Surveying is one of the oldest professions, dating back nearly 3,000 years ago in ancient Egypt. It can be described as a profession, science or technique for determining a certain position in three dimension of either natural or man-made feature on or beneath the surface of the Earth. It is only performed by licensed surveyors. These professional have specific tools for surveying which include optical instruments for measuring angles horizontally and vertically from the survey station, a level to establish heights, a plane table for establishing the locations of points on the ground relative to a baseline, barometer, total station, ground-based laser scanners and handheld computers. Those tools for surveying help determine land boundaries which are shown in digital form or on maps, charts and plans. For instance, before building a highway, road, building, determining land boundaries is recommended.
Even though mostly required at construction sites, tools for surveying are also used in:
- Land surveying
- Cadastral land surveys
- Topographic surveys
- Geodetic surveys
- Engineering surveying
- Deformation surveying
- Hydrographic surveying
Also, depending on the job or industry, there are different surveying techniques.
Tacheometry – Tacheometry is a technique for quick surveying of horizontal distance and vertical elevation of a point without using modern and sophisticated technology. Although it is considered less accurate, it is very practical in topographic mapping for regions that have no access to modern technology.
Triangulation – Triangulation is a technique of determining a certain position by measuring angles in a triangle formed by a series of fixed points or stations, overlapping and joining each other. Triangulation is the most efficient in the land surveying because it minimizes the number of various needed measurements.
Leveling – Leveling is performed when elevating fixed point using leveling instrument to move on a certain area.
Trilateration – A similar technique to triangulation is trilateration which uses same principles. This technique supports electronic distance measuring equipment, unlike triangulation. Also, trilateration is easier to perform, provides faster mapping, requires less tools, and is cheaper. It can determine a general location in no time.
Traversing – Traversing is one of the most difficult to perform. It requires predetermined and measured distances and lengths to connect them together at various points to determine the right location. This techniques finds its use when surveying for new railroads, highways or roads, or other similar linear projects.