they have an adverse aesthetic effect on the beach and can limit use or access to the shore. Their use by a
single landowner is generally a problem because they are subject to flanking. Breakwaters are also well
suited because they trap and hold sand moving both alongshore and on or offshore. However, they can
cause extensive downdrift erosion damages and they are expensive to build. Groins can effectively build
beaches on their updrift sides but can also cause accelerated downdrift erosion. Their functional behavior
is complex and difficult to predict. Beach fills retain the natural form and character of the beach and
enhance its recreational potential. Local sources of suitable sand are not always available, however, and
fills require periodic renourishment. Vegetation, effective in low wave energy situations, has low initial
costs and enhances natural appearance. Unfortunately, foot and vehicular traffic damage plantings.
Drainage controls and slope flattening are not applicable to beach shorelines. Perched breaches are
ideally suited as they increase the available beach area. Combination methods are often excellent, such
as a perched beach that is further stabilized with vegetation.
Wetlands
Erosion control structures built near wetlands should be placed at a low bluff or beach behind the
marsh. For protection of the marsh itself, vegetation is the only appropriate alternative. To assist
establishment of plantings, however, small temporary breakwaters may be required. Beach fills or
perched beaches may also be used to provide a suitable substrate for planting in some areas.
EFFECTS ON COASTAL PROCESSES AND ADJACENT PROPERTIES
Table 2 lists the effects of various options on shoreline processes.
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