What is a Line of Sight Analysis?

A Line of Sight Analysis is a special type of topographical plan usually prepared for an entrance permit for a new driveway access or widening. Its purpose is to show how far a vehicle entering a road from a driveway can be seen by travelling motorists.

The project starts with a field visit to measure the road details up to several hundred metres on each side of the proposed access location. Then, based on the height of a car we calculate how far a vehicle entering the roadway can be seen by an approaching motorist (before the approaching car disappears behind a hill). Finally we compare this distance to the stopping distance of the approaching vehicle. If the design speed of the road is high- a longer stopping distance is required, therefore a longer sight distance is required in order to approve the entrance permit.