I was surprised to hear tunnel boring was to start next year. I thought some NJ towns were still fighting the tunnel.
I think that’s just for the portion of tunnel under the Hudson River itself. Much of the approach tunneling on the Jersey side has been in process for years (yes, with objections from local political reoresentatives).
I lost interest in this boondoggle when it became a longer, curvier, vastly more expensive way to add two more tunnel tracks to the same line west of the Palisades. It was supposed to be a high-speed connection…
I suspect part of the reason it is so curvy is these days there is so much buried infrastructure under Manhattan. Additionally part of that island is fill and other parts are former swamp which makes any underground boring challenging as they probably need to avoid a lot. Earlier when the original bores were done, there was probably a lot less buried infrastructure and they had more choices open to them.
On this same subject, I have to say I am amazed it has taken CSX the better part of 6-8 months to figure out how to lay a layover track in Mobile, Alabama for the new Amtrak service to that city. I heard the challenge there was the similar. Underground infrastructure in which the above ground track might impact. So based on what I read they had to map everything out in advance as well as relo some items underground before even getting to the track plan.
None of the current Gateway is curved under Manhattan; the “box” under the Yards reflects the original approach curve from the south when it was still part of a high-speed line relocation, and it is far west of major infrastructure on Manhattan. (See the history of the #7 train extension.)
The current curve is under New Jersey, and I believe most of the work is hundreds of feet down in the rock of the Palisades, a volcanic dike, where there will be little or no infrastructure to avoid or relocate.
Now, the current whackdoodle idea of adding a bunch of new stub-end platforms south of the existing trackage – that definitely involves a bunch of existing concerns. But that is not really a ‘Gateway Tunnel’ issue (and was common to the aborted ARC project).
From what I understand the original idea behind preserving the “box” was new building foundations being approved would have blocked that approach within x amount of years so they wanted to get it reserved for Amtrak’s future tunnel.
Yes, but that doesn’t explain why the box they built curves to the south instead of going straight parallel to the existing North River Tunnels.
Without KNOWING the subterrarian conditions being encountered one has no idea of why any particular routing decision was made - those conditions include utilities as well as ground conditions.
Four alternative routes for the NJ side were considered in the EIS. The sticking point was the tunnel ventilation shaft building. The three shorter alternatives all had existing development, all which would have cost extra in money and time, so the fourth alternative was chosen.