The field which measures and describes the attributes that affect offshore oil exploration, dredging, marine construction and marine navigation is Hydrographic Survey. Hydrographic Surveys are carried out in line with International Hydrographic Organisation's specifications.
Special Publication No. 44 to obtain information on water depths in:
It requires safe navigation, project-cum-engineering, irrigation, tidal power, tourism, inland water ways, pre-dredging, progressive and post-dredging, siltation, erosion, pollution, flood control etc. The bathymetry data is acquired using high accuracy DGPS system, Single Beam Dual Frequency Echo Sounder and MultiBeam echo sounder.