Nestled in a historic art deco building,Rockpool and Spice Temple’s bars,restaurants and private dining rooms are destinations for corporate A-listers in Sydney’s CBD. In their exquisite interiors,staff go to great lengths to satisfy their wealthy guests.

Yet more than five years ago,a mega-rail project being carved out beneath their feet raised fears of disruption above. Large equipment excavating a temporary access tunnel to giant station caverns below risked causing vibrations and smashing expensive glassware in the bars and restaurants. The project team suggested Rockpool staff move glasses further apart. It averted disruption to Rockpool,but a few glasses in Spice Temple rattled from a sideboard and broke.

It illustrates the intricate work undertaken on a massive scale over the past seven years during construction of the$21.6 billion Metro City and Southwest rail line under Sydney Harbour and the heart of the city. In the north,the need to drill emergency cross passages between twin rail tunnels beneath Royal North Shore Hospital at St Leonards presented enormous challenges for engineers because of patient sensitivity to noise and vibrations around the clock. “The timing of those works and how they were managed and the respite period,just for those few cross passages,became a whole exercise in itself,” recalls Hugh Lawson,the Brit who has steered the mega rail project for the last seven years.

Concealed from prying eyes for years,the staggering scale of the new underground rail line will be unveiled on Monday when the line opens,in an act akin to unwrapping a giant present for the city. Carved out of sandstone,the fully automated railway is an engineering marvel that will reshape suburbs close to its stations and the way people traverse Sydney.

Yet,the mega project is about$10 billion over budget and the final piece – a 13-kilometre stretch from Sydenham to Bankstown in the city’s south-west – will be at least a year late opening. Critics fear that the new railway’s benefits will fail to match its eye-watering price tag,and are scathing of the project’s problem child:the conversion of the century-old Bankstown rail line into one for driverless metro trains.

Forty-five years after the opening of the last railway to be built under the Sydney CBD,commuters will be whisked at up to 100 kilometres an hour on single-deck trains between six new underground stations,as well as giant new platforms beneath Central Station. In a sign of the scale,the twin rail tunnels under the harbour and CBD span 15.5 kilometres from Chatswood to Sydenham. To ensure services run every four minutes in peak periods,the size of the fleet has been doubled to 45 trains,which are housed in giant rail yards in Sydney’s northwest and at Sydenham.

The new line forms the second stage of Sydney’s computer-driven rail network,acting as an extension of the Metro Northwest railway between Tallawong and Chatswood which opened in 2019. Together,the railway to beknown as the “M1” will extend 66 kilometres from Rouse Hill in the northwest to Sydenham in the south,and eventually onto Bankstown.

Global stage

“It’s the biggest city-shaping investment that has happened in 100 years and the community is yet to fully understand the impacts it is going to make,” says Rob Stokes,a former NSW planning and infrastructure minister who oversaw Sydney Metro before he quit state politics in early 2023.

To his mind,the new line is a bigger deal than the construction of the Harbour Bridge. Stokes argues that the bridge inevitability had to be built to link the city’s north and south,whereas the metro line was never guaranteed. “The metro is an entirely different way of conceiving how to develop the city,” he says. “The coathanger was transformative but ultimately inevitable. The metro is transformative but the decision to do it was never inevitable. It required many hard choices.”

After the final piece of Sydney’s Metro City and Southwest project opens late next year,the ribbon is due to be cut on anew metro line to Western Sydney Airport in late 2026,followed six years later by theMetro West railway under the city’s east-west spine between the CBD and Parramatta.

Costing $65 billion,Sydney’s metro network is one of the world’s largest rail projects,rivalling the 200-kilometre expansion of Paris’ rapid transit system. Known as theGrand Paris Express,the project will result in a railway encircling the French capital at a cost of €36 billion.

Blood on the floor

The triumph of opening a shiny new rail line risks overshadowing the long and rocky journey from attempts early last decade to revive plans for metro rail.

Several months before the 2011 NSW election,the then-head of the state’s transport agency,Les Wielinga,walked into a meeting with shadow transport minister Gladys Berejiklian who had asked to catch up. “I’ve got to admit,I was fairly nervous when I walked in. The[Coalition] policy was to put heavy rail out to the northwest. I believed that to be wrong,” he recalls. “It took until about six months after they got in for us to get the decision for cabinet to make it metro rather than heavy rail.”

In October 2011,Berejiklian first briefed new premier Barry O’Farrell on an option for a metro line instead of a railway for double-deck trains. Eight months later,O’Farrell and Berejiklian called a press conference tounveil a major shake-up of Sydney’s rail network. InSydney’s Rail Future blueprint,Berejiklian detailedplans in June 2012 for a metro-style,single-deck train system to the northwest,and an eventual second harbour train crossing. It was an abrupt U-turn on the Coalition’s election promise 15 months earlier to build a rail line to Sydney’s northwest as an extension of the existing double-decker train network.

The metro plans had been difficult to gain approval from inside government,and met deep cynicism from the media and the public after the previous Labor government’s metro plans were aborted. The internal rift was evident in the strain between senior Transport officials and Treasury bureaucrats over the blueprint’s wording. “There was a lot of tension as to whether it said ‘across the harbour’ or ‘under the harbour’,” recalls Peter Regan,a former senior Treasury official who is now Sydney Metro chief executive. “Treasury was certainly of the view that it should be above[the harbour],not below.”

Treasury’s fear was that tunnelling under the harbour would be more costly than building a line over the Harbour Bridge. “There was a massive kind of conjecture as to whether or not that was a credible thing to be building,” Regan says. “It was contentious because it’s a big call. That was a project way beyond what anyone had done for a long time. There was always a question mark around how it would get done,but also the timing and the dates.”

In the end,Berejilkian and transport officials prevailed:the blueprint envisaged a “new tunnel under the harbour”. Yet,it did not end the internal brawling with Treasury to turn plans for a metro rail line under the heart of the city into reality. “There was blood on the floor on a couple of occasions,” Les Wielinga recalls. “It’s a massive project. And it’s been built in some of the toughest construction environments you could imagine.”

It also ushered in a bruising period between the Berejiklian camp and Infrastructure NSW,an agency the new government had set up to advise on where and how to spend money on major projects. “[Infrastructure NSW’s] Paul Broad and Nick Greiner were very,very fixed on building the road network ... rather than rail,” Wielinga says.

In mid-2013,the well-regarded public servantretired due to health reasons. Wielinga left behind a tight team spearheaded by the northwest rail link project head Rodd Staples,senior Transport official Carolyn McNally,rail strategy head Gary McGregor and Berejiklian’s chief of staff Larry McGrath.

In the early days,the mega rail extension project was referred to as Sydney Rapid Transit,and for a time within top government circles was known as Crosslink,before it was publicly badged Sydney Metro City and Southwest. The Coalition government took small steps over several years towards revealing it to be a full-blown metro rail system,trying to avoid people drawing parallels with the Keneally government’s failedCBD metro rail plans.

In a sign of the sensitivities,public servants sweated over renders to be released showing how seats would be arranged in the metro trains. The first artist’s impressions showed rows of seats two abreast separated by an aisle. A later iteration revealed seats set against the side of carriages,while one row of seats faced forward. Eventually,renders revealed the real plans:seating along the sides of the carriages,meaning more passengers would stand. A six-carriage metro train has seating for about 378 people,compared with about 880 on a double-decker train.

Rodd Staples was both the key architect of the Metro Northwest line,and its extension from Chatswood,under the harbour to the CBD and Sydenham,and onto Bankstown. Under Labor,he had been responsible for delivering the$5 billion CBD Metro from Central Station to Rozelle – a project cancelled in early 2010 by then premier Kristina Keneally at a cost of about $400 million.

“Rodd had always pushed Metro,and he was always about getting a second network for Sydney,” former NSW transport minister Andrew Constance recalls. “I used to call him Metro Man. It was very much his baby.”

Staples traces the genesis of the new train network to 2006 whenDavid Richmond,who played a pivotal role in the 2000 Sydney Olympics,put the idea of a metro system on the table. “Labor can be credited with having been the genesis of Metro. What the Liberals were then able to do was convert that into reality and move it forward into delivery,” he says.

The money

Under new premier Mike Baird,the Coalition rolled the dice at the 2015 election,taking a political gamble in sellingNSW’s “poles and wires” power assets if it was voted back in. “That was the brave call. If that hadn’t gone through,and the community hadn’t given us the mandate at that 2015 state election,then this project wouldn’t be being opened,” Constance says.

The “poles and wires” sale,whichLabor opposed,delivered a $7 billion down payment to extend the metro line under the harbour. “There was no way in the world that we would have this project if that hadn’t happened,” Constance says.

Staples admits there had been moments until 2015 where he thought the project to extend the line might not eventuate. “If there’s a single moment where we went from a single line project to a network,it was that policy shift because it injected the money that we needed to keep the network expanding. Until then ... it could easily have been decades away,” he says.

In a cabinet reshuffle after the 2015 election,Berejiklian took the reins as treasurer from Constance who replaced her as transport minister. Later that year,Constance walked into a meeting of the powerful expenditure review (ERC) committee sporting an extensive business case and plan for Metro City and Southwest. “That was a very big moment. We got the tick off from ERC and got on with it,” he recalls.

Battle of Waterloo

By late 2015,the government had to make one of the project’s most fraught decisions:where to build a station on the southern stretch between Central Station and Sydenham. Berejiklian andConstance favoured Sydney University as the site while Stokes,Brad Hazzard and other ministers wanted a station at Waterloo to spur the renewal of a suburb dominated by public housing.

“The only contentious part of the project was Waterloo and the uni,and then of course the big decision in relation to poles and wires,” Constance says. “It was a tough,robust debate. But at the end of the day,a decision was made to put it at Waterloo to gentrify the area and uplift the social housing.”

With four ministers in favour of Waterloo and four for the university,the call was made by Baird as chair of the Cabinet infrastructure committee.

Stokes,who was the planning minister at the time,says it was lineball. “From a purely economic perspective,Sydney University was the logical route to take. But in terms of reshaping the city and providing social equity through public transport,Waterloo was the best choice,” he says.

Under early plans,a station at Barangaroo on the northern edge of the CBD was only a possibility. “It almost didn’t happen,which would have been a really disappointing outcome,” Staples says. “We actually had[the line] going from North Sydney straight through to Martin Place and Town Hall. It was one of those moments where I became quite convinced that this was something we really needed to add to the project.”

The governmentcommitted to it in mid-2015 when it allowed the development of larger buildings on the 5.2-hectare Barangaroo Central site,the last of the precinct’s three sections.

The line was initially to be at surface level along an existing rail corridor from Chatswood to St Leonards,but plans were later altered so that it would run through tunnels along that section.

Contrarians

Five years after Metro Northwest opened $1 billion under budget in May 2019,the cost of the second stage of the metro network is nearing $22 billion – almost double its original price tag of about $12 billion. “I cannot believe the price of that project now,” Les Wielinga says. “You’ve got to get the contract strategy right in the way it’s built and the timing of it.”

Sporting flashy finishes,the stations open the project up to suggestions of gold plating,especially when Sydney’s existing double-deck rail network will carry the bulk of rail commuters after the new metro line opens.

Dick Day,the man whomasterminded the train timetable for the Sydney Olympics,agrees the line will deliver much-needed rail capacity through the city centre,and relieve pressure on the existing train system. But he says the “greatest deficiencies” in the project’s design is south of Sydenham,condemning the metro line to run at half its maximum capacity of about 30,000 passengers an hour in each direction.

Day says conversion of two of the existing rail tracks between Sydenham and Hurstville,in addition to Bankstown,would have fed more passengers into the metro system,and relieved pressure on the Illawarra line from southern suburbs and the south coast.

That idea was quickly abandoned last decade because the driverless metro trains were incompatible with the existing rail system,and could not share the route with freight trains. “The new metro stations are built on a lavish scale and will manage substantial amounts of people. There’s no doubt about that,” Day says. “The problem is that it can’t in its current configuration ever be used really to its full capacity,particularly for the Bankstown end because there just aren’t that many people along that corridor.”

Day is one of four former NSW rail executives towarn in 2017 that the Metro City and Southwest line would lead to a “degradation of the robustness and reliability” of the existing heavy rail network. They feared a “takeover” of the existing rail line from Sydenham to Bankstown for metro trains would remove “the relief valve for the network”.

Staples is blunt in describing that argument as “incomprehensible”,pointing out that the most congested part of the rail network is where the East Hills,Inner West and Bankstown lines converge into one as they converge on Central Station. “It’s a simple maths equation. You take one of those out,you make the network more resilient,” he says. “What it’s doing is it’s providing two systems. If we have a really bad incident on the Sydney Trains network in the city,most trains to most lines stop. If the Metro stops,Sydney Trains still runs,and if Sydney Trains stops,Metro still runs.”

Problem child

Under early planning,Staples and his team weighed up converting either the Inner West,East Hills or the Bankstown lines for metro trains because they all fed into the City Circle line under the CBD. They decided in 2012 that the Bankstown line was the best choice because it offered more benefits to commuters and was not adjacent to other lines.

In hindsight,the conversion of the Bankstown line has proved much more difficult than envisaged,partly due to the heritage-listed stations and curved platforms. The pandemic and anindustrial dispute added to the challenges.

Even after scaling back the scale of the work,the Perrottet government came close to ditching the conversion in late 2022,months before the election. The incoming Labor administration weighed up its options before deciding to proceed,injecting anextra $1.1 billion to finish the job.

“It’s very different when you’re building something new with all the modern technology,you can build to such precision,to millimetre perfect,” Sydney Metro’s Regan says. “That[Bankstown] rail line is 130 years old,and the embankments and the structure of it reflects when it was built.”

City shaping?

Four years after the pandemic struck,working from home remains commonplace,leaving Sydney’s rail patronage at about 80 per cent of pre-COVID levels.

Regan says the new metro stations and developments will be city-shaping in their own right,while changing commuters’ behaviour. “Once the city section is opened from Chatswood to the city,it won’t be quicker to drive or take the bus. It will actually be much quicker to get on the metro on the northwest and stay on the metro,” he says. “The objective of this isn’t to have a station on every corner. This is about high volume,high capacity,high frequency.”

He believes the response from commuters will be similar to London’s newElizabeth line,which has exceeded patronage forecasts since its 2022 opening. “It’s fast,and it’s reliable,and … that’s attracted people to switch modes,” he says.

More than 264,000 passenger trips are forecast between Sydney’s northwest and Sydenham each weekday when the metro extension opens. At present,patronage on Metro Northwest is just shy of 100,000 trips on weekdays.

“It’s definitely the biggest insertion of transport capacity since the Harbour Bridge,” Regan says. “The metro under the harbour actually has more capacity than the Harbour Bridge and Harbour Tunnel combined per hour ... in terms of the number of people that you can put through. It will change the way people around.”

It was hugely ambitious for Berejiklian to commit to building a driverless rail line under the harbour more than a decade ago. “To build Northwest with a desire to come to the city was a very long-held vision. But the decision to go with the next-generation systems,with automated systems,was a big call,” Regan says.

Sydneysiders will now decide for themselves whether it was the right call.

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