Sydney metro

Year:Opening 2019

Duration:5 years and counting

Cost:£4.5bn

Country: Sydney, Australia

What did this project achieve?

Create Australia's first underground metro system using state-of-the-art operating systems

Sydney Metro is Australia's biggest public transport project. Currently under construction, it will be a 66km fully-automated railway system with 31 stations.

Stage 1 of the scheme, Sydney Metro Northwest, is 36km long. Set to open in 2019, it will run from Rouse Hill – a suburb in the north west of Sydney – to Bankstown in the south west of the city. The line will run 15 trains an hour at peak times.

Stage 2 of the project, Sydney Metro Northwest, will be an extension of the stage 1 line. It will run under Sydney harbour through a series of new underground stations past Bankstown in the south west. The line is expected to open in 2024.

Stage 2 includes twin tunnels which at 15.5km long are the longest in Australia, 8 new stations and an upgrade of existing lines.

The new metro will have a target capacity of 40,000 passengers an hour, nearly double the 24,000 passengers an hour carried by Sydney's current suburban system.

The network will have real-time train information at stations and a range of connected phone apps and other technology to help passengers plan their journeys.

The scheme should increase passenger capacity by 60% when it's completed in 2024.

Difference the metro will make

Sydney Metro will connect the city's central business district to the growing north west region of the city. Commuting should be easier and faster for thousands of the city's workers.

The scheme should boost the local economy and encourage businesses to move into Sydney from other areas of Australia. Improved transport may also bring in overseas investment.

The new railway should also reduce traffic congestion on the city's roads.

How the work is being done

Around 5,000 people are working on the Sydney Metro scheme – almost 400 of these are tunnellers.

Five tunnel boring machines (TBMs) are being used as part of the project. One of these is a special TBM adapted to dig under Sydney Harbour. The 120m-long machine weighs 900 tonnes.

The harbour TBM is fitted with high strength alloy steel discs on the cutter head at the front of the machine. The crushed rock is scooped onto a conveyor belt and carried back, away from the head.

The TBM uses fluid to turn the excavated rocks into slurry – a semi-liquid mixture. The slurry is then pumped into a pressurised chamber in the TBM. From there, it's pumped to barges on the surface of the harbour for removal.

The tunnel wall is lined with pre-constructed curved concrete segments. Engineers put the circular tunnel wall together using a special vacuum lifting device.

Once the tunnel segment is assembled the TBM moves forward about 1.7m and the process starts again.

"​‌

A once-in-a-generation project that will transform the rail network in Sydney.

Joe Barr

CEO of John Holland, one of the companies building the metro, speaking to Business Insider Australia, June 2017.

Fascinating facts

The new metro won't have a timetable though commuters are being told there will be a train every 4 minutes. Metro bosses are predicting a '98% on time running reliability.'

The system aims to move more people across Sydney Harbour at peak times than the Sydney Harbour bridge and Sydney Harbour tunnel combined.

The ultimate goal for the network is to run a train through the centre of Sydney in both directions every 2 minutes – a frequency of service not yet seen on the city's commuter railways.

People who made it happen

  • Client: New South Wales government
  • Stage 1 construction: engineering companies CPB Contractors, John Holland and Ghella

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