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Sydney Metro Harbour tunnel
Tunnelling
Sydney Metro West
Three major tunnelling contracts have been awarded for tunnelling between Westmead and Hunter Street in the Sydney CBD, and began tunnelling in 2023. Follow the journey of our tunnel boring machines (TBMs) with our TBM tracker.
About our tunnels
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Sydney tunnel depths
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Marrickville cutterhead lift
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Barangaroo TBM cutterhead
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TBM Mum Shirl being lifted
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Victoria Cross breakthrough
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Chatswood dive tunnels
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TBM Kathleen barge move
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Our tunnel boring machines
Six TBMs will be used to deliver the tunnels between Westmead and the Sydney CBD for Sydney Metro West.
Four TBMs will be used to deliver the tunnels for the Sydney Metro -Western Sydney Airport project from Orchard Hills to St Marys and between Airport Business Park and Aerotropolis Station.
Five TBMs were used to deliver the tunnels between Chatswood and Sydenham for Sydney Metro City & Southwest. This included a specialised TBM for the section under Sydney Harbour because of the ground and rock conditions found at the bottom of the harbour.
Four mega tunnel boring machines built the twin tunnels on Metro North West Line. This was the first time in Australian history four TBMs were used on the one transport infrastructure project.
Naming the TBMs
On major tunnelling projects around the world, underground workers look to Saint Barbara for protection. Because of this, machines that work underground are traditionally given female names.
Sydney Metro West TBMs
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TBM1 was named after Daphne Hilton who is not only an icon in Paralympic sport but is one of the most successful Australian athletes of all time.
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TBM2 was named after Beatrice Bush who sold newspapers seven days a week from the traffic island at the intersection of Victoria Road and The Crescent in White Bay for 25 years until 1996.
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TBM3 was named after Australia's Golden Girl, Olympic champion and world-record holder Betty Cuthbert who grew up in the Parramatta area.
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TBM4 Dorothy was named after Buckland-Fuller AM, MBE an Australian sociologist, human rights activist and migrant community advocate who founded the Australian Migrant Women's Association where she had been integral in aiding migrant women, alleviating their sense of isolation.
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TBM5 was named after Jessie Street an activist, feminist and lifelong campaigner for women’s rights, the peace movement, and the elimination of discrimination against Aboriginal people.
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Sydney Metro - Western Sydney Airport TBMs
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TBM1 was named after Eileen Cammack OBE who was the first female mayor of Penrith and established the first pathology laboratory at Nepean District Hospital in 1948.
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TBM2 was named after Peggy Kelman OBE who was an aviation pioneer, adventurer, and flying companion of Nancy-Bird Walton, the namesake of the new international airport. Peggy Kelman (left) with Nancy-Bird Walton (right)
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TBM3 was named after Catherine White who has worked tirelessly to promote social justice and gender equality, and advocate against violence towards women in the Blacktown area.
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TBM4 was named after Dr Marlene Kanga AO for her significant contribution as a global leader in engineering and role model to women in STEM. Marlene was chosen by students from Claremont Meadows Public School.
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Sydney Metro City & Southwest TBMs
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TBM1 Nancy was named in honour of Australian aviation pioneer Nancy Bird Walton OBE, the first female pilot in the Commonwealth to carry passengers and the founder of the Australian Women Pilots’ Association.
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TBM2 Mum Shirl was named in honour of Colleen Shirley Perry, a Wiradjuri woman who dedicated her life to her community, raising 60 foster children and was involved in establishing legal, medical, housing and cultural services for the Aboriginal community.
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TBM3 Wendy was named after Wendy Schreiber, a volunteer at Bear Cottage – the only children’s hospice in NSW and long standing charity partner for the Sydney Metro tunnelling contractor John Holland CPB Ghella.
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TBM4 Mabel was named after Mabel Newill, a matron at Royal Prince Alfred Hospital - she helped stop the spread of typhoid in Sydney, in the early 1900s.
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TBM5 Kathleen was named after Kathleen Butler, who worked on the Sydney Harbour Bridge – technical advisor to legendary engineer John Bradfield – a century ago.
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Sydney Metro Northwest TBMs
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TBM1 Elizabeth was named after colonial pioneer Elizabeth Rouse, by Alexandra Marshall from Rouse Hill Anglican College after winning a school competition.
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TBM2 Florence was named after Australia’s first female engineer and architect, Florence Mary Taylor.
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TBM3 Isabelle was named after four-year old Isabelle Andersen by tunnel builders CPB John Holland Dragados. Isabelle represented the families of the tunnelling workers.
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TBM4 Maria was named after 19th century Aboriginal rights advocate Maria Lock.
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Tunnel safety
Safety of customers is the number one priority. Tunnel safety measures include cross passages linking the twin tunnels and constant camera coverage.