A topographic survey determines the location of natural and man-made features (such as buildings, improvements, fences, land contours, trees, streams, etc.) of the land along with its elevations. This type of survey may be required by a government agency but it is mostly used by engineers and/ or architects for the design of improvements or developments on a site.
In other words, a topographic survey or contour survey provides you with the exact figures of the size, height, position of the different changes that have occurred in course of time with regard to their presence of their natural existence. Sometimes, these surveys are also used for the formulation of an optimal plan for drainage, ditches, grading and other features.
Topographic surveys are generally conducted before handing over the ownership of the land or even when the property owner/ industrial owner is intending to make some alterations in the land. In these types of surveys, the main focus is on the distance from the ground rather than the horizontal measurements.
A topographic map is used to depict terrain relief showing ground elevation, usually through either contour lines or spot elevations. The map represents the horizontal and vertical positions of the features represented. The scale of the topographic survey will conform to the needs of the client. A smaller contour interval will result in more field measurements and higher cost.
Topographic mapping is much more efficient and accurate today because of advances in survey techniques, instrumentation, design and printing technologies, and the use of aerial photography and satellite data. Today it is possible to make 3D topographic digital and interactive maps that show the entire landscape roads, mountains, rivers, buildings in amazing detail. This data can be used in AutoCAD programs, which is in turn is worked upon by the engineers and thereby you can easily have the view of how the topography will change after the planned changes.
A topographic survey comprises horizontal and vertical plane surveys. It can be carried out using a variety of techniques. Some popular techniques include:
Topographic surveys are vital for architects, developers and land owners, as they require accurate, three-dimensional representations of the land.