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Posted Sep 23, 2011 11:05 UTC (Fri) by Trelane (subscriber, #56877)
Per capita clearly (to first order) is going to trend lower with lower per capita levels of car ownership, and I'd guess that the us has much higher rates of car ownership than those countries. Per length is murkier; it would be lower with longer unpopulated distance, but driver effects like highway hypnosis and driver fatigue would counter that.
Posted Sep 23, 2011 18:40 UTC (Fri) by dlang (✭ supporter ✭, #313)
I agree that per mile stats are a far better picture of real risk than per capita stats.
This is a large part of the reason why public transportation doesn't work well in the US.
Public transportation works well if you have a very dense population center that you can saturate with public transportation. New York City is a great example of this with it's subway grid.
It also works well if you have a major work area with an outlying population and can have radial feeds into the downtown areas. Cities that grew up around a single major factory complex or who have a huge amount of downtown business skyscrapers meet this criteria.
but everywhere else, the cost of building public transportation Infrastructure (and then running it) that would be able to get everyone where they need to go with both a decentralized worker pool and a decentralized work area is so high that it is impractical. And as soon as people start needing to have their own care to get to some of the places they need to go routinely, the marginal cost of using that car to go elsewhere is small. As a result it becomes more cost effective to upgrade the road grid than to build enough public transportation to eliminate it.
Posted Sep 23, 2011 18:55 UTC (Fri) by martinfick (subscriber, #4455)
I doubt this is actually true. I think most people underestimate the real recurring costs of roads and cars put together. In fact, I suspect that is the real reason they are the primary transportation mechanism in the US: more expensive roads and the need for cars / gas makes more businesses dipping into the pie needed to support this infrastructure. This in turn means more political clout. It's a pretty safe bet in the US (not ruling anywhere else out here) that any solution to any problem which costs more will likely be adopted by political parties (and pushed by businesses/interest groups).
Posted Sep 23, 2011 19:14 UTC (Fri) by dlang (✭ supporter ✭, #313)
railroads are very expensive to build, but (on a per-ton-mile basis) very cheap to operate.
but if you don't have a lot of cargo/people to transport the ongoing savings won't catch up with the initial infrastructure costs.
bus transportation is cheaper in that it can use the same road infrastructure as cars do, but you have to pay the driver and vehicle maintenance even if you don't have any riders. Bus service is also significantly slower than personal car transportation.
I lived in the greater Los Angeles area for a little over 6 years without having a car. During this time I lived pretty close to bus routes (within two blocks of both north/south and east/west routes). It can be done, but it's very inconvenient.
Posted Sep 23, 2011 19:34 UTC (Fri) by martinfick (subscriber, #4455)
I don't even buy that. They utilize way less land than roads do. Even a massive high speed rail is thinner than a small neighborhood road. The steel is likely the only really high ticket item.
You have to also think about what you are comparing. It is not fair to compare RRs designed for interstate freight traffic to local roads. If RRs were to be used for more local transportation, they would have scaled down by now to something that would not be recognizable as normal RRs. There would be much lighter weight rails than what is even considered light weight today. We would be using very small gauge rails to run through our neighborhoods. The cost of these would be significantly less than those of major RR lines today.
Oh, and it really doesn't help to use he word "public" in any of this conversation. Roads are just as public (or not) as rails/buses/trains. All are mostly funded by taxes. It is not a good differentiator when comparing transportation modes.
Posted Sep 24, 2011 2:16 UTC (Sat) by dlang (✭ supporter ✭, #313)
don't discount the cost of the rails, over miles that really amounts to a large amount
also, all the control points where other traffic needs to get stopped to let the railroad go through cost
then you have the need to engineer specific places where the traffic can be redirected (switches, etc)
what makes railroads efficient to run is that they have very low friction, and as a result you can pull the same load with less power. As a result of having lower power for a given weight (and less friction with the tracks), trains accelerate slower than normal vehicles. due to less friction, they decelerate slower as well. As a result you want to avoid having the train make speed changes as much as possible
if you are going to stop frequently (and don't have a huge volume of passengers that need to fit in each vehicle), then dedicated busways (2 lane roads usable only by buses, with railroad like crossing guards) are actually cheaper, and the buses can leave the busways and use normal streets as well.
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