How you can get a sneak peek in the Adelaide St bus and Metro tunnel

Services will begin in the new Adelaide Street bus and Metro tunnel in just four weeks – and we’ve gone underground to show you what it looks like. But you can also have your own sneak peek later this month.

Brisbane Lord Mayor Adrian Schrinner described the new Adelaide Street tunnel as the “biggest boost to underground infrastructure we’ve seen since the Queen Street bus station”, which was built for Expo ’88.

He said the new tunnel would take a lot of pressure off that bus station, “which does a lot of the heavy lifting”.

More than 1400 bus and Metro trips will traverse the 213-metre tunnel each weekday, which the council promises will reduce congestion in the CBD and create capacity for more services.

Schrinner said that would mean higher frequency and better reliability.

“Delays in the network hold people up, and they make public transport less attractive for people to use,” he said.

Once the tunnel opens, Metro frequency could be increased from the existing five minutes to four, then three, he said, adding that would be based on demand.

“So, as the number of passengers grows, and as we have more Metro vehicles arriving – the fleet order is still coming in – that will allow us to gear up,” Schrinner said.

“So, ultimately, the discussion between Translink, the state government and the Brisbane City Council will determine when we move to the higher frequencies.”

The Adelaide Street tunnel is part of the Brisbane Metro project, which was first proposed by former lord mayor Graham Quirk in 2016.

More than 1000 bus trips per week will be removed from CBD streets into the tunnel for their outbound journey, with George and Turbot streets to benefit most.

The tunnel will provide a connection between North Quay and King George Square station, linking the Inner Northern and South East busways.

It will be used by the M1, M2, 222, 333, 444, S744, and the 61 southbound route, plus the 330, 450, 453, 454 and 460 northbound routes.

During the school holidays on Wednesday, September 24, members of the public will be able to walk through the underground busway as part of a community open day ahead of the first services on Monday, September 29.

The event will include seven sessions between 10.30am and 2pm, with live performances by the Paradiso Strings ensemble.

This will be the public’s only chance to experience the tunnel before it opens as a busway, with registration essential and open here.

Joel Miller, from construction company Acciona, said the soil conditions, being so close to the surface, and ensuring power and water remained on for nearby businesses made the tunnel a complex project. The use of excavators rather than a boring machine also added to the difficulties.

Ten weekends of testing in the Adelaide Street tunnel, including heat and smoke tests to check control systems, were completed late last month.

More than 3.424 million trips have been taken on the Metro electric bus services since it launched and replaced bus routes, including the 66, 111 and 160.

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