Clean Water Act Section 404 and Coastal Marsh Sustainability

摘要

The "no net wetland loss" goal has not been met in urban coastal regions where conditions continue to exacerbate wetland losses. Under the Clean Water Act (Section 404) the U. S. Army Corps of Engineers and U.S. Environmental Protection Agency share responsibility for regulating placement of fill material in wetlands. The 'no discharge of fill' rules threaten coastal wetlands with continuing losses due to effects of changing climate, including rising sea levels, higher storm surges, and flooding. Where inland migration is limited by development, or where sediment accretion rates are lower than the rate of sea level rise, urban wetlands will be lost unless marsh topography is elevated. We explored regulatory and design approaches in recent Hudson-Raritan Estuary (HRE), San Francisco Bay Estuary and coastal Louisiana restorations, including creation of new marshland using dredge material. Questions related to sea level rise, ecological position within the landscape, or potential effects of extreme storm events were not addressed in the HRE restoration designs; these concerns were taken into account in other regions. We suggest benefits of marsh 'replenishment' should be acknowledged in Federal regulatory policy and that consistent policies supportive of low-lying coastal marsh preservation in all regions should be enacted.