An engineered beach and dune system provides coastal protection based on engineering calculations following extensive study by USACE. These calculations establish the appropriate width and slope of beaches and the size and location of dunes (where necessary) to protect New York’s shoreline. Engineered beach and dune systems are designed to provide protection from flood and wave damage caused by storms.
The FIMP dune line was determined by USACE taking into effect various factors including the costs and benefits of placing the dune line further south or north and determined the line that provided the best benefit for the cost. The alignment is not straight as it follows the natural contour of the land to match the existing topography.