Commuters heading through Union Station will get a new experience on Monday when the food hall in the York Concourse officially opens.

It marks a major milestone for the redevelopment of the iconic train station, a project that is years behind schedule and considerably over budget. The projected cost has ballooned from $640 million to $823 million over the course of construction.

"We've worked really hard to have a retail experience that is unique and really represents the best of Toronto," said Vanessa McDonald, who manages partnerships for the station.

The lower level adds 25,000 square feet of new space to the storied building. Bangkok Buri, Loaded Pierogi, McDonalds, Paramount Fine Foods, Pizza Pizza, Roywoods, Scaccia, Shanghai 360, Sushi Shop and Tim Hortons are among the restaurants that will be open in the food hall.

"The trends have been more to a fast casual environment," said Monte Wan, co-creator of Bangkok Buri.

"I'm excited about actually finally getting to that point. And the other [eateries] are also upping their game," Wan added.

A variety of options will be available when the food hall opens with extended hours from 7 a.m. to 10 p.m. (Paul Borkwood/CBC)

Improving the experiences of the more than 300,000 people who travel through Union Station each day was a core goal of the revitalization project, according to the city.

"It's fantastic to have more services," said Phil Verster, CEO of Metrolinx. The regional transit agency has trains and buses running to and from Union every day.

McDonald said the vision for the revamped station is guided by the question: Where is Toronto going? Ultimately, planners hoped to create a sense of community.

"Next is a fresh market space and that's very similar to St. Lawrence Market — where you've got independent curated retailers," she added.

Due to construction delays, however, there's no timeline on when that space will open.

Construction woes

The massive project was initially scheduled to be completed in 2015, in time for the Pan Am games. It has seen years of delays and a number of significant budget increases.

With the completion date now revised to 2019, the city pointed to contractor Bondfield Construction as the source of the backlog.

The project is jointly managed by the City of Toronto, which is handling the restoration work, Metrolinx, which is overseeing the transportation infrastructure improvements, and Union Station, which manages the retail and services. (Mehrdad Nazarahari/CBC)

In a statement, a spokesperson said the city is "very disappointed and frustrated" with the rate of progress.

"The Union Station Revitalization Project, seemingly along with a number of other Bondfield Construction projects across the province, has experienced significant delays in recent months."

Projects in Thunder Bay and Cambridge are among those similar facing significant delays.

Bondfield Construction did not respond to a request for an interview with CBC Toronto.

City reluctant to commit to completion date

Delays in the project have led city staff to start discussions with the contractor's surety company, Zurich Insurance.

Staff said that they're in discussions with both companies "regarding possible paths forward to complete the project in 2019," adding that city hall is "actively managing this project, and will assess all future options, to ensure its completion."

When pressed for details on the new timeline, city staff would not comment, saying only that 2019 is the target year for completion. An updated schedule will be provided "as soon as it is available."

Despite the delays, city officials stress significant progress has been made on the project overall. The York Concourse is now completed, in addition to the VIA Rail lounge and bicycle parking stations.

Work is now shifting to the restoration of the Great Hall, the concourse where VIA passengers arrive and depart, the new Bay Concourse and installing glass coverings over outdoor areas of the station.