Road workers seem wooden

The mystery of the plywood people has been solved.

Contractors building the $850 million Transmission Gully motorway have revealed why human cut-outs, with hi-vis colouring, have appeared at their worksite in Kapiti, near State Highway 1.

The wooden figures have popped up in the middle of earthworks forming the northern tip of the motorway.

Project director Boyd Knights said the plywood people were acting as markers for vehicle operators working inside an area of sand dunes just south of MacKays Crossing.

Much like farmers use scarecrows to protect crops germinating below ground, the figures alert machine operators to equipment under the work area, he said.

The cut-outs protect devices called settling plates that measure pressure from sand loaded along the path motorway.

‘‘It literally drains moisture from the soil below the new road embankment and compresses it,’’ Knights said.

Workers scoop up nearby sand and dump it along the road, adding pressure on the soil below.

‘‘Having these human-shaped warning markers ensures workers and vehicle operators avoid the area, just as they would if there was a real person present.’’ of the four-lane