BurlOak
Senior Member
So I figured out how to solve this. Build it roughly as shown, or maybe slice off one lane (make it temporary a 3 lane bridge with middle lane alternating) of the existing bridge and move new bridge a bit east. The railway would be underneath, and the roadway on top - thus, the roadway would be at a higher elevation than current - about 5m. The roadway would carry 3 traffic lanes - 2 SBL and 1 NBL for people coming out from the hospital. The existing bridge would be rebuilt as 2 lanes for the main NBL of McCowan. This bridge would be at the existing elevation. Now the Benleigh Drive intersection would meet a McCowan Road at the same elevation as now, but only right turns (northbound) are allowed.The key to cut-and-cover is to find a way of handling the hospital. I sketched up an B-D line that is just west of McCowan (note that North is right). Google Earth elevations are not that accurate, so I am not sure if things are correct. Once you clear the hospital, everything else can be cut-and-cover - unless you want to go to Sheppard than TBM is required under 401).
The Station is underground at Lawrence, but extends north and becomes roughly at (near)-grade as McCowan dips about 3.5%. The subway would be on a bridge, about the same elevation as McCowan. After crossing Highland Creek, the line would go underground and curve to continue north under McCowan. I have now blocked access to the hospital, so that needs to be worked out.
I would have loved to raise the elevation of McCowan and just put the subway under the bridge, however, the line would not be underground in time for Benleigh Drive and access to that road would be blocked.
View attachment 102350
So if you are heading southbound, there are 2 lane on the new "high level bridge".
For those coming north, the exit to the hospital in on the left, and traffic rises to be on the "high level bridge". A left turn is made to enter the hospital.
For those coming north and continuing north, they would take the right 2 lanes and use the "low level bridge".
For those coming from the hospital to head north, they would make a left onto the "high level bridge" and continue on this.
At the north end of the bridges, between Benleigh Drive and Bellechase, the 3 lanes would go into 2.
View attachment 102350