Ashtead Tech Provides Sonar for Furgo’s Survey

Ashtead Technology has supplied Edgetech 6205 interferometric sonar to Fugro for the acquisition of imagery and bathymetry data while surveying the San Francisco Bay.

By mounting Edgetech 6205 sonars to Fugro’s M/V Locator and M/V Julie Ann survey vessels, Fugro surveyed 422 square kilometers of the bay. In addition to 550-kHz sidescan sonar imagery, each survey line also acquired swath bathymetry that was gridded at a 25cm resolution.

The California Ocean Protection Council (OPC) contracted Fugro to survey the San Francisco Bay with the aim of providing up-to-date, accurately positioned sonar imagery to aid the delineation of marine habitat maps, as required for the California Seafloor Mapping Program. The National Oceanic and Atmospheric Administration (NOAA) and OPC required swath bathymetry throughout the bay area. The combined survey data will not only support OPC’s habitat mapping goals but will also assist NOAA’s mandate for port and harbor maintenance, coastal engineering, and coastal zone management.

The majority of the San Francisco Bay survey has shallow water, less than three metres in depth, and the muddy water precludes the acquisition of airborne bathymetric LiDAR and reflectance imagery. Fugro with its clients developed a survey plan that would overcome these challenges to capture the data required.

Shaun Neumann, Technical Sales Manager for Ashtead Technology in Houston said: “We were pleased that Fugro turned to us for the provision of this advanced survey equipment. We are continually investing providing access to the latest technologies on the market. The 6205 sonars were perfect for the job, providing highquality imagery and wide swath bathymetry simultaneously. The sonars performed extremely well in shallow, choppy and muddy water.”