The Sydney Metro City & Southwest (SMCSW) project will extend the metro rail between Chatswood and Marrickville and will include a new tunnel beneath Sydney Harbour.

Arcadis and BG&E in a joint venture (ABJV) were engaged to do the tunnel station excavations, surface civil works and selected permanent and temporary works structures. In addition to the original scope of work, BG&E’s team of engineers have provided construction engineering assistance and temporary work design.

The SMCSW is a 15.5 kilometre project, spanning from Chatswood to the Marrickville area, including a crossing beneath Sydney Harbour.

The project includes

• Constructing running tunnels with waterproofing using tunnel boring machines (TBMs) for dry tunnels, mined cross passages, a cavern for a rail crossover at Barangaroo, tunnelling below Central Station, and creating mined station caverns with adits for new stations at Victoria Cross, Martin Place, and Pitt Street, including a connection to the existing Martin Place Station on the Sydney Trains Eastern Suburbs Line.
• Demolition, excavation, and concrete structures for dives in Chatswood and Marrickville, as well as for new stations in Crows Nest, Victoria Cross, Barangaroo, Martin Place, Pitt Street, and Waterloo.
• Installing a permanent concrete lining in all tunnels, caverns, adits, cross passages, and underground openings to accommodate future track bed and rail and station services. It also includes constructing the primary concrete structure at the new Barangaroo station and ensuring safe personnel access to underground spaces with temporary support services, including maintaining site facilities for handover to Follow-on Contractors upon completion.
• Removal of all temporary work and site facilities not otherwise required for handover to Follow-on Contractors.

The ABJV are responsible for following scope of works for the TSE design

• Design of temporary and permanent civil works (roadworks, drainage, temporary and permanent storm water diversion, flood modelling, utility coordination, road safety audit, traffic modelling, traffic staging, temporary works etc.).
• Design of temporary and permanent structures for all open box, shaft and dive sites (bored and CFA piling, shoring, steel platforms, deep excavation over 40m, drained and undrained structures, etc.).
• Building effects assessment.
• Project wide durability assessment.
• Earthing and electrolysis assessment.
• Project wide flooding assessment.
• Project wide CAD and BIM management.