An Alliance of Laing O’Rourke, Fulton Hogan and Jacobs will deliver the multi-million dollar works, with work to begin in the coming months.
The project includes the construction of a rail bridge over Lower Plenty Road, removing the crossing and helping to reduce congestion and improve access to local shops and parkland.
The bridge will also help prevent disruptions to services caused by flooding.
The second track will be built to the east of the existing tracks, but will not require any property acquisition. The duplication will include a new tunnel under Darebin Street next to the existing brick tunnel.
The works are part of a $395 million package of works that also includes the removal of the Grange Road level crossing in Alphington.