Transit NZ has quietly switched off for the holiday period new on-ramp traffic signals it installed before Christmas on Auckland's motorway network.
The signals, aimed at feeding traffic more efficiently into mainstream motorway lanes, were commissioned a week before Christmas as new links were opened on Spaghetti Junction.
They have been installed at sites such as the new links from the Northwestern Motorway and the port to the Northern Motorway, and on on-ramps from Wellington St and Curran St.
Transit chief executive Rick van Barneveld said at an opening ceremony on December 15 for the motorway junction's $207.5 million refit that the signals would be essential for managing northbound traffic through the bottleneck on the Victoria Park viaduct, and he appealed to Aucklanders to work with his organisation to get used to the new system.
"Our commissioning over the Christmas period is a crucial time for the region to do that, when we don't have peak traffic flows," he said then.
But although the signals appeared to work with little difficulty for the first week on the new Northwestern to Northern motorway link, they were not operating as a long line of vehicles queued back from the ramp at lunch-time on Christmas Day to join traffic crawling along State Highway 1 to the Harbour Bridge.
Transit has since disclosed that it does not have enough operators rostered over the holiday period to monitor the new signals, even though traffic bulletins posted on its website continue to warn motorists to take care when approaching them.
It does not intend switching the signals back on until January 8, when commuter traffic will start building after the holiday break.
The signals do not need human intervention to work, as they turn themselves on and off according to traffic volumes detected by sensors embedded in the road.
But Transit has promised to monitor them closely in case traffic queues back too far into local streets, in which case it is bound by a memorandum of agreement with local councils to re-adjust or switch off the signals.
Despite the minimal apparent impact on traffic flows from the Northwestern Motorway during their first days, the Herald published a letter last week from a reader who claimed the signals on the Wellington St on-ramp were creating unacceptable queues.
"What was a free-flowing area a few days ago has become chaos," wrote North Shore City resident John Kania. "Union St and Wellington St are now clogged with long, slow-moving queues," he said.