Topographic Surveys – What is a Contour Line

by | Oct 18, 2018 | Surveying Related

The data that a surveyor obtains when performing a topographic survey can be shown in a series of lines called contour lines. The proximity of these lines to one another is a direct correlation to the “peaks and valleys” that occur on the property.  Here is some information and examples on to how contours appear vs. what is happening on the ground.

  1. Gentle slope: the more gentle the slope, the further apart the contour lines will appear. The dark black line on the left image represents the road shown on the right image.

  2. Steep slope: the closeness of the contour lines represents a steep decline/incline.

  3. Hill contour: the top of the hill is the highest point and is hence the center of the circle rings as shown below. As you walk down the hill, the contours spread out as the base of the hill is larger than the peak of the hill.

These generic sketches are an example of what a Topographic Survey will show.  It takes the results of a 3-D world on a 2-D sheet of paper.  The more data the surveyor collects, the more detailed the topographic survey drawing will be.