drum118
Superstar
I really think that you could fit 4 tracks on the line with little or no expropriation. With sidings, it's already 3 tracks wide in many places and there's still room to spare.
There are some spots that can hold a 4th track, but not in the build up areas. From Dundas going east to Dixie will only support 3.
From Confederation to west of Erindale Station Rd, will only support 3.
The bend at Mississauga will require property to be bought on the west side. I have no idea how a grade separation can be built there without doing a major impact on the area.
Getting under the Erin Mills overpass has major issues for 3, let alone 4.
Going through Streetsville has some issues with the high school on the west side of the tracks as well crossings.
Since CP see less than 50 trains a day and mostly at night and 3 tracks is good enough for now to support 30 minute service 7 days a week.
There are sections that have 3 tracks in place with the 403 to Confederation section as one of them.