Hydrographic Surveying

Knowing the seabed topography is a prerequisite for safe navigation. Acquisition and collation of the bathymetry data form the basis of nautical chart production. Such data also facilitate other purposes such as port planning.

Hydro 1

First Commissioned: Aug 2019
Length: 15.0m
Breadth: 4.5m
Draught (full load): 1.7m
Maximum speed: 18 knots
Crew: 3

Hydro 2

First Commissioned: Dec 2023
Length: 24.9m
Breadth: 10.2m
Draught (full load): 2.5m
Maximum speed: 18 knots
Crew: 4

Hydro 3

First Commissioned: Dec 1998
Length: 7m
Breadth: 2m
Draught (full load): 0.8m
Maximum speed: 20 knots
Crew: 2

Survey Equipment

1) Dual-head Multi-beam Echo Sounder on ‘Hydro 1’

Specification

Operating frequency : 200kHz to 400kHz
Number of beams : 1024
Beam width : 0.5°@400kHz across track, 1°@400kHz along track

Dual-head Multi-beam Echo Sounder on ‘Hydro 1’

2) Dual-head Multi-beam Echo Sounder on ‘Hydro 2’

Specification

Operating frequency : 200kHz to 400kHz
Number of beams : 800
Beam width : 1°@300kHz

3) Single-beam Echo Sounder on survey vessels

- is a simple and reliable electronic sounding device engaged in close shore sounding surveys and provides quality check to the sounding data acquired by using multi-beam echo sounder

4) Motion Sensor

- is a highly accurate electronic sensor used to determine the effects of vessel movement such as ‘roll’, ‘pitch’ and ‘heave’ during field operation for data post-processing

5) Sound Velocimeter

- is a useful tool in hydrography to provide sound velocity at different water depths so that the deviation of transmitted sounding beams due to variation of sound velocity in water, can be compensated during data post-processing