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10 st / September 2015 www.sea-technology.com water features to rejected sound- ing status. Altogether these tech- niques provided an exceptional opportunity for directed editing and classifcation of the numer- ous complex shallow-water and shoreline features encountered in the survey area. Survey Area Description OSI was tasked by NOAA's Offce of Coast Survey with completing a "Navigable Area" hydrographic survey to meet "Object Detection" coverage standards within the survey area, which included Jamaica Bay, a water body bounded by the New York City boroughs of Brooklyn and Queens. Much of the Jamaica Bay survey area fell within a high-traffc water- way surrounded by a complex, multifaceted coastline last surveyed more than 40 years ago. Prior to Hurricane Sandy, there was a documented prob- lem with abandoned derelict vessels and marine debris within Jamaica Bay. According to NOAA's Marine Debris Program, the Hurricane Sandy storm surge deposited an overwhelming amount of large marine debris (i.e., boats, docks, pilings, construction debris) within the surrounding communities of Jamaica Bay. Given the pre-existing marine debris problem compounded by the Hurricane Sandy de- struction, Jamaica Bay proved to be a formidable site for hydrographic surveying and debris mapping. Data Acquisition Methods During the course of the survey, more than 1,500 naut. trackline mi. of mainscheme and feature development MBES and side scan sonar (SSS) data were acquired. The MBES transducer was deployed in both down-looking and side- looking orientations. The side-looking approach involved rotating the MBES transducer nominally 45° to starboard, thereby focusing soundings away from the survey vessel, in- creasing coverage in shallow water. This approach allowed S horeline feature and debris mapping within a dense ur- ban environment introduces a heightened level of complexity not often encountered in hy- drographic surveying, particu- larly when the survey follows an unprecedented storm event such as Hurricane Sandy. In the fall-winter of 2013, Ocean Surveys, Inc. (OSI) completed such a survey within Lower Bay, Rockaway Inlet and Jamai- ca Bay, New York. More than 1,400 wrecks and obstructions, in various states of disrepair and exposure, were identifed within the survey area. OSI developed data acquisition and processing methods to as- sist with the accurate classifcation and attribution of the relatively massive volume of debris and shoreline features that were found. While survey methods combining multibeam echo- sounder (MBES) acquisition with vessel-mounted topo- graphic laser scanners have proven successful for shoreline mapping, employing such an approach was beyond the project scope of work and budget due to the added expense of the hardware and additional data processing required. In- stead, OSI employed a low-cost method of acquisition and subsequent utilization of video and photo documentation of the debris-strewn shoreline in conjunction with side-look- ing MBES soundings at various stages of tide. The products were rendered from acquisition of shoreline video and still photography and time-synced with the sur- vey vessel's GPS positioning. They proved to be a valuable tool for shoreline feature correlation and classifcation. In addition to the photo documentation of above-water shore- line features, "high-water" objects such as piers, pilings, bridges, and foating docks visible below the water's surface in the MBES data were classifed during data processing with a distinct sounding fag to separate the surface features from submerged features, rather than relegating the high- Survey, Data Processing Methods For Post-Hurricane Sandy Survey Methods Aid in Object Detection, Complex Feature Management By Bonnie L. Johnston • Robert M. Wallace • David T. Somers Marine debris in the intertidal zone, Jamaica Bay, New York.