Originally, the majority of the hydrographic surveys had been conducted by civilian fishing vessels which had additional scientific equipment, naval and governmental crews on board. However, since the Chinese economic reform, and the depletion of the fishery resources, the civilian fishing vessels must venture much further out into open ocean on extended voyages, thus were no longer available for coastal or inland water survey operations.
In the past, most hydrographic surveys were conducted by civilian fishing boats that had scientific equipment and crew members from the navy and government. However, since China's economic changes and depletion of fishery resources, these vessels now have to travel much farther into the open ocean on longer trips, making them less suitable for surveying coastal or inland waters.