Every weekday people pass through Toronto's Union Station a quarter of a million times. That makes it Canada's busiest transport hub, and with all of the improvements coming to GO Transit and the TTC over the coming years that number is only going to grow. To handle the forecasted crowds and to better serve them the whole station is seeing many improvements, mostly accommodated in new space created in areas that were, until recently, rental car parking or storage or which were disused. A lot of the new space is also going in what simply used to be the ground, and the dig-down to create the new space is what presents the greatest engineering challenge. Until now UrbanToronto readers have been able to pore over the plans in our dataBase entry and imagine how it all might look. Now, with a media tour providing access to the construction site, your imagination can be given a boost through photos showing significant progress since an introductory tour in the summer of 2011.

Union Station Revitalization Project Replacement, TorontoThe tour group heads into the construction zone of Union Station, image by Jack Landau

Union Station Revitalization Project Replacement, TorontoWork continues on extending supporting columns of Union Station, image by Jack Landau

Trains still must come and go constantly above, of course, so the work below must not disrupt the functioning of the station. Columns, each built directly below the tracks, must be lengthened as the earth is dug out around them. Temporary steel braces provide the required strength until the newly poured concrete cures around rebar reinforcement. The dig down is going four metres below the existing grade and about 45 truckloads are needed to remove the approximately 600 to 900 tonnes of material excavated daily.

Union Station Revitalization Project Replacement, TorontoSignificant amounts of earth are being removed under Union Station, image by Jack Landau

About 150 of the 447 columns are now lengthened or replaced. The procedure is rarely practised around the world and contractor Carillion Construction has now developed an unmatched expertise through the scale of the work required here. Where the excavation is complete and the columns lengthened, new floor slabs are being poured. Concrete is delivered through piping from the York Street loading docks, and about 800 cubic metres has been formed so far.

Union Station Revitalization Project Replacement, TorontoThe scale of work under Union Station is vast, image by Jack Landau

Union Station Revitalization Project Replacement, TorontoReadying columns for a new floor under Union Station, image by Jack Landau

At the south end of the dig-down, new floor slabs now form an intermediate level which will serve commuters going to and from GO Trains above. The new lower level will provide spaces for shops and a food court: waiting for a train will get a lot more diverting.

Union Station Revitalization Project Replacement, TorontoA recently poured second floor reveals new mall area under Union Station, image by Jack Landau

Along for the tour with the media were, left to right below, John Carmichael, MP for Don Valley West, Denzil Minnan-Wong, City Councillor for Don Valley East, Mayor Rob Ford, and City Councillor for Etobicoke Centre and Deputy Mayor Doug Holyday.

Union Station Revitalization Project Replacement, TorontoPhoto op: John Carmichael, Denzil Minnan-Wong, Rob Ford, Doug Holyday, image by Jack Landau

The work is at varying stages of progress in different areas, but a great push is on to complete a new western concourse for GO Train commuters to be called the York Street Concourse. It should open in late 2013 or early 2014. When it opens the existing Bay Street Concourse will close so that it can be rebuilt. Once the Bay Street Concourse re-opens in 2016 the station will be able to accommodate many more people traveling through it. The mall area meant to make the experience more pleasant and more convenient should open in 2015.

Union Station Revitalization Project Replacement, TorontoExcavations continue under Union Station, image by Jack Landau

Union Station Revitalization Project Replacement, TorontoScale: under Union Station, image by Jack Landau

Union Station Revitalization Project Replacement, TorontoShoring and square columns under the VIA Concourse at Union Station, image by Jack Landau

Union Station Revitalization Project Replacement, TorontoMassive columns under a portion of the VIA Concourse at Union Station, image by Jack Landau

Union Station Revitalization Project Replacement, TorontoForms hold a newly extended square column in place below the VIA Concourse at Union Station, image by Jack Landau

Union Station Revitalization Project Replacement, TorontoCompleted columns and new floor under a portion of Union Station, image by Jack Landau

Union Station Revitalization Project Replacement, TorontoThe dig-down continues for services in an area with completed columns at Union Station, image by Jack Landau

If you have wandered through the PATH connection between Union Station and the Air Canada Centre, you'll be familiar with the pathway pictured below and its gentle rise and fall.

Union Station Revitalization Project Replacement, TorontoTemporary walkway to the Air Canada Centre at Union Station, image by Jack Landau

What you wouldn't be familiar with is what is find behind the walls and under the floor here. Below, you can make out the sloping gradient of the passage. All of that passage is temporary; it will come down when another permanent connection opens.

Union Station Revitalization Project Replacement, TorontoBelow the temporary walkway to the Air Canada Centre at Union Station, image by Jack Landau

Union Station Revitalization Project Replacement, TorontoColumn forms await another concrete pour under Union Station, image by Jack Landau

Up top again, and we got a peek at the first restoration project to be completed at the station, the Panorama Lounge for VIA Rail's first class passengers. UrbanToronto visited the lounge upon its opening earlier in the year.

Union Station Revitalization Project Replacement, TorontoCompleted Panorama lounge for VIA first class passengers at Union Station, image by Jack Landau

Finally, outside and in front of Union Station there are giant holes in the sidewalk and Front Street where the TTC and Waterfront Toronto are building a new south platform for the overcrowded subway station. Totalling up all of the projects underway in and around Union Station to improve transportation at the moment: the Station, the Train Shed Glass Atrium, new offices for GO Transit and Metrolix, the Subway Station Expansion, and a new Northwest PATH System Extension which will soon be underway, and over a billion dollars — coming from the three levels of government and various agencies — is being spent.

Union Station Revitalization Project Replacement, TorontoConstruction to expand Union Subway Station disrupts Front Street, image by Jack Landau

Union Station Revitalization Project Replacement, TorontoConstruction to expand Union Subway Station disrupts Front Street, image by Jack Landau

Anyone who uses Union Station on a regular basis knows the improvements have long been needed and cannot be finished soon enough. With the progress to date there is finally something concrete to hang our hopes on, and we will soon be counting the months instead of the years until major openings of the work are scheduled.

Want to know more about what's coming? Plans and renderings can be found in UrbanToronto's dataBase entry for the project, linked below. Want to get in on the discussion? Leave a comment here, or choose the associated Forum thread linked below as well.