The national marine basic survey is a detailed seabed topography survey undertaken by the Korea Hydrographic and Oceanographic Agency (KHOA) under the Ministry of Oceans and Fisheries (MOF) to determine marine demarcation in the jurisdictional sea area and to lay foundation for development of marine resources based on scientific marine investigation for the nation’s Exclusive Economic Zone (EEZ). This project has been carried out annually since 2012.

This project is intended for the water depth survey, tidal observation, seabed image exploration, shoreline change survey, surface sediment survey, and identification of the characteristics of the seabed in the coastal waters of the nation, including the East Sea, South Sea, West Sea, and Jeju-do. Its aim is to clearly identify various maritime attributes, including navigational hazards.

The detailed port water hydrographical survey project entails the measurement and analysis of water depth, surface sediment, and navigational hazards in major Korean ports such as Gwangyang, Masan, Gohyeo, and Hadong, providing the basic data for supporting the development and management of ports, and the safety of vessels entering or leaving the ports.

This project is intended for providing the data necessary for marine policy decisions, such as improvement of aggregate collection systems and sea sand collection management measures, by conducting detailed surveys, including water depth measurement that aims to increase familiarity with seabed topography, status of surface sediments, and sedimentary layers affected by the collection of sea aggregates in the West Sea and South Sea (West Sea coastal zone, West Sea EEZ zone, and South Sea EEZ zone).

By conducting a detailed safety inspection of seawalls and drainage locks, analyzing the spatial data, and change of the regional seabed topography with the previous year's survey data through multi-beam surveys, It is a project that maintains and establishes continuous monitoring data to ensure stability, and has been conducted annually over the past 10 years.

After the Comprehensive Han River Development Project, hydrographic survey and measurement are conducted every year, and the results are analyzed, investigated and reviewed. The riverbed fluctuations are investigated during normal conditions, as well as flooding, and based on that, a comprehensive master plan is mapped out for control of the environmental status of the Han River, by building a database necessary for utilization and preservation of the data vital for the maintenance and refurbishment of the Han River and its tributaries.

The hydrographic survey aims to determine ideal locations for the installation of artificial reefs, and to obtain seabed topographic information, providing the basic data necessary for continuous maintenance.