Center for Coastal Resources Management

7c. CONSTRUCT A BREAKWATER AND ADD BEACH NOURISHMENT

It is sometimes difficult to observe the shoreline to determine whether the intertidal zone is sandy or muddy. Even if no beach is obvious, high energy shorelines are likely to be sandy systems. The presence of sandy banks, nearshore sand bars, and nearby beaches suggests a sandy intertidal zone and thus the presence of a beach. An off-shore breakwater system with beach nourishment is the preferable approach. A breakwater system reduces the height and angle of oncoming waves, thereby reducing associated erosion of the beach and shoreline. Beach nourishment enhances the natural capacity of the beach to provide erosion protection by providing distance between the bank and tidal action and allowing for wave run-up. The wider the created beach, the greater the upland protection provided by the nourishment. In areas with active erosion, a sill or breakwater may be used to prevent erosion of the nourishment material.
Allowing the breakwaters to accrete sand naturally steals sand from the existing sand supply and may create or worsen erosion on nearby properties. Beach nourishment allows for the creation of a beach without removal of sand from the system. The material used for artificial nourishment should be clean sand of a grain size composition similar to that currently existing on the beach. Placement of offshore structures should take into consideration the existence of other resources such as submerged aquatic vegetation (SAV) and oyster reefs, and avoid impacting them where possible. Where there’s a conflict, constructing an onshore revetment may be more appropriate.

Return to the Decision Tree Homepage

In an area with minimal or eroded beach, no marsh, high fetch and deepwater, a breakwater with beach nourishment would provide the shoreline with a protective beach.