Ecological engineering, design, and construction considerations for marsh restorations in Delaware Bay, USA

Public Service Electric & Gas of New Jersey is restoring approximately 4050 ha of salt marsh along Delaware Bay, USA, to offset possible effects on fish populations in the Bay from their existing once-through cooling system. Planning for this effort started with addressing three questions: Do marshes contribute significantly to fish production? How much marsh produces how much fish? Which marshes should be restored? There is ample evidence that salt marshes produce fish. The area of marsh necessary to offset potential losses was calculated from a simple aggregated food chain model and multiplied by four to provide a comfort level to the regulatory agencies. Marshes chosen for restoration were former salt marshes at appropriate tidal elevations. Planning involved experts in marsh ecology, hydrology, and engineering working with the company and regulatory agencies to establish clearly defined goals for the project. Design followed the advice of the experts and construction was overseen to follow the design. Long-term follow up is through adaptive management that is scheduled to continue for about a decade, depending upon progress of the restoration toward its goals.