The key to making this work is that the 125th Street SAS station be deep enough to allow bored tunnel underneath 125th Street. A major impediment would be sub-surface water in the form of an old stream and a high water table; this has been a big problem with the Lenox Avenue subway for 103 years, and all the steps taken by the IRT engineers to waterproof that tunnel weren’t enough.

This would help making existing infrastructure i.e. the GWBBT, more highly utilized by not only giving it two, possibly three, more lines of subway service (C, T, possibly 1) but also by giving it direct access to the east side.

Rail to LGA should be a cinch; an AirTrain-like viaduct for subway service in the median of the Grand Central Parkway would cause minimal visual or audible impact to the host communities. It could diverge from the Astoria Line just south of the GCP and run as a loop through LGA. Alternatively, run it as a spur from the Amtrak Hell Gate Line, with conventional rolling stock if need be. Baggage could be checked through from Penn Station – imagine that! The service doesn’t have to be a flashy thing like the AirTrain, much as I like it – SEPTA runs regular commuter rail from Center City to the Philadelphia airport – right to the terminal.

Conventional rail from Penn Station to JFK was proposed in the 1970s, the key component being rehabilitation of the LIRR Rockaway Branch and construction of a spur from Howard Beach to the airport terminals. It might have happened except that there was no money for anything then, and people living near Forest Park thought the trains going along the old right-of-way would imperil people. That problem was solved in Riverside Park in the 1930s by roofing over the railroad tracks. While the right of way is largely intact, the AirTrain makes that option no longer viable. As a practical matter, any Manhattan – JFK direct rail would have to utilize the AirTrain alignment, perhaps with different rolling stock. Having the AirTrain and conventional rail share tracks would be tricky but not impossible; the train control and signaling systems are different and the current AirTrain rolling stock isn’t built to FRA crashworthiness standards.

I agree that the Second Avenue Subway needs to run up to Co-Op City. For this line to relieve the Lex in any meaningful way, it must run to the Bronx. There’s ample room along the Northeast Corridor from the Hell Gate Bridge to past Pelham Parkway to do this. A transfer station to the 6 at Hunts Point Avenue would complete the picture. The MTA’s Penn Station Access Study (check the MTA Web site) has some good stuff on this, from the point of view of running Metro-North service along the line, but it is understandable at least as well in subway terms. And maybe running it to Staten Island is the answer.

Beyond all this, I suppose my wish list is to build the IND Second System (most of it, anyway) plus a line in the median of the LIE, but barring that I’d like to see a lot more intra-City service on the commuter lines, esp. in NE Bronx and much of Queens, and BRT in a big way. And try to make the whole system less Manhattan-centric.

Long term, I think the suburbanization of America (subsidized car culture) is dead. The negative environmental effects are one reason, but more importantly, the era of cheap oil is gone forever. Regardless of new discoveries or mileage gains, the China/India/Brazil, etc. genie can’t be put back in the bottle.

Also, i am 100% confident that the Dems will take both houses of congress and the presidency in 2008. They will inherit a fiscal mess from the current clown college faculty running the federal government. . . quite likely, a nasty recession as well.

Perfect opportunity for a new WPA (my fantasy) and in any case, more funding for transit and equally important, freight rail. I think we’ll have a carbon tax at some point, or at least increased gas taxes as there is a push to make the cost of driving better include its externalities.

We’ll see what happens of course. But I like the expanded list a lot better!

But if I were going to look at the subway map and say that I could add any number of things between now and 2108 – outside, of course, the F express – I think I’d go with this:

1. Full Second Ave. Subway from the Bronx to Staten Island. The train should terminate past the 6 at Co-Op City, run down Manhattan via Second Ave. and run under the harbor at higher speeds to Staten Island. SI really needs that subway, and that addresses one of your desires.

2. Fully integrated airport access: High-speed raillink from JFK to Manhattan; rail connection to LaGuardia. I think right-of-way and construction costs will be prohibitive.

3. Extending service out past Flatbush Ave. Bergen Beach, Mill Basin and parts of Canarsie are woefully underserved by the subway.

4. Brooklyn-Queens service running into northeastern Queens. Another crosstown connection could two needs at once.

5. Cross-Bronx subway service. This probably wouldn’t happen either, but it sure would be nice.

The problem with all of these dreams however is that rare are the days when someone picks up the ball for major Public Works projects. These five proposals including the ones you mention would require some major expenditures and foresights. But they all will become necessary pretty soon.

I’ll raise you a connection to Staten Island, a combination of the regional commuter lines (LIRR, Metro-North, AND NJ Transit), a combination of PATH and MTA subways (sooner than you might think now that there is fare parity) and additional trans-Hudson tubes (at least one new Hudson crossing in addition to the THE Tunnel).

Subway access to LaGuardia, including a link from LaGuardia to JFK.

Also: ubiquitous video surveillance in subway cars and stations.

And of course, the F Express / V local to Brooklyn!