C1 Completion - Another Milestone Ticked Off
Hard on the heels of our successful TBM breakthrough at Karangahape was another big celebration for City Rail Link (CRL) – this month marked the end of one of the most complex and astonishing engineering challenges undertaken in New Zealand.
Over five years of exceptional and innovative work that pushed construction techniques to new limits ended with the completion of our C1 contract at Britomart Station.
C1 preserved Auckland’s past while building a world class rail system for a growing and modern city. Critical to CRL’s success was turning the dead-end Britomart Station into a two-way, through station with twin rail tunnels built in the basement of the city’s imposing and historic Chief Post Office (CPO).
Work began in 2016 when the CPO, the main entrance to the Britomart Station, was closed. CRL Ltd and its contractors, Downer NZ and Soletanche Bachy JV, built the tunnels in the basement of the 109-year-old heritage-listed building, across the lower end of Queen Street and below the Commercial Bay office and retail development to connect with CRL tunnels in Albert Street.
“A great ‘can do’ attitude produced an outstanding outcome for the city,” says CRL Chief Executive, Dr Sean Sweeney.
C1 works included:
Fourteen thousand tonnes of a building (with a top heritage rating) were safely transferred on to temporary foundations
Building a temporary Britomart Station to use while we dismantled the ground floor of the CPO
Machinery was modified specifically for use in confined conditions under the CPO
Special grade steel manufactured in New Zealand for the first-time was used in the contract
Workers had to contend with muddy reclaimed land with the old building perched on temporary foundations just a few centimetres above them
Britomart Station remained fully operational with a connecting door separating busy platforms from a construction site
Delivery was challenged by multiple Covid-19 Alert Level 4 lockdowns in Auckland
Years of planning, design and partnerships involving CRL Ltd and its contractors with Heritage NZ, Auckland Council, Auckland Transport, the Commercial Bay developers, other neighbours, and Tāmaki Makaurau iwi were the foundations for the positive outcome.
Around 10,000 Aucklanders were given a ‘sneak peek’ behind the project’s hoardings when they walked a section of Britomart tunnels in November 2019, during a one-off “Walk the Tunnels” event.
The project handed back to Auckland a fully restored CPO last April and the building has resumed its role as the “front door” to Britomart Station once again.
Traffic-congested Lower Queen Street in front of the CPO has been replaced by a striking people-friendly square known as Te Komititanga, meaning to mix or to merge. The layout of Te Komititanga’s basalt pavers was designed by Mana Whenua artists and weavers.