basis.
- The principle that coastal and wetland restoration and hurricane protection must be part of an integrated regional watershed and coastal zone management effort, which considers the interrelationships of natural, social and economic systems and includes federal, state, local and private initiatives in a collaborative way.
- Continued funding for wetland preservation and restoration projects under the Coastal Wetlands, Planning, Protection and Restoration Act of 1990 (CWPPRA).
America’s coastal states—those states bordering on the Atlantic, Pacific, or Arctic Ocean, the Gulf of Mexico, Long Island Sound, and one or more of the Great Lakes—contain vital ecological and economic resources. These resources are threatened. For example, the Louisiana coastal wetlands have been disappearing through land subsidence and erosion at an alarming rate of 25 to 35 square miles annually. Since 1930, over 1,800 square miles have been lost. It is estimated that an additional net loss of more than 500 square miles may occur by the year 2050. The rate of this land loss is some of the highest in the world and exposes communities and critical infrastructure to damage from storm surge as Hurricanes Katrina and Rita vividly demonstrated. The levee system that was constructed for flood control on the Mississippi River, while acknowledged for its beneficial aspects, is one of several reasons for the coastal land loss. Other reasons include land subsidence from oil and gas extraction activity in the coastal area, naturally occurring land subsidence, erosion, and the rise in sea level. Regional sediment management offers a strategy that may be able to balance the different causes of land loss and their potential remedies.
One of the largest deltaic systems in the world, Louisiana’s coastal wetlands are a highly productive area and an important base of the United States' economy and energy security. It is the home of the critical U.S. Strategic Petroleum Reserve. The loss of coastal area means that this population, which includes the City of New Orleans, will experience increasing vulnerability to hurricanes, including storm surges that top levees and cause severe flooding. Hurricanes Katrina and Rita highlighted this increased vulnerability.
Since the CWPPRA was enacted in 1990 it has authorized 151 restoration or protection projects, benefiting more than 110,000 acres in Louisiana.
The economic investments described above indicate there is a significant cost savings in acting now to protect and restore America’s coastal wetlands. Restoring wetlands can provide a level of flood attenuation to storm surge and protection from erosive forces, as well as valuable ecological benefits.
Project managers, scientists, and engineers use a variety of techniques to protect, enhance, or restore wetlands. Each restoration project may use one or more techniques to repair delicate wetlands. These techniques include marsh creation and restoration; shoreline protection; hydrologic restoration; beneficial use of dredged material; terracing; sediment trapping; vegetative planting; barrier island restoration; and bank stabilization
ASCE Policy Statement 498
First Approved in 2003