It looks like there is a point where the proposed Oshawa-Bowmanville GO train track is going to have to pass UP, OVER and DOWN on the other side of the CP freight track on the north side of Hwy 401 east of Thornton Rd.
It seems this is due to the elevation of where Metrolinx will be building a new GO bridge parallel (and on the west side of) the current GM Spur bridge.
Following the Feb 2, 2021 virtual Town Hall I emailed Metrolinx asking for a sketch to understand better the 2 track 'diamonds' they mentioned where the tracks were going to 'interlace' at two points on the north side of the Hwy 401 near Thornton Rd.
Here is what Metrolinx wrote back: "we are still in the process of working through the design, we are unable to share a sketch at this time. However, I will attempt to give a better description."
"From Oshawa station heading east the track will rise and turns north to run parallel with the GM spur. The bridge over the 401 will be enhanced to carry a second deck or span for a second track specifically for the passenger trains. Immediately to the north of the 401 the CP track drops slightly and the new passenger track will rise over the top separating operations."
"The track will then drop and head east towards Bowmanville parallel to the CP track."
(I couldn't find any pictures of an elevated passenger train track from a bridge over a highway going over a freight train track, but thought I'd add a picture below for a visual of sorts.) Imo, it is difficult to imagine the aesthetic of the GO track rising over the 'top separating operations', which I assume means overtop of the CP freight track, because of what Metrolinx described.
It seems this is due to the elevation of where Metrolinx will be building a new GO bridge parallel (and on the west side of) the current GM Spur bridge.
Following the Feb 2, 2021 virtual Town Hall I emailed Metrolinx asking for a sketch to understand better the 2 track 'diamonds' they mentioned where the tracks were going to 'interlace' at two points on the north side of the Hwy 401 near Thornton Rd.
Here is what Metrolinx wrote back: "we are still in the process of working through the design, we are unable to share a sketch at this time. However, I will attempt to give a better description."
"From Oshawa station heading east the track will rise and turns north to run parallel with the GM spur. The bridge over the 401 will be enhanced to carry a second deck or span for a second track specifically for the passenger trains. Immediately to the north of the 401 the CP track drops slightly and the new passenger track will rise over the top separating operations."
"The track will then drop and head east towards Bowmanville parallel to the CP track."
(I couldn't find any pictures of an elevated passenger train track from a bridge over a highway going over a freight train track, but thought I'd add a picture below for a visual of sorts.) Imo, it is difficult to imagine the aesthetic of the GO track rising over the 'top separating operations', which I assume means overtop of the CP freight track, because of what Metrolinx described.