The Toronto council in Canada has approved a $640m plan to revamp its Union Station.

The plan is aimed at transforming the heritage building into a destination with an underground floor of retail shopping and restaurants.

The project is being half funded by city government and an undisclosed private investor and the remainder by federal and provincial grants.

The scope of work envisages digging out a new 120,000ft² area for a retail space and a tunnel at the northwest corner connecting to the city’s PATH system.

The plan includes building two new GO Transit concourses and renovating the Great Hall.

In addition, the entire station building will be made nearly 30% more energy efficient. A new atrium roof over the tracks will be braced by a sustainable green roof and parts of VIA Rail will be improved.

The plan will be finalised in September 2009 and work is expected to begin in early 2010 and be complete by 2015 .