Chapter 5 



ALTERNATIVES FOR PROTECTING COASTAL WETLANDS 



FROM THE RISING SEA 



by 



Office of Wetland Protection 



U.S. Environmental Protection Agency 



Editor's Note: After reviewing the preceding chapters, EPA's Office of Wetland Protection 

 prepared this concluding chapter, which presents their recommendations for protecting coastal 

 wetlands. 



Recognizing the numerous benefits and values accrued to society from wetlands, there are 

 several options available for minimizing potential future losses of wetlands from predicted sea 

 level rise. These protection alternatives focus on methods available to local planners and 

 decisionmakers who can influence regional efforts to ameliorate the impacts on coastal resources 

 associated with sea level rise. 



1. Increase wetlands' ability to keep pace with sea level rise. 



The ability of wetlands to keep pace with the rising sea will depend in large part on the 

 availability of a reliable sediment source. Both natural and artificial methods for ensuring 

 adequate sedimentation rates would contribute to marsh accretion and development, thereby 

 maintaining the marsh surface level above mean low water. Diversion projects, levee 

 construction, and channelization efforts should each be evaluated in terms of their impacts on 

 supplying necessary sediment. In instances where wetlands are currently subsiding, planners 

 should consider means to increase sediment supply, including river rediversion, levee lowering, 

 jetty construction, or artificial sedimentation practices (e.g., spreading clean dredged material 

 over a wetland; of course, this practice is not necessary for healthy wetlands, only for those in 

 danger of converting to open water due to inadequate sediment nourishment). 



2. Protect coastal barriers. 



Coastal barrier islands play a critical role in ameliorating the destructive force of wave action 

 on wetlands located landward of the island. The erosive force of the sea will increase as sea level 

 rises and will subsequently play a greater role in destroying wetlands, particularly during storm 

 events. Local efforts to ensure the protection of barrier islands will in turn have a positive impact 

 on preserving the wetlands that lie behind them. 



3. Create no-development buffers along the landward edge of wetlands. 



As sea level rises, a natural adaptation would permit the existing wetlands to migrate 

 landward to reestablish in inundated areas that currently are uplands. This migration is limited 

 to upland areas that are not developed or bulkheaded. Preventing the development of upland 

 areas adjacent to wetlands could be accomplished through acquisition or regulation (e.g., zoning 

 restrictions). These buffers would also serve to reduce the impacts of nonpoint source pollution 

 of the estuary, and the combination of these benefits should contribute to making this option 

 cost-effective. 



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