Amtrak Gateway Tunnels

Will there be space in the tunnel boxes under hudson yards for more than 2?

mtuandrew wrote:

a new PATH line, 33rd St - Weehawken - Secaucus/Meadowlands

Why would people get off a fast train to Manhattan to get on a slower train to Manhattan?

Greg Moore wrote: That said, it may make a bit of sense to design a lower level that after hours could run freight to Long Island.

They want to divert enough freight from trucks that it makes sense to build two tunnels between Jersey City and Brooklyn.

Jeff Smith wrote:a myriad of connections not available at Penn such as LIRR (upon ESA completion),

The LIRR is still going to serve Penn Station after East Side Access opens. Why would somebody change in New Jersey to a slow train to Grand Central when they could take a fast train to Penn Station and change to the LIRR there. They'll be able to change to Hudson and New Haven line Metro North trains at Penn Station too.

rr503 wrote:Will there be space in the tunnel boxes under hudson yards for more than 2?

No

The next set of Amtrak tunnels ( year 2080 ) under the North ( Hudson ) river may be farther north to go directly to Grand Central Terminal and on to the Hell Gate bridge.

Greg Moore wrote: (and Amtrak has little reason to go to GCT and that's a weird way to get to Hells Gate btw).

it's served by the busiest subway line in the country. It carries more people than than any other system in the country. And the Flushing line.

If they want to use the Hell Gate line for subway service and freight to New England and Metro North service there's no capacity for intercity trains and they have to dig a tunnel from the vicinity of New York/Connecticut border to Rahway or New Brunswick. Or some tunnels on Long Island and a long trestle to New Haven.

DogBert wrote:

Backshophoss wrote:The BIGGEST red flag is the PCB layer in the Hudson River bottom,so a dredge,sink a tunnel section,and then cover,
will require some form of EPA oversight/permitting,may become a nightmare.
Drilling a tunnel bore may be the only option,but with "steeper" grades as the trade off to the PCB cleanup problem.

Knowing nothing about PCB removal, I'm wondering how much is down there and how much it would cost to remove a streak of it cutting across the river.

PCBs in sediment are like asbestos in your house: if you have it, you really, REALLY don't want to disturb it. You start digging around in that, the tidal currents in the middle of the river channel will wash it all over New York Bay. Litigation alone would cost a fortune.

Why reinvent the wheel? Why wouldn't new North River tubes be built the same way as the current ones, which have lasted pretty well for a hundred years.

Adirondacker wrote:

Jeff Smith wrote:a myriad of connections not available at Penn such as LIRR (upon ESA completion),

The LIRR is still going to serve Penn Station after East Side Access opens. Why would somebody change in New Jersey to a slow train to Grand Central when they could take a fast train to Penn Station and change to the LIRR there. They'll be able to change to Hudson and New Haven line Metro North trains at Penn Station too.

That's a good point on LIRR, but you completely omitted my other points by truncating a complete sentence in my post that also mentions MNRR and other subways. Don't take me out of context. As for slower? Perhaps. Maybe they won't want to deal with Penn. Maybe they're meeting someone at GCT. But your point on the availability of LIRR at Penn continuing is well taken.

Swooping down to 18th Street or so, stopping at 23rd, 34th, Tenth Ave, Times Square and Fifth Avenue takes time. It will be faster to go to Penn Station go one stop to Times Square and take the shuttle. Or in 2050 just stay on the suburban train through Penn Station and get off at Grand Central.

There are subways that serve Penn Station that serve stations on the East Side.

Clearly it appears that Amtrak does not want another tunnel digging through the sediment in the river, but would rather have it in bedrock. I can understand why bedrock is good (solid, nothing moves), but do the existing tunnels really move much? How much up and down or left to right is there when a train goes through or when the tide moves? If there's a fair bit of movement then I'm sure that's helping the deterioration of the tunnels.

I have seen pictures of a submerged tunnel tube that is suspended off the bottom. (possibly Honshu , Japan). If sediment disturbance is such a issue, perhaps a canterlevered submerged tube would be a quicker answer. Would reduce the gradient as well.

There are lots of trans-Hudson tunnels, vehicular and railroad. Although the movement of the tubes in the mud worried the Pennsy engineers, it turned out not to be a problem. As far as I know, the only problem is damage from Sandy, which was caused by water getting in, not by the tunnels' movement. There is no practical way to anchor any trans-Hudson tunnels in bedrock, but it is also not necessary. (There are, incidentally, bedrock tunnels crossing the Hudson north of NYC. They are the Catskill and Delaware aqueducts. They are several hundred feet down, but since they contain only water under pressure, vertical shafts were used. Obviously that won't work for a railroad tunnel.)

As I've stated previously, Gateway will be a shallow-cover tunnel, with a minimum cover of less than 20 feet between the tunnel crown and the river bed. Bedrock in this part of the Hudson is WAY too deep - about 150 feet below mean low water at the NY Bulkhead Line.