Shoreline armoring is the construction of barriers or structures for the purpose of preventing coastal erosion and/or manipulating ocean currents. Although they may prevent the deterioration of the immediate shoreline, these man-made structures almost always exacerbate erosion problems at nearby, downstream beaches by changing wave patterns and water flow.

Armoring may also promote the loss of shoreline vegetation, which in turn can degrade the ecosystem that seabirds and other beach and sea-dwelling life depend upon. By altering water flow and erosion and deposition and creating physical barriers, some types of shoreline armoring prevent sea turtles from reaching their nesting sites on shore. Finally, shoreline structures can block sunlight imperative to aquatic plants such as eelgrass, a prime habitat for herring and other marine life.

Shoreline erosion is a natural process determined by a complex array of environmental causes. Weather changes, tidal currents, and sea level...