3 ms·

In contrast, the 2 mile long SR-99 tunnel under Seattle cost $3.3 billion, whereas this is 55km for $11 billion. I.e. in Europe they're tunnelling for $0.2 bil

by pacaro 5y ago

In contrast, the 2 mile long SR-99 tunnel under Seattle cost $3.3 billion, whereas this is 55km for $11 billion. I.e. in Europe they're tunnelling for $0.2 billion per km compered to the US at $0.97 billion per km.

bombcar 5y ago
Amusingly tunneling through the Alps may be easier and cheaper than tunneling through a city.
- cfraenkel 5y ago
  No NIMBY on the top of a mountain
- jmyeet 5y ago
  I present to you the Second Avenue Subway [1]: > The $6 billion price tag for phase two works out to $2.2 billion per kilometer. That would make it the world’s most expensive subway project on a per-kilometer basis, narrowly surpassing phase one of the Second Avenue Subway, which clocked in at “only” $1.7 billion per kilometer. Let's compare that to Crossrail, which goes under London, a 2000+ year old city notorious for hitting Roman ruins where the only real solution is to dig deep (ie even more expensive) [2]: > Crossrail was built in the heart of London to similar standards to New York Projects at $500M per mile. [1]: https://www.vox.com/policy-and-politics/2017/1/1/14112776/new-york-second-avenue-subway-phase-2 https://www.vox.com/policy-and-politics/2017/1/1/14112776/ne... [2]: https://tunnelingonline.com/why-tunnels-in-the-us-cost-much-more-than-anywhere-else-in-the-world/ https://tunnelingonline.com/why-tunnels-in-the-us-cost-much-...
- waiseristy 5y ago
  Not only that, but a city that is predominately built upon silt and backfill
- pacaro 5y ago
  Definitely tunnelling through rock is a more straightforward proposition. Bertha famously hit an allegedly uncharted steel pipe part way through and had to have extensive repairs. Clearly tunneling under a city is a very different proposition from tunneling under a mountain range. And I'm willing to bet that a significant part of the cost is not per km, nonetheless it's just another example of the crazy cost of civil engineering in the US
  - bombcar 5y ago
    Heh I wonder what percentage of the final costs of these things is simply worker healthcare. I suspect the UK/Euro ones don’t have to account for that as that’s handled elsewhere.
cinntaile 5y ago
Another recent datapoint is the tunnel between Germany and Denmark has a budget of €10 billion for 18km so €0.55 billion/km. Projects like these tend to have budget overruns, so maybe €15 billion? That'd be €0.85 billion/km. But that's completely ignoring any geological differences of course, so not very realistic.
- Archelaos 5y ago
  > But that's completely ignoring any geological differences of course, so not very realistic. I could imagine that there are several other features of a tunnel that might affect its price considerably: cross-section dimension, number of pipes, technique of construction, security installations, ventilation, the type of use (rail, automotive, both), ... For example, the Fehmarnbelttunnel/Femern Bælt-tunnelen you mentioned will consist of four pipes for both, rail and automotive, and is not drilled but built out of prefabricated modules (42m x 9m x 217m) made of concrete placed in a trench on the seabed and then covered with stones and sand.[1] [1] Source: https://de.wikipedia.org/wiki/Fehmarnbelttunnel https://de.wikipedia.org/wiki/Fehmarnbelttunnel (in German)
vlovich123 5y ago
I think you got the US value slightly incorrect. 3.3 billion / 2 mile = 3.3 billion / 3.218688 km That’s $1.03/km, no?
- pacaro 5y ago
  Probably, I was lazy in my miles to km conversion. I assume the distances aren't on the nail anyway, so probably $1b/km is the reasonable number in this context

by pacaro 5y ago

bombcar 5y ago

Amusingly tunneling through the Alps may be easier and cheaper than tunneling through a city.

cfraenkel 5y ago
No NIMBY on the top of a mountain
jmyeet 5y ago
I present to you the Second Avenue Subway [1]: > The $6 billion price tag for phase two works out to $2.2 billion per kilometer. That would make it the world’s most expensive subway project on a per-kilometer basis, narrowly surpassing phase one of the Second Avenue Subway, which clocked in at “only” $1.7 billion per kilometer. Let's compare that to Crossrail, which goes under London, a 2000+ year old city notorious for hitting Roman ruins where the only real solution is to dig deep (ie even more expensive) [2]: > Crossrail was built in the heart of London to similar standards to New York Projects at $500M per mile. [1]: https://www.vox.com/policy-and-politics/2017/1/1/14112776/new-york-second-avenue-subway-phase-2 https://www.vox.com/policy-and-politics/2017/1/1/14112776/ne... [2]: https://tunnelingonline.com/why-tunnels-in-the-us-cost-much-more-than-anywhere-else-in-the-world/ https://tunnelingonline.com/why-tunnels-in-the-us-cost-much-...
waiseristy 5y ago
Not only that, but a city that is predominately built upon silt and backfill
pacaro 5y ago
Definitely tunnelling through rock is a more straightforward proposition. Bertha famously hit an allegedly uncharted steel pipe part way through and had to have extensive repairs. Clearly tunneling under a city is a very different proposition from tunneling under a mountain range. And I'm willing to bet that a significant part of the cost is not per km, nonetheless it's just another example of the crazy cost of civil engineering in the US
- bombcar 5y ago
  Heh I wonder what percentage of the final costs of these things is simply worker healthcare. I suspect the UK/Euro ones don’t have to account for that as that’s handled elsewhere.

cinntaile 5y ago

Another recent datapoint is the tunnel between Germany and Denmark has a budget of €10 billion for 18km so €0.55 billion/km. Projects like these tend to have budget overruns, so maybe €15 billion? That'd be €0.85 billion/km. But that's completely ignoring any geological differences of course, so not very realistic.

Archelaos 5y ago
> But that's completely ignoring any geological differences of course, so not very realistic. I could imagine that there are several other features of a tunnel that might affect its price considerably: cross-section dimension, number of pipes, technique of construction, security installations, ventilation, the type of use (rail, automotive, both), ... For example, the Fehmarnbelttunnel/Femern Bælt-tunnelen you mentioned will consist of four pipes for both, rail and automotive, and is not drilled but built out of prefabricated modules (42m x 9m x 217m) made of concrete placed in a trench on the seabed and then covered with stones and sand.[1] [1] Source: https://de.wikipedia.org/wiki/Fehmarnbelttunnel https://de.wikipedia.org/wiki/Fehmarnbelttunnel (in German)

vlovich123 5y ago

I think you got the US value slightly incorrect. 3.3 billion / 2 mile = 3.3 billion / 3.218688 km That’s $1.03/km, no?

pacaro 5y ago
Probably, I was lazy in my miles to km conversion. I assume the distances aren't on the nail anyway, so probably $1b/km is the reasonable number in this context