Second Ave Subway Construction thru Phase I open

I would think it would have been wise to construct the SAS with the option of adding express tracks later (after all we don't need another IRT Broadway line, BMT Broadway line or Canarsie line). However, the trouble is with the methods used -- you can't just make the tunnel wider with a TBM like you can with cut-and-cover. It's a shame though -- but perhaps with the wide spacing and the CBTC system it'll run fast enough without expresses.

Which Broadway? JMZ or NQRW?

The J/M/Z. I think all long routes should have been built with express tracks.

Oh. I get them confused. Besides, they both use montague street tune;z
(note the time that i;m wruting thids at)

JayMan wrote:The J/M/Z. I think all long routes should have been built with express tracks.

Unfortunately, even though the Jamaica El was built with provision for a center track, it was not installed when they added all the other express tracks on the other dual contract els.
Out of all the dual contract els, Jamaica is probably one of the ones that needed it the most (probably only the 7 line needs it more). It's sort of ironic that it was the only one that didn't get it (aside from the Livonia el, but that one doesn't need it anyway).

This proposed two-track line, from 125 St. to Hanover Square is already obsolete. What makes these engineers think that this line will be useful in 30-50 years? As far as I know, anything less than 4 tracks under Second Av. (between 125 St. and Houston St.) is an abomination.

The planned SAS is designed to run 30 trains/hour in each direction. That level of service should be more than sufficient for the line without having to have to add express tracks. The two track line will have numerous cross switches and a few stations will have 3 tracks.

I agree that with modern technology i.e. signaling and such, the 2nd ave subway will run more frequently and efficiently than a local on some of the other lines and given this country's seeming scorn of mass transit (or belief that its not new and modern like the car, a device which has had not reasonably revolution in technology since the auto trasmission, forgive my tirade) a two track line is an economic reality. However, I feel that first of all the form of construction they are using will take longer than necessary, and they are wrong to not even put in the provision for express service. It makes sense the only build what u can afford, that's why they're building it in incriments. However, they are doing an incredibly diserve by not adding provisions. They did that on the 63rd st subway and that's how the upper 2nd ave line will be able to connect with the Broadway line. Thinking ahead is essential. On the bright side of things, it may not be impossible to add express service later on, despite not planning for it. The Manhattan bridge was not designed to connect to the IND, but it was redone to do so. We can always hope.

To quote those well-known transport planners Jagger & Richards:

"You can't always get what you want...
but if you try sometimes, you just might find..
You get what you need!"

which is a reasonable subway on the upper east side.

This is nowhere near the abomination that is the AirTrain JFK (when they could have stood up to the NIMBYs and put a line through the old LIRR Rockaway ROW). I think the capacity will be sufficient and the headways very short with modern signalling. Let's get it built!!

True, and I agree. But I can still complain, right? I mean New York State has had some pretty crappy transit governance for a while. Yes, something will be better than nothing for the Second Avenue Subway. Further, I'm only complaining that they are leaving no provision for express service. Not that they are not getting it now. I cannot imagine that such provisions would be prohibitively expensive. On the plus side, maybe future engineering will be capable of moving past this oversight.

It would be prohibitably expensive because the are using deep tunnel boring for the new subway tunnel unlike the the cut-and-cover method that was used for the rest of the subway -- when using cut-and-cover widening the tunnel for 4 tracks added only marginally to the construction costs, but with a TBM the cost goes up rapidly as you make the tunnel wider.

The could add express tracks in the future, but if they do that it will have to be on a lower level like the upper Lex Ave line.

That's exactly what I mean...to a point.

To be fair, I fail to understand why they are using TBM at all. Building the city's third water tunnel, or a line under the rivers is one thing, but under Second Ave seems to be an attempt to increase the amount of time it will take to build it (and the amount of time lapsed goes up, so do the bills). However, they didn't ask me (Why is that? LOL)

Anyway, by provisions, I don't mean widen the tunnels neceessarily. That would be ridiculous. However, they could veer off the TBMs a little so there are curve offs for spurs to an express line.

I have to admit, however, that while at the moment it seems unlikely that express will be added. The plans laid out on the MTA's website, indicate to me that in order to build express tracks, the MTA would just have to build another set of tunnels along side the existing ones and reconfigure the stations that would become express (or the ones taht would become local) depening on how they wanted to do it. But given the projects already and nearly prohibitive price tag, we'd need a major policy shift nationally in order to do it. But hey, we can dream, right?

Remeber, cut and cover would be <b>severely</b> disruptive to surface traffic during construction.

That combined with a vastly increased exposure to liability from construction (close proximity to pedestrians, construction much closer to building foundations, etc), it's really no surprise that TBM is the preferred method of tunnelling under cities these days.

Look no further than Boston for an example of how disruptive cut and cover can be.

Boston is vastly different and due to its crummy soil, and deep bedrock, TBM tunnels would collaspe behind it. Recall the I-90 connector to the Ted Williams.
Anyway, I guess your right, but I still don't have to like it. Oh, well, they never listen to me anyway.