Once a building or parking lot is built the rainwater will run off that property at a much faster rate, affecting everyone downstream. If the run off is not controlled it will cause flooding. Look in the roads and parking lots the next time you are in a rain and it is obvious which sites were developed by an engineer who had a good topographic survey furnished by a surveyor.
This type of survey is used to determine the elevations throughout a piece of property. A surveyor locates the physical features that exist on site, including natural features such as trees and streams, and man-made features, such as buildings or roads and provides vertical information with the relative heights of the ground and other identified features. A topographic survey is usually used for engineering studies, landscaping projects or construction planning.
A topographic survey is the beginning of almost any engineering project. Without this survey an engineer has no way to tie his concept to the land on which the project will take place. A surveyor uses different survey methods to locate all natural and man-made features. These features are given elevations based off of a vertical datum and coordinates based off of a horizontal datum. This information is then used to model the surface and generate contours lines. Contour lines enable one to manipulate the existing site to sustain the proposed concept and make the final product one that will be friendly to the developer and the environment.