The driver allegedly ignored three warning systems and drove his 5.1-metre high truck through the tunnel about 3pm. The tunnel has a height limit of 4.9 metres.

He allegedly drove about three-quarters of the way through the tunnel before stopping, damaging ceiling fans and overhead signs. The truck was not removed and the tunnel was not cleared until 7.30pm.

VicRoads told radio station 3AW the damage cost $1 million in lost productivity, based on a cost of $30 per hour per vehicle.

VicRoads spokeswoman Sally Pickering said later that a conservative estimate for the delays was $825,000, based on 5500 vehicles per hour being delayed in the Burnley Tunnel, Kings Way and Power Street.

‘‘The estimate is conservative because it doesn’t take into account other surrounding roads, therefore the overall cost would be in excess of $1 million,’’ said Ms Pickering.