The City Rail Link (CRL) is a 3.45 km twin-tunnel (twin bored and mined) underground rail link 42m below Auckland’s Central Business District that was constructed to support the exponential growth of New Zealand’s largest city. The CRL enhances the Auckland rail network, allowing trains to run both ways through Britomart, the busiest station in New Zealand. This efficient and reliable transport investment will support economic development and significantly ease congestion in the central city. The rail network can double peak flows to 54,000 people an hour.

CRL will connect downtown at Waitematā Station (Britomart) with a re-developed Maungawhau on the Western Line. Construction includes three new stations and links into the North Auckland Line. This includes two new underground stations (caverns), one 300 m long, 20 m deep top-down cut and cover station at Aotea, and the other comprising two 32 m deep top-down shafts and mined excavation platform tunnels at Karanga-a-Hape. The project works include deep portals, tie-ins, and mechanical, electrical, fire, hydraulic, and rail systems.

Of note, the Mount Eden Station will be the largest developed site in the CRL project and will have a distinctive impact on future development in the Mount Eden area. This package included realignments, upgrades and extensions to the existing public realm and streetscape network around the new station.

CRL construction began in late 2016, with completion and handover due in late 2024.


  • An alternative underground route of the rail alignment via Albert Street ridge (a value engineering approach adopted by AT)
  • ECI phase technical advice
  • Assessment of potential settlement effects on surrounding structures along the entire CRL alignment
  • Geotechnical peer review of the main temporary and permanent civil retention and break through works
  • Preliminary design of alternative solutions, monitoring requirements and input into the construction methodology for the enabling works during the tender design phase
  • Geotechnical advice and support during the ECI phase, including alternative retention designs and value engineering improvements
  • Additional geotechnical site investigations
  • Preparation of the Groundwater and Settlement Monitoring Contingency Plan
  • Planning services involving coordination and preparation of the construction management plans required as part of the resource consent
  • Space proofing and layout planning of the running tunnels and platforms for all utilities and rail systems
  • Full detail design of the underground civil works
  • Geotechnical structures for the NASL connections
  • Leading and coordinating the design development and detailed design of the package as well as the delivery of various interim and enabling works packages
  • Running Safety In Design, design coordination and consultation workshops
  • Designer responses to Road Safety Audits
  • Design reviews and reports
  • General coordination with interfacing packages
  • Signals design, signage, and markings design
  • Vehicle tracking assessments and street design
  • Also advised on planning and consenting aspects


  • Auckland Transport
  • City Rail Link


  • 2012 – current

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