|Placement nears completion on one of the
limerock reef installaions.
Broward County Mitigation Completed
Where can you find 8,000 limerock boulders within snorkeling
distance from shore? Offshore from Dania Beach, Hollywood
Beach, and Hallandale Beach in Broward County. Construction
is complete for the county’s mitigation for the Segment
III (Port Everglades to the south County line) Shore Protection
Project. At a cost of $6 million, the boulders were placed
at threenearshore sites to create 10.1 acres of artificial
reef, compensating for 7.6 acres of future impacts by the
beach project to nearshore hardbottoms. Placement was completed
by Coastal Systems Development, Inc. (CSD) between June 2003
and September 2003.
Just prior to placement, CSD updated nearshore hard bottom
locations, enabling the County to consolidate several sites
into two large and one small mitigation areas. The close proximity
of sensitive hard bottom substrate and shallow water depths
of 15 feet (only 300 feet offshore) required that specialized
moorings be designed for the crane barge.
Oceangoing tugs towed barges to transport 66,000 tons of boulders
from quarries in Freeport, Grand Bahamas, to the project sites.
The placement of the boulders was precisely controlled using
a crane equipped with a DGPS positioning system, allowing
a position to be obtained for each boulder. Crews worked around
the clock during favorable weather conditions to complete
the massive project in less than four months.
The county met their goal of having the mitigation constructed
prior to beach construction (currently scheduled for June
2004), as preferred by regulatory and resource agencies as
a way to maximize the value of the new habitat. The limerock
resembles natural reef substrate and is already providing
habitat for encrusting and boring organisms as well as fish
As an added benefit, stony corals over 15 cm in diameter will
be relocated from the impact areas to the mitigation site
to protect the organisms and to accelerate the productivity
of the mitigation.
R. Harvey Sasso, P.E.-Principal, CSI
Stephen Higgins-Broward County, D.P.E.P