A design has been selected using Reef Ball™
units as an offshore reef breakwater. Reef Balls are hollow
concrete hemispheres designed for marine habitat enhancement.
Placed in parallel rows as an offshore breakwater, Reef Balls
will reduce the wave energy reaching the beach both by
physically blocking the incident waves and by generating
turbulence through the interstices in and around the concrete
units.
Reef Balls are usually fastened to a hard substrate with
fiberglass reinforcing bars. However, the Miami site has a
sandy substrate. To provide stability and prevent the units
from sinking into the sand, the Reef Balls will be mounted on
concrete articulated mattresses placed on a bedding layer.
The purpose of the breakwater is to reduce wave energy
reaching the beach, thereby reducing the movement of the sand,
extending the time between renourishments, and increasing the
storm protection to adjacent buildings. Additional benefits of
the Reef Ball design include improved habitat for marine life,
and as the Reef Balls become covered with marine growth, the
design will provide recreational benefits as a snorkeling
trail.
The primary objective of the demonstration project is to
hold the maintain template dimensions between renourishment in
an innovative or nontraditional manner. This demonstration
project will also document the performance other
nontraditional methods implemented maintain the beach
nourishment design template at other erosional hot spots in
the BEC&HP (e.g., use submerged rubble-mound reef for wave
attenuation, and use of T-head groins or headland structures
for sediment retention).
