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 many
sheltered areas, has low initial costs and enhances the natural appearance and beauty of the shoreline.
Unfortunately, foot and vehicular traffic damage plantings. Drainage controls and slope flattening are
not applicable. Perched beaches can be used in some areas where fills alone would be too large to be
economical, or where larger wave action is a problem. Combination approaches are often excellent, such
as a perched beach that is further stabilized by vegetation.
Wetlands. Structures built near wetlands are usually placed at a low bluff or beach behind the
marsh. For protection of the marsh itself, vegetation is the only appropriate alternative. To assist in
establishing 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.
Applicability to Shoreline Uses
Some methods lend themselves more readily than others to particular shoreline uses. It is
important to choose a method that performs its function and does not interfere with the planned use of the
shoreline. No action obviously does not enhance shoreline uses, although continued erosion may have an
adverse impact. Relocation involves similar considerations. Bulkheads create an access problem unless
stairs are provided. Vertical structures may also cause wave reflections that can erode the remaining
beach material. Bulkheads are necessary when some water depth for boating activities is needed at the
shore. Revetments of randomly placed rough stone may hinder access to the beach. Smooth structures,
such as concrete blocks, cause less difficulty for walkers. Breakwaters provide an area sheltered from
waves, but they can hinder circulation and cause water quality problems. Beaches built behind
breakwaters have enhanced recreational potential. Rough stone structures may provide an improved
habitat for certain fish species but may be hazardous to climbers. High structures may also intrude on the
view of the water and be aesthetically undesirable. Groins may hinder travel along the beach, but any
sand they trap improves the beach conditions. Beach fills enhance recreational uses of 'the shore, but
increased turbidity during construction can temporarily harm certain fin and shellfish species.
Vegetation greatly improves the natural habitat but hinders other uses of the beach because traffic
through the plantings must be restricted. Drainage controls have little impact on shoreline uses and slope
flattening reduces the available land at the shore. Perched beaches provide a recreational beach. A
vertical sill may pose a hazard to bathers because of the sudden step to deeper water, but it may provide
improved access for fishing. A rock sill may provide a natural habitat for fin and shellfish and may not
be as hazardous to bathers.
Conditions in the General Area
Conditions in the local area can strongly influence the selection of an alternative. One of the most
important considerations is the possible effects on downdrift properties. Accretion devices (breakwaters
and groins) trap sand moving along the beach and tend to starve the downdrift shoreline. If this would
cause damages to neighboring properties, the area behind the breakwater or updrift from the groin must
be partially filled so that littoral material bypasses the structure, and downdrift damages are avoided.
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