hsr_fan wrote:How difficult/expensive would the interchange at Monmouth Junction be? Could it be built without interfering with 135 mph Acelas and all the other high speed traffic? Could the NEC handle the additional traffic from Monmouth Junction to Newark? (Where would these diesel trains terminate? Hoboken?)
It would be expensive and difficult, because it would require some grade separation (a tunnel under the NEC in the westbound direction); it wouldn't necessarily interfere with Acela traffic because the turnouts would be from Tracks 1 and 4, while Acelas generally operate on Tracks 2 and 3 in that area (hence the requirement for grade separation - to keep the westbounds from having to crawl across the whole plant to get to the MOM line, blocking traffic on all four tracks).
Some consideration would have to be given to allow the use of high speed turnouts to and from Tracks 1 and 4 (with enough length in the "leads" so that westbound trains could exit the NEC at high speed and slow to the curve speed before ducking under the NEC, and eastbound trains could get up to a respectably high speed before merging onto Track 1).
In addition, the area there is fairly "wet", which will require some more expensive tunneling techniques, and a watertight tunnel.
The NEC could theoretically, with the grade separation in place, and a new, higher speed switch-equipped Midway Interlocking, handle the extra traffic. But that doesn't take into account the proposed ARC volumes on the NEC, which will be quite dense.
The latest documented thinking on where the trains would go on the east end is Hoboken, the MMC, and possibly a reconfigured Hudson Pocket.
hsr_fan wrote:Theoretically, I agree that this is the best route. But if the costs are too high, I wonder if the Red Bank option might be a more realistic approach. The problem there is that it misses Freehold, and a spur out to Freehold might be too indirect.
I'm sure the folks at NJ-ARP will disagree, but the NJT website actually shows the Matawan alignment generating the most ridership, with the lowest end to end travel time, the lowest estimated cost per mile, and the second lowest annual operating cost estimate.
It remains to be seen whether or not *that* particular alternative is chosen as "locally preferred". Should be an interesting few years coming up.