ESL are providing construction survey services both on land and across Victoria Harbour. We are providing survey management, site land surveying and hydrographic survey services.
The major part of this contract involves the construction of an immersed tube tunnel with landings and a ventilation building.
Survey work includes set out for construction of Immersed Tube units, Trench dredging, land cofferdam and a ventilation building.
Hydrographic surveys (Swath Bathymetry) are carried out on a daily basis to check dredging, gravel spreading and backfilling operations and ensure no adverse impact on the nearby cross harbour tunnel. A quick turnaround is vital with sounding plans and isopachs provided within 12 hours of survey completion.
Amongst our specialist services ESL have set up a GNSS base station at Hung Hom using Trimble receivers configured to receive GPS/GLONASS/BEIDOU and GALLILEO signals providing +/-10mm horizontal and vertical accuracy across the harbour.