Description

Geodynamics was contracted to perform a comprehensive topo-bathy survey of the Masonboro Inlet south jetty in New Hanover County, NC.  This work included mapping both the sub-aqueous and sub-aerial portions of the rock jetty, as well as the inlet complex adjacent to the hard structure.  This work was performed using a high-resolution multibeam sonar (Kongsberg EM3002-D), a mobile laser scanner (Dynascan M250 LiDAR) mounted on both topographic and marine platforms, and singlebeam sonar (Odom CV100) soundings.  All geographic data was corrected with RTK-GPS corrections provided by the NC Geodetic Survey’s CORS network.

The multibeam bathymetry data was collected in accordance with IHO Special Order and USACE standards for navigation and dredging requirements to provide accurate depths and detailed information on morphology.  All laser scanning practices were performed following a complete calibration of antenna separation, sensor alignment, and ambiguities on a single mounting platform that was exchanged between marine and topographic platforms.  All equipment preparations and survey operations were performed with rigorous QA/QC practices to provide reliable data.

XYZ point files from all three data sources were then merged into a single file and viewed in a point cloud viewer to analyze overlap, data coverage, and elevation consistency.  Overlapping portions of data were cleaned to enhance the quality of the final data.  The dataset was then modeled in various ways so that the end user would have flexibility when analyzing the data and using various software, including final deliverables in inRoads (DTM and DGN) and a Digital Elevation Model (DEM).