Land Surveying: 3 Interesting Ways To Measure The World

Have you ever driven down the road and seen a few guys, each with a yellow tripod, several meters apart doing what appears to be staring at each other?  Occasionally, you'll see one looking through a contraption that could resemble a camera if you looked quickly enough.  Have you ever wondered what they're doing?

This seemingly odd behavior is actually a science called surveying.  Basically, they're taking 3-dimensional measurements of the land to determine distances between certain points and in some cases elevation.  Surveying has many different uses from determining land boundaries to creating maps.

There are a few different techniques of surveying that can be used.  Here are three of the more interesting methods:

Aerial Surveying
Also known as photogrammetric mapping, these are very high resolution photos taken from above to show contours, makeup, and conditions of a particular area of land.

If you've ever seen a map drawn in such a way that it almost looks 3-dimensional, you've seen the product of aerial surveying. A plain map would just be a 2D image of the land, but through surveying, shading can be added to project a sense of height or depth. 

3D Laser Scanning
High definition surveying seems at first a bit similar to aerial surveying, but it's much more different. Instead of using photographs taken from above, the ground is actually scanned point by point and a very precise digital representation is created. The contours of the land are fully and exactly represented. This can be done either from the air or on the ground.

This 3D model can then be used to do any type of spatial analysis needed for the project without the need to return to the surveyed site again. This makes planning much more efficient because everything necessary for the planning is stored in a computer.

Electronic Measuring
The fellows in the yellow jumpsuits with their odd yellow "cameras" are using the surveying technique of electronic measuring. This uses beams of light between two theodolites (the "cameras") to precisely measure distances between two points and the angles between them.

Using this technique, surveyors can measure across areas that would otherwise be very difficult to measure like valleys, swamps, and marshes. Through electronic measuring, they don't actually need to be in the valley itself to be able to measure how big it is and what the different angles of the land are.

Why is surveying useful?
One of the most common purposes for land surveying is to delineate boundaries between properties. Often municipalities will use surveying to determine where a new store can be built, where a change in the road pattern should go, or how they'd need to work a piece of land to be able to complete their building or road project.

Other uses are for generating maps of large land areas, monitoring land conditions over time, or being able to have a 3D-rendered image of an area so that it's much easier and less expensive to study it. 

We have all benefitted from and used products of the science of surveying; we might have just not realized it! Think about that the next time you see those chaps with the odd cameras!

Aerial surveying & photography is slowly gaining popularity as one of the most effective ways of land surveying. It is one of the most technologically advanced land surveying methods, which provides precise and accurate results. Click here to know more.