^Actually, the fourth track already exists north of the Wallace Ave footbridge, in bits and pieces. It’s just a matter of connecting what’s there with new fill-in bits, once Mount Dennis and Weston stations are finished.
The plans for the section from Wallace Ave eastwards can be found in the Railpath consultations. The railpath is shifted/squeezed, the Bloor station pedestrian tunnels are extended eastwards with new portals, the unused bridge at Bloor is shifted east a touch, and track is laid down to King Street... and again, there is track already laid in bits and pieces. The junction with the Barrie line at Parkdale is removed, and again bits of track are connected with new bits laid here and there, giving the Barrie line its own double track line once the Davenport Overpass is finished.
East of about Brock Ave, the Milton line shifts to a new track, and the existing Milton line becomes the fourth track of the Georgetown line.
Simple, eh?
- Paul.