Construction topographic survey, also known as topographic survey, is the activity of researching and evaluating natural conditions on the ground at the proposed construction site to serve the planning, design, and calculation of excavation and embankment volumes of the project. In addition, for important projects, during the construction and exploitation of the project, it is also necessary to monitor the displacement, subsidence and tilt to assess the level of stability and take timely remedial measures if it exceeds the allowable limit.

Hydrological survey (also known as hydrogeological survey) is the activity of collecting and analyzing all relevant information about the water environment, including measuring water levels, flow rates, water volume, and water temperature. These data are important factors in predicting hydrological phenomena such as tides and floods. In addition, hydrological survey data is also used for the purpose of designing underground water systems. Based on that data, survey and construction units will have the most appropriate exploration, inspection and construction methods for each different project.