UNH Ocean Seminar

Further Analysis of EdgeTech 6205 Combined Bathymetry and Side Scan Sonar for Storm Response Hydrographic Survey

Howie Meyers
Directed Research Project

M.S. in Earth Sciences/Ocean Mapping

Friday, May. 17, 2024, 10:10am
Chase 130

Combined bathymetric and side scan sonars may represent an alternative to independent multi-beam echo sounders and side scan sonars for shallow water storm-response hydrographic survey. The Atlantic coast of the United States is dominated by shallow sand and silt bottom coastal and inland water areas prone to shoaling and other navigational hazards, especially after major storms. In the aftermath of such storms, areas of high navigational significance are typically technically challenging and dangerous areas for hydrographic survey teams to operate vessels. The historical limitations of phase differencing systems are generally well documented, however recent developments in combined bathymetric and side scan systems may offer hydrographers an improved survey tool for meeting strict hydrographic standards and declaring storm-impacted waterways safe for navigation. Phase measurement offers significantly greater angular coverage, allowing survey vessels to maintain safer distances from pier faces, large vessels, and charted dangers to navigation. Increased transducer receiver elements derive a higher number of phase measurements which may increase data density at nadir, as well as increase accuracy of bathymetry points and limit multipath effects. Full bathymetric coverage and co-registered side scan data allow for the confirmation of seabed features that would pose navigational risk to mariners. As identifying and reporting these dangers to navigation are a vital part of the storm response survey, the ability of the latest generation of combined systems to reliably detect and measure accurate least depths of discrete seafloor targets needs be investigated. Further testing must be performed to determine the current state of technology and whether PDBS systems warrant new consideration for NOAA nautical charting hydrographic survey. In this investigation, the object detection capabilities of the Edgetech 6205 Combined Bathymetry and Side Scan Sonar are tested, and its utility and ability to faithfully record least depths on navigationally significant seafloor targets are discussed. 


Howie Meyers graduated with a B.S. in Geology from the College of Charleston and is currently pursuing a master's degree in Earth Sciences: Ocean Mapping. Howie has worked for the National Oceanic and Atmospheric Administration (NOAA) since 2017 as part of the Office of Coast Survey/Navigation Response Branch. He served as a Physical Science Technician aboard Navigation Response Team 2 (Fernandina Beach) until 2021, and now serves with Navigation Response Team 5 (New London) while working towards his M.S. at CCOM/JHC.