The CRL will comprise a 3.5km tunnel running from Britomart under Albert, Vincent and Pitt Streets, then beneath Karangahape Road and the Central Motorway Junction before rising to join the western line at a triangular junction near Eden Terrace. Stations are planned at Aotea, Karangahape Road, and Newton on the new line, with a new Inner West Interchange station on the western line south of Dominion Road.
The section between Britomart and Aotea will use cut-and-cover construction, while the remainder of the new line will run in twin-bore tunnels at depths of up to 45m, which will be excavated using TBMs.
The total cost of the CRL is expected to be around $NZ 2.23bn ($US 1.79bn), including $NZ 259m for the acquisition of additional emus and $NZ 108m for associated improvements to existing infrastructure.
Auckland Transport will start consultation with local property owners this year and start formal planning processes to designate the land required. Planning will take three years, and construction would take around five years to complete. Auckland Transport hopes to commission the link in 2020-21.
The line will double the number of people able to reach a city station within 30 minutes. The journey time between New Lynn and Aotea will be reduced from 51 to 23 minutes, while the Manukau Centre – Karangahape Road trip will fall from 1h 1min to 42 minutes. "The CRL won't just provide a convenient rail link beneath the city centre, it will unleash the potential of the entire suburban rail network, increasing frequency, reliability, and the speed of trains across Auckland," says mayor Mr Len Brown.