Hydrography is defined by the International Hydrographic Organisation as that branch of applied science which deals with the measurement and description of the physical features of the navigable portion of the Earth's surface and adjoining coastal areas, with special reference to their use for the purpose of navigation.

The Naval Hydrographic Department is a part of the Indian Navy and is a national facility which provides hydrographic information for the entire gamut of sea-related activities. It provides navigational charts, sailing directions, navigational information and warning services of mariners, data of demarcation of baselines for coastal regulation zones and a host of hydrographic data for coastal offshore engineering and marine scientific research. The Chief Hydrographer also serves as the advisor to the Government of India on hydrographic matters which include maritime development, international boundaries and demarcation of the country's maritime zones.

The National Hydrographic Department has produced 350 navigational charts and associated publication for safe navigation in Indian waters with the advent of digital technology. The department also undertakes various surveys for development of new ports or other coastal facilities towards preparation of navigational charts, engineering feasibility studies etc. The department also conducts internationally recognised training in hydrography. Thus, the Naval Hydrographic Department supports marien development together with naval security of the nation.

Information technology and its applications to hydrographic products and services have led two major developments in the world of hydrography. One is satellite based safety and updating service and the other is electronic chart display and information system (ECDIS). ECDIS is a cutting edge product of information technology applied to maritime navigation. It is an intelligent and dynamic information system designed to increase the safety and efficiency of navigation at sea.

The department has entered in the field of project surveys and is looking towards self-sustenance under economic liberalisation and evolving opportunities. National Hydrographic Office has bagged a number of prestigious survey projects. In addition, port organisations have also approached this office for surveys and other services in the field of hydrography.

The Government has recognised the importance of coastal zone management to check and streamline the development process along the Indian sea shores and has nominated the Chief Hydrographer as the demarcating authority for coastal zone regulation under the Environment Protection Act. This office has been undertaking surveys for coastal zone management for different agencies including the State Governments. The coastal zone management surveys will help the town planners to regulate the developmental acitivties in coastal areas.

On the international scenario, India is an active member of International Hydrographic Organisation, Monaco and represents various committees. The Chief Hydrographer to the Government of India is a member of the United Nations which deals with the technical issues of demarcation of maritime boundaries and member of the UN Commission which deals with the technical issues of demarcation of the continental shelf under a UN convention on the laws of the sea. He is also member of various national committees and projects such as Sethusamudram project, Navigational Safety Port Committee (NSPC), Space Application Centre Programme, Vessel Traffic Management Scheme (VTMS) and Marine States Development Council (MSDC).