In the days before systems existed for publishing such schedules and emergency alerts, should public transit service not have been attempted at all?
> Trains by definition need to share the same tracks with catastrophic consequences for getting it wrong.
Just because it uses the same rail gauge as intercity freight doesn't require it to run on the same set of tracks. But if it did, I assume "local-first" entails other traffic just being excluded when an emergency in the local system necessitates it.
Wikipedia has a good survey [0].
Of course, centralized signaling is better, allowing for greater efficiency, helps dispatch keep track better track of the trains, makes handling malfunctioning signals a lot safer, among many other benefits. But it doesn't mean local signaling can't be done.
I don’t know, but I would imagine, there’s still a block based setup as a failsafe backup in most or all modern rail systems.
https://www.nytimes.com/interactive/2025/04/20/nyregion/nyc-...
For me, this was the best picture:
https://static01.nytimes.com/newsgraphics/2025-03-10-subway-...
Someone has to stand at that machine 24 hours a day and push and pull levers to keep the trains from whacking one another.
The US congressional committee that recommended construction of the railroad was called the "Select Committee on the Pacific Railroad and Telegraph".
So it seems very early it was decided that no, rail transit systems should not be built without communications/publishing infrastructure.
[0] https://en.wikipedia.org/wiki/First_transcontinental_railroa...
> Just because it uses the same rail gauge as intercity freight doesn't require it to run on the same set of tracks
Building a replica set of tracks that runs parallel to the current tracks just to avoid sharing doesn't strike me as a good use of anyone's time/money.
> "local-first" entails other traffic just being excluded
And how are you going to notify them that they are excluded when the network is down?
Edit, for the pedantic: There's a huge difference between horizontal complexity (i.e. variety of transit options) and vertical complexity (complexity of a particular option). We have less horizontal complexity than we used to; but vertical complexity of a modern railroad is obscene compared to historical standards.
> But if it did, I assume "local-first" entails other traffic just being excluded when an emergency in the local system necessitates it.
No dice; as consider just 14 hours ago:
https://x.com/SFBARTalert/status/1963772853947355630?ref_src...
How does a local-first train safely operate if it could go through a police zone? You need communication, by definition, not local-first.
I think our over reliance on the telecom network has lead to safety issues- mostly in terms of "what to do when the telecom goes down." Because on the whole, its astoundingly reliable.
We're talking about BART, which uses a track gauge of 5'6" instead of the standard US rail gauge of 4'8.5". They can't run on the same tracks.
(Actually, this is generally true even for those systems that do use 4'8.5" gauge track--I suspect that the standard US freight car envelope doesn't actually fit on most subway systems.)
That said there are other reasons a subway could end up being subject to Federal Railroad Administration[2] rules. I will note that I'm not an expert on those rules. But, generally passenger rail systems in the US are subject to Positive Train Control[3] or equivalent. It appears BART is actually one of the earliest adopters of Automatic Train Control[4], which appears to be a PTC equivalent. If not more automated.
[1] https://en.wikipedia.org/wiki/Loading_gauge
[2] https://en.wikipedia.org/wiki/Federal_Railroad_Administratio...
[3] https://en.wikipedia.org/wiki/Positive_train_control
[4] https://en.wikipedia.org/wiki/Bay_Area_Rapid_Transit#Automat...
As a related aside, the Chicago Transit Authority still ran freight on its tracks until not that long ago. Maybe the early 2000's?
It is certainly possible to send a freight train that will fit in most subway tunnels of the right gauge, but you may need a short locomotive and short cars.
(After all, what are the maintenance trains but a form of freight?)
Eh? I thought we (TTC, in Toronto) were the only ones making that mistake.
BART has a non-standard rail gauge size that precludes it from interoperability with other rail networks.
Other ones I'm aware of are Washington DC's metro, and Toronto's subway and streetcars.
