Control Survey in Toronto

What was needed

Later survey work needed a common framework: fixed, coordinated reference points that following measurements could tie back to. Setting that control first keeps measurements taken on different days consistent with each other.

The surveying work we carried out

• Established field control at a residential intersection, so that later survey work could tie back to the same coordinated points
• Set up a robotic total station on a tripod at the street corner, beside a brass survey control disc in the road surface marked with paint

Site conditions

Our site photos show a residential street corner with painted crosswalks, cracked and patched asphalt, a concrete sidewalk and curb, mature trees, houses close to the street, overhead wires and cars parked along the curb. The equipment cart and instrument case were kept at the edge of the sidewalk beside the setup.

Methods and equipment

The work was carried out with a robotic total station on a tripod, with the equipment moved on a cart and kept beside the setup at the curb.

How survey control supports later work

Control is the reference framework for a project. Once points are coordinated and checked, topographic surveys, layout and as-built checks carried out later can all be tied to the same points, so measurements from different visits agree with each other. Control does not replace those surveys; it underpins them.