Road and drainage set out

Road and drainage set-out surveys generally provide the set-out required for the designed horizontal and vertical alignment of a road or drain. Survey can consist of a peg or mark placed indicating an offset and level at incremental distances along the designed alignment. This information will determine the required cut/fill required, to meet the design criteria.

On green filed sites, road construction may begin with survey for bulk earth works, set-out would generally indicate the tops and toes of batters with cut and fill levels relative to the design. On existing roads and road upgrades new kerb and asphalt may be all that is required. In this case off set pegs or marks can be placed at incremental distances to determine the line and level of the designed kerb line required to be constructed. Pavement cut and fill levels sometimes may be required also if there is new asphalt to be laid or road profiling required.

Both road and drainage set-out generally will require as-built surveys to be carried out. This information can be used to calculate how close the road has been built to design, and if it meets the design tolerances and standards. Volumes of material used and required can also be determined from these surveys and are useful in accounting for materials used and also forecast what cut or fill volumes remains.