Quote:
Originally Posted by jmecklenborg
That's part of it, no doubt, but the design wasn't going to be 4 side-by-side tracks for 40~ miles. There were going to be spots where HSR would be elevated/depressed but Caltrains would remain at-grade in part to save money and in part because there are still active freight spurs and the light rail line in Mountain View.
I think we're going to see full grade separation of HSR revisited when the Transbay approach tunnel is funded and the second Transbay crossing is under study. It's not difficult to see, when scanning the line on Google Earth, that there is plenty of space for the HSR tracks in most locations to run at-grade. Where conflicts exist it'll be a lot easier, in some places, to leave Caltrains as-is and build HSR tracks on piers directly next to the existing tracks or directly above.
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Americans understand the bidirectional 3 or 4 track rail corridor easier because of the NEC, but the English quad track layout used to have both a fast pair of up and down tracks and a slow pair of up and down tracks, which would be very similar to having a regular sets of tracks for regular trains and a separate set of dedicated high speed tracks within the same corridor.
The operational advantage of the NEC quad track configuration is that freight industries can exist on both sides of the corridor and be serviced easily with little to no impact to fast trains on the fast tracks. The English configuration favors placing industries along the slow pair of tracks on one side of the corridor, to reach industries on the fast side of the corridor flyovers or duck-unders are needed, all adding to the expense to build and maintain the corridor. In a market where the corridor is maintained by private enterprises, flyovers and duck-unders are not preferred. In a market where government maintains the corridor, flyovers and duck-unders are just another cost for taxpayers to subsidize.
On the Peninsula, Caltrains already owns the corridor, so either quad track layout would have worked. I strongly believe the nose abatement issues were the primary reasons for the preferred alignment chosen in the EIS. As with the rest of the CHSR lines, reducing costs have not been, are not, nor will not be the primary concerns of the Authority.