Bathymetric Survey

In association with Sea Shadow Global Survey Solutions and Amaza Surveys, Bridge Maritime conducted a hydrographic survey of the slipway and seabed approaches to NSRY Station 6 slipway in Gqeberha. Through this survey, we identified and determined the current bathymetry, underwater slipway slopes, debris, and the condition of the slipway and its vicinity for construction planning purposes.

To support the valuable work the NSRI does every day, we were delighted to provide this service free of charge. The NSRI is a voluntary non-profit organisation, and it was our pleasure to assist them in their efforts to save lives in South African seas.

The survey was conducted by two of our professional industry experts, Timothy Sean Cullinan and Gaynor Deacon. Together, the duo boasts over 60 years’ combined experience in various marine and marine construction projects. Cullinan handles the bathymetric and topographic data acquisition, system mobilisation, installation and configuration; while Deacon conducted the post-processing, QA/QC analysis and compilation of the interpretive report.

Using a local vessel of opportunity, we loaded our comprehensive systems aboard with a made-for-purpose pole mount, using a GAMS calibration to calibrate and verify all measured offsets. Our equipment included a LEICA GS14 RTK GNSS base and rover, a Norbit iWBMS high-res multibeam mapping system with GNSS, a Norbit AML Bse X2 profiler with GPS and WiFi, Norbit DCT acquisition software, Beamworx NAVAQ, AutoPatch and Autoclean hydrographic software, and an online 3D asset Management software.

The Norbit iWBMS is a portable all-in-one tightly-integrated broadband multibeam turnkey solution, which provides high-resolution bathymetry over a wide swath. The compact system allows for fast and reliable mobilisation with minimal errors from lever arms and offsets, and has been proven globally to deliver the highest quality sounding for surveys in all conditions.

Over the course of 1 day, we covered an area of around 2 hectares. Several items of interest were observed, including tyres, beams and other objects near the slipway. All in all, we identified over 60 areas of interest to be considered when planning future construction.

All surveys were conducted according to the internationally-recognised IHO Standards for hydrographic surveys.