Land will have to be acquired to make way for the new Melbourne Metro Rail Project.
Planners say it's still too soon to know how many homes and businesses will have to go to accommodate the multi-billion dollar project.
Those affected will be notified in the coming months as numbers are finalised, Melbourne Metro Rail Authority chief executive Evan Tattersall told a parliamentary hearing.
Properties will likely be both homes and businesses in the CBD and potentially in the suburbs.
"We are doing a lot of things to minimise any land take but there will be land take," he said.
"But for a project of this scale, it's not massive."
There has been broad consultation with those in affected areas but specific consultation with property owners who will be affected by the acquisition is still to come.
Consultation has already begun with those who will be affected during construction including Swanston Street traders and Bicycle Network Victoria.
Construction is due to begin in 2018 and take eight years to complete.