Knowledge of sea bottom terrain is a crucial piece of information required in harbour rehabilitations, basin and access channel dredging, and the design of coastal structures such as breakwaters/ quays/ outfalls etc. Furthermore, accurate bathymetry data is the key for numerical modelling activities. Many clients seek LHI’s expert service in the hydrographic (Bathymetric) surveys for its unblemished reputation in conducting the surveys for accurate and fast production of bathymetric maps.

LHI also undertake river cross section and longitudinal surveys, and even profiling of reservoirs.

Echo sounder coupled with Global Positioning System (GPS) and a state-of-the- art Navigational software mounted on a robust survey vessel is utilised for bathymetric surveys.


DGPS - Trimble DSM

  • 10 Hz (10 positions per second) output rate
  • 12 GPS Tracking channels
  • Real-Time DGPS Sub Metre Accuracy


  • HydroPro Software

Echo Sounder – Odom (Hydrotrac)

  • Operating Frequency : 200 KHz
  • Minimum Recordable Depth : 0.2m
  • Maximum Recordable Depth : 600m
  • Accuracy of Measurement : 0.01m (+/-0.1% )
  • Beam Width : 4