Spaghetti junction’s opening ‘most difficult’ of WestConnex projects
The opening of a $3.9 billion spaghetti junction beneath inner Sydney to motorists within the next two months is the most challenging of all the WestConnex toll road projects, the state’s transport agency says.
Ahead of a December ribbon cutting for the Rozelle interchange, a 235-metre road bridge over eight traffic lanes of the City West Link and a four-way intersection will open to vehicles. It will link The Crescent in Annandale to Victoria Road and the Anzac Bridge.
The Crescent overpass will open in coming weeks.Credit: Nick Moir
The Crescent overpass opening has been staged ahead of the underground interchange to give time to motorists to get used to the road changes. The interchange is the final and most complex part of the $17 billion WestConnex project.
Transport for NSW’s infrastructure and place deputy secretary, Camilla Drover, said the Rozelle interchange was more complicated because it connects to a raft of motorways including the M4 East, the M4-M8 Link, the City West Link and the Iron Cove and Anzac bridges.
“It doesn’t have one start and one end,” Drover said. “The connection into those operating motorways is something that obviously needs to be very carefully considered.”
Australia’s most complex motorway project comprises 24 kilometres of tunnels beneath Rozelle and Lilyfield, about seven kilometres of which will mostly be used for ventilation.
The so-called green link bridge near the Crescent overpass will provide a pedestrian link between parkland above the interchange and Annandale.Credit: Nick Moir
The interchange’s systems have to be tied in with other motorways that make up WestConnex, which is managed from a control centre at St Peters.
“When we opened the M4 East we were just turning on its standalone operating system,” Drover said. “But as we’ve added more sections with time, the need to integrate with them all has grown.
“All their operating systems have to control their own discrete part, but also seamlessly integrate with the whole of WestConnex, so it operates as one system, and that’s complicated.”
Roads Minister John Graham said an adjustment period for motorists always occurred after motorways opened, and the transport agency would monitor traffic and introduce measures in response to traffic flows.
“We’ve been telling motorists since August that we are going to see delays along Victoria Road when the Rozelle interchange opens,” Graham said. “This will particularly impact commuters from western Sydney who are trying to access the city via the Anzac Bridge.”
A so-called green link bridge near The Crescent overpass and three exhaust stacks will provide a pedestrian link between a 10-hectare parkland above the interchange and Annandale on the other side of City West Link. The parkland will be open in December.
With testing and commissioning still under way, Drover said motorists would still encounter some disruption until the interchanged opened. “There will be changes, and with changes come network uncertainty and disruption,” she said.
A worker walks through one of the Rozelle interchange’s road tunnels.Credit: Jessica Hromas
“We always see network disruption when you put a new asset into the network, particularly something of this scale, and it is the last stage of WestConnex.”
However, Drover said it would be easier for motorists to navigate the interchange than explaining it because vehicles would enter at one point and exit at another point by following signs. “It’ll be quite legible for motorists,” she said. “It probably looks more complicated when you see it in 3D model.”
Construction of the interchange has required dozens of lane changes – referred to as “traffic switches” – to the City West Link and other arterial routes over the past four years.
West Ryde resident Ron Pitts, who travels through Rozelle most days, said he was concerned about recent changes to lane markings where Victoria Road connects to the City West Link and the Anzac Bridge because of the way they bear sharp diagonally left into another lane. His wife was involved in a minor car accident near the intersection last week. “I have seen two near misses myself,” he said. “It’s just mad, the way they have got them.”
But Transport for NSW said the temporary markings at the intersection had since been altered to ensure the left-hand turn was not as sharp as it had been to make it safer.
As part of planning conditions imposed on the project, the interchange’s impact on the motorway network will be assessed a year after it opens, and then at the five-year mark.
Underscoring the interchange’s complexity, the state’s transport agency took control of the project in 2017 from a corporation set up to oversee WestConnex after only one bid from contractors to build it was received in the initial tender process. The interchange was also separated from construction of the M4-M8 Link, which opened in January. It left the government bearing the risk of delivering the interchange.
Drover said the complexity was highlighted by the fact that the project comprised kilometres of tunnels, and some large underground caverns. “It’s complicated,” she said. “We’ve got 40 locations where the carriageway and the ventilation tunnels cross each other on the project. And we’ve even got Metro West tunnels passing beneath the interchange as well.”
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