Albemarle Sound Hydrographic Survey
The Albemarle Sound, one of the longest estuaries in North Carolina, spans from the Outer Banks to expansive wetlands, rivers, and marshes. NOAA’s Office of Coast Survey (OCS) contracted NV5 to survey the bathymetry of the Sound, a region that hadn’t been surveyed for navigation or marine hazards since the 1920s.
NV5’s survey covered 475 square nautical miles, using a pioneering Coastal Resilience Charting approach. The resulting high-resolution bathymetric products will update NOAA’s nautical charts and support coastal resilience modeling, including inundation mapping, salinity gradient mapping, and habitat mapping.
Innovative Survey Approach: The survey area posed unique challenges due to its shallow nature and lack of modern bathymetric data. NV5 deployed a fleet of six survey platforms, including two Uncrewed Surface Vessels (USVs), to capture data across varying depths and conditions. Multibeam echosounders (MBES), singlebeam echosounders (SBES), and sidescan sonar (SSS) sensors were used to map the bathymetry, capture seabed sediment characteristics, and identify potential hazards.
Data Management and Quality Control: To manage the large volume of data, NV5 developed a customized GIS solution, the Survey Information Management System (SIMS), for real-time data validation and project management. SIMS enabled NV5 to perform quality control on mosaics and assess data line-by-line. This approach also uncovered over 100 previously uncharted dangers to navigation (DToNs).
Meeting Dual Objectives: NV5 adapted its data processing workflow to meet both nautical charting and coastal resilience objectives. By blending different mapping and processing software, NV5 ensured the data complied with NOAA’s nautical charting standards while also supporting coastal resilience efforts.
