CGC Dredging is a specialist dredging company based in Western Australia that has expertise in mine tailings and marine dredging industries. With operations beginning in 1980, CGC is extremely experienced and well-respected in the industry with an established fleet of small to medium-sized cutter suction dredges.
Port Geographe, located in Western Australia, is a canal community and small boat harbour that requires regular dredging in order to cut back seagrass wrack and accumulated sedimentation collected on the seafloor. Dredging work establishes appropriate depths and keeps the channel open to navigation. In addition, the port’s seawall structure had to be redesigned because it collected unmanageable levels of seaweed and sand. CGC was tasked with dredging the footprint to desired depths to prepare the seafloor for placement of rock for the new seawall. With a tight deadline and specification to meet these goals, CGC turned to its technology partner SITECH Western Australia (WA) and Trimble, USA, for assistance.
The CGC team adopted the Trimble HYDROpro Construction software, Trimble SPS461 GPS heading and positioning receivers; Western Australia breakwater and seawall construction company WA Limestone (WAL) used Trimble GCS900 Machine Control on its excavators and an SPS855 receiver with HYDROpro Navigation on a Trimble Site Tablet and a single beam echosounder on its hydrographic boat.
The benefits of this setup were as follows:
- For the hydrographic survey, WAL avoided a multi-beam scanning operation that was well over budget.
- For CGC, precise cutter head guidance allowed the dredge operator to dredge to the desired depth and return to the exact location where the previous day’s work ended; this avoided the wasted time and costly rework.
- HYDROpro software displayed the precise position of the cutter head underwater within an accuracy of ten centimetres.
- Met depth guidance parameters and rigorous design measurements.