Have you ever gone out to your driveway, looked at your fence, and seen a small square reflector tacked on with a nail? It can be hard to notice, but once you see it you may start to ask yourself: What is that? If you have just noticed that on your fence post, worry not. It is not a practical joke or a spy device. The object in question is likely a survey target.
Let us explain what it is, why it is there, and how it plays a silent, but vital role in your neighborhood’s infrastructure.
A survey target is a small reflective maker that is used by land surveyors. They use it when they want to identify precise locations when mapping or constructing. Survey targets can be reflective or adhesive stickers. They can also be nailed on targets through a stake process. This is always done with either crosshair-visible or reflective surfaces. Surveyors use two common devices when a survey target is present: total stations or drones combined with LiDAR. A reflective and/or signal from the survey target enables the total station or drone to identify the precise location.
In the image above, the square survey target marker on the fence post is a prime example of how considerate it is on the face of the marker. By its own size, the survey target is unobtrusive. They are always put on a feature where the surveyor has line-of-sight. Therefore, they must have intended for the target to be there.