How to build a great big underground railway....

[Dartzap]

New documentary about the building of Crossrail in (under) London which was on BBC2 over the last few weeks, has a fair amount on engineering, history, trains and architecture to keep most of you amused for a few hours. Its not immensely detailed, but it does what it does well enough.







The most impressive bit for me is the vast scale of Canary Wharf station. Will definitely have a mooch through there when its up and running in a few years.

[Siege]

Very cool to watch. The third part didn't come in HD and there were some odd audio issues here and there, but it's seriously impressive to see the amount of engineering that goes into a project like this.

[Thanas]

In contrast, I would love to see a documentary on how you can mess such a project up, like the Roman Metro 3 that has been stuck in the same place for several decades now.

Well, stuck is a bit unfair, they managed to finish about everything outside the city, whereas planning inside the city centre has not even started.

[Alferd Packer]

Or the Second Avenue Subway in Manhattan. They've been trying to get this done for like 85 years now. Fortunately they've actually been making progress in recent years and could have something up and running by the end of 2016.

[Starglider]

Heathrow to central London will be extremely useful, Picadilly line is horribly slow, bit of a blow to the Gatwick second runway campaign though. Liverpool Street to Canary Wharf will certainly be useful; DLR is ok but pretty slow. Commuting from the western commuter belt to Canary Wharf / east end will actually become practical, Waterloo -> Waterloo + City Line -> Bank -> DLR -> Canary Wharf is just too much.

[Simon_Jester]

What are the big obstacles that slow such construction down? Off the top of my head, I imagine one problem is trying to figure out how to dig safely through areas that are heavily built up, in which case you're going to encounter all sorts of poorly documented underground structures and infrastructure.

[Teebs]

What are the big obstacles that slow such construction down? Off the top of my head, I imagine one problem is trying to figure out how to dig safely through areas that are heavily built up, in which case you're going to encounter all sorts of poorly documented underground structures and infrastructure.

As I understand it, that was a very real problem with a city as old and heavily built upon as London. Other problems that spring to mind are more logistical rather than engineering problems - getting planning permission, funding etc. Those took up a good chunk of time. On the engineering side, how fast your tunnel boring machines can safely go must be a significant factor.

[Thanas]

What are the big obstacles that slow such construction down? Off the top of my head, I imagine one problem is trying to figure out how to dig safely through areas that are heavily built up, in which case you're going to encounter all sorts of poorly documented underground structures and infrastructure.

The main problem in Rome is that they (against all advice from archeologists) ignored just how old and deep Rome is, thus they have to stop every five centimeters for another archeological rescue dig. Sure they could ignore all that and just press on but a) not good for publicity and b) a lot is just accumulated ancient trash, which means that unless they are very careful it will all collapse, with possibly the entire forum going under.

You imagine being the guy who destroyed the center of European civilization (as well as the economy of the city of Rome/Italy) and then consider if you would like to take that chance.