The mystery of how a height-compliant truck could somehow set off the sensors on the Sydney Harbour Tunnel this week has been solved by an eagle-eyed tunnel operator.
After reviewing the CCTV footage, the staffer discovered that it was a pigeon flying over the sensors at the exact same time as the 3.9m Western Star with its drop deck trailer that triggered the alarm.
Authorities were forced to shut down the southbound lanes of the tunnel for 20 minutes at 4.30pm on Wednesday, and were left scratching their heads as to the cause.
When they pulled out the tape on the slip lane before the tunnel, the truck measured just 3.9m, well under the height clearance of 4.4m, reported The Daily Telegraph.
The truck was finally allowed to leave an hour later after police had cleared it and was escorted across the bridge.
NSW Roads Minister John Graham later joked that the pigeon would likely get off with a warning.
“When the truck was measured as significantly under the height limit the incident became a mystery, and I want to thank the eagle-eyed tunnel operator who went back to the tape to discover the real culprit,” he said.
“On this occasion the pigeon will receive a warning rather than the usual 12 demerit points and six months off the roads — or above them in this case.”
Transport for NSW is due to file a report with Graham this month with a recommendation to either “operationalise” the work done by an over-height taskforce set up in mid-2023, and move to a business-as-usual footing, or continue on.