The U.S. Army Corps of Engineers, Jacksonville District (USACE) is tasked with maintenance dredging the Federal Navigation Channel, interior flood shoal, and sedimentation basin in the vicinity of St. Lucie Inlet. Depths in the survey area ranged from 3 to 12 feet, which extended from the approximate equilibrium toe-of-fill line seaward 500 feet along 11 nautical miles of the beach.
Dredge material of appropriate quality (sand) is bypassed from these areas to the beaches of Jupiter Island, Martin County, Florida. The sand transfer activity is located within the waters of St. Lucie Inlet and along the beaches of Jupiter Island (between the inlet’s south jetty at Florida Department of Environmental Protection (FDEP) reference monuments R-45 and R 117).
FDEP has determined that an extensive nearshore hardbottom community exists immediately south of St. Lucie Inlet and north of R-87. In order to assess potential impacts to these communities by proposed sand transfer activity, USACE required charac¬terization and analysis of potential hardbottom resources identified within the vicinity of the project.
ANAMAR conducted a nearshore sidescan survey in February 2010 to collect high-frequency sidescan sonar data to determine the presence and extent of nearshore hardbottom communities for this purpose. ANAMAR was responsible for collecting, processing, and analyzing sidescan data to identify benthic communities that could be impacted by dredge material placement.