On this backing, the Australasian Tunnelling Society (ATS) continues to promote tunnelling, having just completed the 4th Tunnel Design and Construction short course. The course was held in Sydney at the University Technology Sydney (UTS) over three days, with over 170 students attending. The ATS has also continued to see success with the David Sugden Writing Contest where the winning young engineer has travelled to international tunnelling conferences around the world.
In recent years we started the New Zealand chapter and changed our name to the Australasian Tunnelling Society. Our special interest group, the Australian Shotcrete Society, will be holding an international conference in Queenstown, New Zealand in March 2010.
New South Wales
Sydney continues to be busy with the Sydney Desalination Plant nearing completion and Sydney Metro now underway. Metro West is also hovering in the wings with talk of at least two major freeway tunnels in the offing with expansion of the M5 Corridor including duplication of the M5 East Tunnel. The 7 km CBD Metro is the first step towards a metro rail network for Sydney. It will run underground between Central and Rozelle via Town Hall Square, Martin Place, Barangaroo/Wynyard and Pyrmont. A station will also be safeguarded for future development at White Bay. The platform depth at the stations will range from approximately 20 to 35 metres below street level. The tunnel depths will be further determined as the design progresses. The CBD Metro will be excavated primarily by two “÷earth pressure balance’ tunnel boring machines (TBMs). The TBMs will be launched from White Bay and will head towards Central, passing beneath the harbour floor. Roadheaders will be used to excavate the station caverns and a small section of the tunnels (between White Bay and Rozelle).
The focus of Australian tunnelling has been in Brisbane in recent years with completion of the Boggo Road tunnel, the Clem Jones Tunnel reaching the final stages, the 5.25 km Airport Link underway and calls of Expressions of Interest for tenderers for the 4.5 km winning tender on the Northern Link from Mt Coot-tha Roundabout to the Inner City Bypass expected to be awarded early announced in October 2009 (see page 11).
Following a two-year, $A19 million investigation, the Western Brisbane Transport Network Strategy has proposed the Inner Orbital Tunnel and the Stafford Road Tunnel. The Inner Orbital Tunnel is an 8 km road tunnel between Toowong and Everton Park. The Stafford Road Tunnel is an urban motorway tunnel under Stafford Road to connect the proposed North West Transport Corridor and Inner Orbital with the Airport Link.
The next major project will be the Cross River Rail, targeted to commence in 2012 and completed by 2016. This is a major tunnelling project involving new CityRail “÷heavy track’ system rail lines through the inner city, along with an under river crossing and new underground stations, meaning more frequent trains and better services for all of south east Queensland’s rail users. Initial estimates value the project at approximately $A8 billion.
Premier Anna Bligh has also announced a focus on an underground metro for Brisbane; Premier Bligh’s vision for an underground light rail project linking Toowong, West End, the CBD, Newstead, Bowen Hills, Bulimba and Bowen Hills by 2030 promises more tunnelling into the future.
Following completion of the Gold Coast Desalination Plant and Tugun Bypass, in recent years we have also seen the completion of the 300 m cut and cover tunnel for the Robina to Varsity Lakes Rail Extensions.
Tunnelling continues on the Northern Sewerage Project and the Melbourne Main Sewer upgrade. Recent discussions have been on improving train and road travel across Melbourne, with a number of tunnel options put forward.
The Northern Sewerage Project includes an 8 km long deep-tunnelled sewer in stage 1 connecting the existing sewerage system near the Merri Creek at Coburg and the Moonee Ponds Creek in Pascoe Vale, and a 4.6 km long, deep-tunnelled sewer running from Carr Street, Coburg North, to
L.E. Cotchin Reserve in Reservoir, and diverting sewage flows from the existing sewerage system in Fawkner in stage 2. Both sections are being constructed by John Holland and are timed for completion by mid-2012.
The Bogong Power Development has been completed in the Victorian Alps adding the final power station to the Kiewa Hydro Electric Scheme as it was originally envisaged in the 1950s. It includes a 6.5 km underground tunnel from the existing McKay Creek Power Station to the new station at Bogong (see page 7).
The Government has been promoting its plans, including two new road tunnels, an extra train line, a new city subway and extra public transport services. Scoping works have begun on a proposed $A4.5 billion rail tunnel under Melbourne, which includes new stations at Parkville and St Kilda Road, as part of the Victorian Government’s Transport Plan. The Victorian Government also wants to build a road tunnel under the Maribyrnong River to ease congestion on the West Gate Bridge.
Significant projects continue to develop in Western Australia following completion of the successful New Metro City Rail Project in Perth a few years ago.
Tunnelling on the Alkimos Wastewater Project has been successfully completed by the project Alliance (Multiplex/Macmahon/Zublin JV). The second desalination project in Western Australia, south of Perth at Binningup involves an onshore pipejack beneath the coastal sand dunes and sensitive environments. The project has commenced, but tunnelling is yet to start.
The Perth Airport Rail Link Study is underway; with a primary outcome to allow the State Government to set aside land for a future project that includes tunnels under the runway of, and underground stations at, the Perth Airport. The study was awarded by the Public Transport Authority (PTA) to AECOM in February, 2009 and should report soon.
The PTA Hub Project involves lowering the Fremantle rail lines above the existing Joondalup line-bored tunnels and also the lowering of the Wellington Street Bus Station. This will enable redevelopment of the Perth Rail Yard land for public open space, residential and commercial towers and other civic purposes. The Hub Project is in Master Planning Stage, with Commonwealth Government funding allocated to the project and decisions awaited on State Government funding and programming.
After a few quiet years in tunnelling South Australia is set to take off again with the Adelaide Desalination Project starting up. The project includes three shafts, one underground intake cavern, and two tunnels to ocean intake/outfall.
A six km road tunnel in Adelaide is also among changes the Royal Automobile Association (RAA) is urging for the road traffic network. It favours a continuous 22 km of driving on South Road and the six km tunnel to be built between Anzac Highway and Croydon.
The development of underground infrastructure is looking increasingly positive. Recent projects completed include Watercare Services’ Hobson Bay Sewer Tunnel and Johnston’s Hill twin road tunnels. In Auckland, the Victoria Park cut-and-cover tunnels have begun, while planning and design proceeds on the Waterview Link tunnels and on the City Centre Loop project.
Work has started on the 440 m Victoria Park Tunnel in Auckland aimed at eliminating a major bottleneck between the central city and Auckland Harbour Bridge. Contractors aiming to finish work on the tunnel before the Rugby World Cup in 2011 (see page 22).
Excavation of the 3 km long tunnel at Hobson Bay was successfully completed 17 days ahead of program. The average production rate achieved was 114 m per week with a best day rate of 37 m in 24 hours. Commissioning will be complete before Christmas 2009 (see page 14).
The Rosedale Outfall Project is the current major underground project in Auckland region. The tunnel drive is through sandstones and mudstones of 2-6 MPa UCS by a Lovat EPB TBM. With two out of three kilometres done and an average progress rate of 130 m per week, the excavation phase of the project should be completed by Christmas.
Other projects include the South West Interceptor in Auckland, the Western Interceptor in Christchurch, and the Meridian Energy “÷Rockwater Power Project’ in the south.