I have 1 question about your numbers: Why the 1.5km of tunnel? The Sheppard Subway tail track extends almost all the way to Senlac (vehicle storage). Presumably, it could surface within a couple hundred metres from there, before the West Don bridge. That lowers the cost substantially right there.
Originally Posted by Rainforest
Also, I think the conversion shouldn't necessarily be counted as just part of the Sheppard-Finch link. Personally, I think that should happen even if the two aren't linked up. It should be a one-seat ride from Scarborough to Yonge.
The way that I break it down is this:
Sheppard East and Finch West LRTs: already funded (not included)
Sheppard Conversion: $670 million
Sheppard West extension: $200 million for the at-grade (3 km), $100 million for the portal, $100 million for the bridge widening
Sheppard-Finch link: $260 million (4 km of at-grade)
I think the Sheppard West link and conversion should happen anyway, so really the stretch that's in question is the $260 million for the link between the two lines. You're building about 6 km of at-grade (plus a tunnel into Finch) in order to go from Finch West to Finch stations via Finch, or 7 km of at-grade to go from Finch West to Sheppard-Yonge (plus about 100m of new tunnel).
Building an extra 1km of track in order to get a true northern crosstown seems like a good deal to me.
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