3 - Dune Building Practices and Impacts

Summary

Chapter 3 discusses the ways foredunes can be built by human actions in locations where they have been eliminated. Alternative strategies for foredune development are reviewed including (1) using beach nourishment to provide a beach with sediment sizes that can be reworked by waves and winds; (2) constructing dunes by using earth-moving equipment to place fill sediment derived from external source areas, such as offshore borrow areas, navigation channels, or inland deposits; (3) using in-situ beach sand using earth-moving equipment (termed grading or scraping); (4) deploying sand-trapping fences; (5) planting vegetation; and (6) using a combination or multiple of these strategies. Time and space are critical to the evolution of landforms and vegetation gradients on developed coasts, and choice of techniques for dune building are evaluated under these constraints. The case is made that once newly built foredunes achieve their protective function, they should be allowed to evolve as naturally functioning environments to the extent allowable.