Planning approval process of the project was done in stages due to the size of the project. In March 2021, planning approvals were granted to the project concept between Westmead and the CBD, and station excavation and tunnelling between Westmead and The Bays. Future planning stages will seek approval for major civil construction works including station excavation and tunnelling between The Bays and the CBD, tunnel fit-out, station building, and operation of the line between Westmead and the CBD.
