Further to my
Jan 2004 Study Summary, here's a not so brief summary of the Feb 2006 report wrt to the SE. I imagine this post won't be terribly easy to follow as it's really just a collection of things that jumped out to me while I was particularly looking for info on the 2nd St SW alignment, and for a general sense of what "studied to death" has actually meant. Just an interesting snapshot from 2006 when the current alignment first took root.
There's a lot going on here, but one thing I found crazy is that the red option 3A involves an elevated crossing over the tracks, a surface station between 9th ave and the CP tracks, and then a deep bored tunnel to Centre St. So...that's just kinda nuts compared to just tunnelling, right?
Analysis was first on the broad concepts, with the beltline as the obvious choice
The cost numbers here seem interesting. Option 1 seems to include costs for the 8th Ave Subway - I'm guessing that's for a TBM the full length? Option 3 involved both elevated and a TBM. But below the beltline options are in the $250M-312M range...
I was hoping to find more reasoning behind the 2nd St selection, but it seems it's as simple as 2nd > 6th. It's fairly easy to see why those are the two options at the time, especially since they proposed cut and cover tunnel for 2nd St SW, which involved demolishing and rebuilding the ramp on the north side of the tracks. So from that standpoint I completely understand why 2nd was a natural choice. I would be curious what the ramp demolition/rebuild costs and impacts were.
One of the 10th Ave concepts seems to have involved crossing Macleod Tr at grade and then tunneling under 1st St SE...which is weird:
But largely the focus was on determining the E-W alignment in the beltline, landing on 10th Ave
It may be hard to see, but it's neat that they included provision for a bike lane alongside the tunnel. It's not exactly clear to me where the tunnel approach begins, but it all seems impressively tight.
Overall a really interesting report (with a lot more good stuff about the north and west lines). However, it doesn't seem there was much focus at all on the CP tracks/8th/7th, at least not from a beltline approach. No mention of any conflict with 8th Ave subway (again I wonder if the assumption - perhaps at the convenience of this report's conclusions - was deeper TBM?). At this point there are no significant concerns with running at-grade in the beltline (though they do list the challenges involved).
I'm sure I'll get there in subsequent reports, but can anyone share why the cut+cover idea on 2nd was dropped (and presumably has remained untenable despite the cost issues)?
TLDR: the alignment was arrived at presuming at-grade through beltline and then cut+cover running N-S. No consideration to elevated or TBM on a beltline alignment at this time.