Pitfalls of Ebb-Shoal Mining

Abstract

AbstractEbb-tidal deltas or ebb shoals in moderate to high-energy environments often contain well-washed sandy sediments. These clean sands attract the attention of coastal engineers because they are commonly suitable for shore protection efforts such as beach renourishment (replenishment), dune restoration, and marsh remediation. Ebb-tidal deltas are sediment sinks where sandy materials are sequestered in deposits that can build up to such significant proportions that they form large coastal salients. In addition to sediments debouching from the inlet, longshore sediments are either trapped in the shoal or are bypassed in swash bars. Accumulation of sediments in these depocenters at the mouths of inlets often appear as a ready-made point borrow source that can be accessed for shore protection by dredging and placement on adjacent eroded shores. Ebb-tidal deltas are, however, in delicate balance with inlets, longshore drift, beach-dune systems and overall coastal stability. Removal of sediment volume by dredging from deltas interrupts the sand-sharing balance between inlets, ebb-tidal shoals, coupled beach-dune systems, wetlands, and shoreline stability.KeywordsTidal PrismBeach ErosionLittoral DriftErosion FrontLongshore DriftThese keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.