AbstractHYDROCAD (HYDROgraphic position fixing through AutoCAD) is a low-cost and powerful microcomputer-based hybrid digital processing system for conventional hydrographic surveys in near and inshore waters. The system was designed for implementing the digital hydrographic charts in AutoCAD, ade factostandard in microcomputer-aided design and drafting (microCAD) system in the engineering industry. Its purpose is to allow engineers ready access into the digital files for designs of near and inshore structures. Implementing the digital charts in AutoCAD integrates the activities of the hydrographic survey office and the engineering design office.HYDROCAD recycles the product life of existing analogue position fixing and echo-sounding systems.