News & Discussion: O-Bahn

[SouthAussie94]

One of the reasons for the success of the O-Bahn is that it is allowed to operate at much higher speeds than competing modes.

Thus, trams dodder down to Glenelg in their own right of way, but buses on the O-Bahn are allowed much higher speeds.

Makes rigorous comparison impossible.

To be fair, the Glenelg tram as more stops, with a much smaller distance between stops compared to the O-Bahn.

The O-Bahn also has certainty about which stops will be serviced, whereas the tram drive doesn't know whether the stop will be serviced until someone either hails the tram, or pushes the button onboard

Both of these would effect service speed.

Saying that, I don't catch the tram, nor do I have enough knowledge to make comparisons with tram systems elsewhere.

[claybro]

The tram could travel MUCH faster and the journey time is not just to do with the amount of stops. There is a whole discussion on the tram thread re this. Same with suburban trains. Somewhere along the way, Adelaide went from a very efficient and quick train and tram system, to somewhat of a joke. Oddly enough, when presented with untried and new technology in the form of the Obahn, seems Adelaide has excelled. We can do buses like no one else, but throw in some steel rails, and it seems everyone goes into a blind panic, so in Adelaide terms, comparison with Obahn and all types of rail are not really relevant.

[monotonehell]

Originally the guide rails were only going to be installed on the "curvy" bit between Klemzig and Hackney in order to allow faster speeds. The rest of the busway out to TTP was intended to be a normal road. The public made a lot of noise and demanded the guides be installed along the entire project, due to safety and speed concerns.

Thanks for the info, I was not aware of the option to only partially track the corridor but it does make sense to have done it properly, albeit for political browny points. Although not a fan of the busway, I do get that the "to door" service in the outer suburbs is better with the busway than fixed rail, but I'm not sure that pointing to the ongoing success of the busway proves it is better than heavy rail is correct. Would heavy rail with feeder bus services be more appealing for example if the CBD had an underground loop so that commuters were delivered more centrally, or SA could actually run a train system properly and at design speed?- It would certainly prove higher capacity and speed if run properly. I suspect this would be light years away, so maybe the idea of a PT/ pedestrian only zone for Grenfell/ Currie streets, with decent substantial shelters is the way to go for the next 30odd years, if the Obahn track can be maintained for that long.

Sorry if I was unclear. I was comparing light rail to O-Bahn. And then saying that once O-Bahn reaches the peak of its pax capacity, the next step is to switch to heavy rail as light rail's peak capacity is not much more than O-Bahn's.

You bring up some interesting points.
What if:
* There were train stops throughout the CBD.
* The trains were ran at speed.

These can be added to a whole laundry list of attributes often attributed to rail. For example:
* Known and easy to understand route.
* Clean stations with services and amenities. (Note that a lot of Adelaide's suburban train stations are often referred to as little more than a "bus shelter".)

I wish I could remember the paper's name or the author, which I've posted on these forums before. But the gist of it is that a lot of positive features that people attribute to rail, have very little to do with that transport mode, and are actually bolt-on features which can and have been applied to BRT in various places.

Add to this the fact that pax hate transferring, as it adds time to a journey. Especially where service frequency means added waiting time. As soon as you add more than ten minutes to a journey, a lot of people will prefer to take their car. A peak period service which collects people near their home, and which is a single vehicle journey to their destination, is very attractive. On relatively short journeys, like the N.E. Suburbs, having to take a feeder service and transfer is less attractive. It makes sense on further out, more linear services, like the Southern or Gawler Lines.

[PeFe]

What percentage of O-Bahn trips are one bus journeys?
I tried to find out using the Adelaide Metro timetables, but it was near impossible to work out.....
Does anyone know?

I believe the number of one seat journeys is highest during the day, but at weekends/night time a considerable number of trips involve transfers, so the belief that the O-Bahn is a non-transfer service is not true.

The weakness of the O-Bahn is the capacity issues (60 people on 1 bus, compared to 160-250 people on 1 tram)
Also the number of buses that clog up major thoroughfares like Grenfell/Currie Streets, its an issue and it will only get worse.

The new Sydney CBD/South East Light rail will be tram/bus transfer, the future issue there is capacity (should it be a metro?)
Also the Gold Coast light rail is tram/bus transfer.....a big success, why would Adelaide be any different?

The O-Bahn has not been replicated in any great number around the world (bar the few exceptions mentioned) so you have got to ask yourself why?
Capacity would be my guess, if you have a transit corridor like the linear park, then light rail/metro would be the world's answer for that particular space. BRT seems to be usually built on main roads, creating a "bus only" lane.

Having said all this I am actually looking forward to the new O-Bahn tunnel opening at the end of the year. I believe it will be a winner, muck quicker transit times into the CBD, another "plus" for the public transport in the eyes of "Joe public".

One further suggestion though, maybe during the weekday business hours, the buses should all be the longer/articulated kind, so this addresses the capacity and number of buses in Grenfell St issue. This of course may entail more transfers down the line though....

[adelaide transport]

The current scheduling of buses during the weekday interpeak is a mixture of rigids and articulated buses ,and adequately handles the loads. Sometimes there are Artics with light loads, but that is deliberate as more than likely that Artic will be used on either a commuter or a school run with heavy loadings, where that Artic is needed.
Also at some stage during the day many runs(Artic and Rigids) operate Non-O-Bahn services(ie 300 Suburban Collector route).
With all door loading commencing later in the year this could create an interesting scenario.
Also there are some peak and off peak services that that use non-O-Bahn vehicles-this could cause confusion when these buses are used and only load at the front door.?

[monotonehell]

These same misunderstandings come up every few years...

What percentage of O-Bahn trips are one bus journeys? I believe the number of one seat journeys is highest during the day, but at weekends/night time a considerable number of trips involve transfers, so the belief that the O-Bahn is a non-transfer service is not true.

You're not asking a valid question in relation to the point I made above. You've set up a strawman argument. The one seat journeys are mostly happening in peak period. Outside of peak, where the demand for seats is lower, lower patronised services connect to main line services. This adaptability is an advantage over rail where poorly patronised services carry a similar cost to a full train. Where feeder services must be run at all times, so no door to door services can be run.

The weakness of the O-Bahn is the capacity issues (60 people on 1 bus, compared to 160-250 people on 1 tram)

Again. Not a weakness. Your argument assumes that max capacity is required all day. It also ignores the fact that vehicles can run on the O-Bahn with a few seconds separation, compared to trains which require minutes separation. The actual peak capacity of the O-Bahn is near the peak capacity of light rail. This also ignores that those separate vehicles can then run on-street to and from different locations (door to door).

So there's two situations to be compared here - on and off peak. Your arguments compound both situations and attempt to argue from both directions. That's a logical fallacy.

Also the number of buses that clog up major thoroughfares like Grenfell/Currie Streets, its an issue and it will only get worse.

This is true. But it's an implementation issue, not a O-Bahn issue. One could argue that rail gets congested because on one track there's no way for trains to pass ones waiting at a station, or that they have to wait for one train to leave the station for another to visit.

The new Sydney CBD/South East Light rail will be tram/bus transfer, the future issue there is capacity (should it be a metro?)
Also the Gold Coast light rail is tram/bus transfer.....a big success, why would Adelaide be any different?

I know very little about these two examples so I can't comment much more than saying different situations better suit different modes and implementations. There's no one mode that's better in ALL situations. The O-Bahn has and does suit the N.E. Suburbs' situation very well. In hindsight it was the correct decision.

The O-Bahn has not been replicated in any great number around the world (bar the few exceptions mentioned) so you have got to ask yourself why?
Capacity would be my guess, if you have a transit corridor like the linear park, then light rail/metro would be the world's answer for that particular space. BRT seems to be usually built on main roads, creating a "bus only" lane.

I wish I could find that damn paper - it had a graph showing capacity versus speed of various modes. The O-Bahn was on top of everything until heavy rail. The graph and the paper showed that when your capacity requirements exceed that of the O-Bahn, light rail is no longer an option.

Having said all this I am actually looking forward to the new O-Bahn tunnel opening at the end of the year. I believe it will be a winner, muck quicker transit times into the CBD, another "plus" for the public transport in the eyes of "Joe public".

One further suggestion though, maybe during the weekday business hours, the buses should all be the longer/articulated kind, so this addresses the capacity and number of buses in Grenfell St issue. This of course may entail more transfers down the line though....

I'm looking forward to it being opened. But I'm worried that (as you mention) there will be major congestion during peak at the Grenfell Street end. They need to work out some kind of "exchange like" solutions, to deal with all the buses. Perhaps they already have and I worry for nothing.

I thought that was how it was run now. But some people have told me that even though the time tables require artics at certain times, real life gets in the way and on-ground situations mean that occasionally a lower capacity bus is sent out on a route.

[Westside]

The new Sydney CBD/South East Light rail will be tram/bus transfer, the future issue there is capacity (should it be a metro?)
Also the Gold Coast light rail is tram/bus transfer.....a big success, why would Adelaide be any different?

I know very little about these two examples so I can't comment much more than saying different situations better suit different modes and implementations. There's no one mode that's better in ALL situations. The O-Bahn has and does suit the N.E. Suburbs' situation very well. In hindsight it was the correct decision.

OK, so first of all, both of these initiatives have very little in comparison to the NE Suburbs corridor. They were both designed on a traditional light rail "string of pearls" route (perhaps it's been mentioned on here before). The idea being that the light rail has a number of stops along the way that all generate passengers and are destinations in their own right. This way you get passengers disembarking and alighting along the whole corridor with the bulk of passengers only completing a small portion of the overall journey. You'll find in both GC and Sydney peak hour traffic on their LRs will be very similar in each direction. This is a very different situation in the NE corridor, which is basically a funnel of passengers from outer suburbs converging to all head into the city. Consider the the minimal traffic heading out to TTP in the morning compared to the traffic heading in.

In GC, there are bus hubs at both ends to allow for transfers, but their aim is not to feed passengers from one mode to the other (akin to the odd passenger taking a 26x and transferring to the Glenelg tram. It happens, but it's not its primary focus). In Sydney, yes, a number of competing bus routes that used to travel to the city will now terminate at the ends, but this will be used mainly during off peak, with peak express buses still required to run to the city to funnel people in. (And not to mention SE Sydney residents are already up in arms about having to transfer!).

So while light rail may have been a good decision in these examples, it does not equate to it being a good decision for the NE corridor. Consider the PT patronage in the outer suburbs where a 5xx bus is present, over the PT patronage in a 4xx suburb where a transfer to rail is required and you can definitely see the o-bahn as a complete success. (Now, if we had an underground city loop, that may change, but that wasn't foreseeable when the o-bahn was constructed, and it still isn't foreseeable now ).

[PeFe]

The capacity issue (number of vehicles used,road congestion etc) wont go away in the future. The limits of the O-Bahn will still be there in the future......people will always be asking "should it light rail?"
Imagine a light rail service where daytime frequencies are every 5 minutes and off-peak 10 minutes. No need for commuters to look at a timetable..ever, yes there is a downside, you have to transfer to a bus at Paradise or Modbury.
The number of trams/trains able to use the corridor per hour........if this is the same as heavy rail, then 1 per minute (just like the Paris Metro at peak hour) but I don't think Adelaide patronage could ever justify this.
I did a little research on the capacity issue comparing Adelaide to Los Angeles.

Adelaide O-Bahn daily boardings : 31,000
https://en.wikipedia.org/wiki/O-Bahn_Busway

Los Angeles Blue Line Light Rail : 86,000
https://en.wikipedia.org/wiki/Blue_Line ... les_Metro)
Los Angeles Expo Light Rail : 55,000
https://en.wikipedia.org/wiki/Expo_Line ... les_Metro)

And for those of you who are interested here are my thoughts on the Los Angeles and Portland light rail systems after I travelled to the USA in 2013.
viewtopic.php?f=18&t=4804

[claybro]

One thing not taken into consideration in the comparison is the use of diesel/gas buses in comparison to a light rail. Electric vehicles accelerate much faster, and are quieter/less polluting. I don't believe capacity issues will be a problem in the foreseeable future, but if we are to stick with Obahn going forward there are some critical things that need to be considered.
1.Ever increasing amounts of diesel buses in Grenfell Street will not be good from a congestion /pollution view, even now the roar as these buses take of in a plume of diesel smoke does not create a nice environment in Grenfell or KWS for that matter.
2. Something needs to be done re the wobble and bounce at the rear of articulated buses-(light rail provides a much smoother ride). This will get worse as the track deteriorates.

So going forward with the Obahn will require some major dollars anyway ie electric buses,(which reduces their flexibility at the outer end) and consider undergrounding the buses in Grenfell Street, similar to what has been done in Wellington Street busport here in Perth.

[rubberman]

One thing not taken into consideration in the comparison is the use of diesel/gas buses in comparison to a light rail. Electric vehicles accelerate much faster, and are quieter/less polluting. I don't believe capacity issues will be a problem in the foreseeable future, but if we are to stick with Obahn going forward there are some critical things that need to be considered.
1.Ever increasing amounts of diesel buses in Grenfell Street will not be good from a congestion /pollution view, even now the roar as these buses take of in a plume of diesel smoke does not create a nice environment in Grenfell or KWS for that matter.
2. Something needs to be done re the wobble and bounce at the rear of articulated buses-(light rail provides a much smoother ride). This will get worse as the track deteriorates.

So going forward with the Obahn will require some major dollars anyway ie electric buses,(which reduces their flexibility at the outer end) and consider undergrounding the buses in Grenfell Street, similar to what has been done in Wellington Street busport here in Perth.

Trolleybuses then?

[bits]

Also there are some peak and off peak services that that use non-O-Bahn vehicles-this could cause confusion when these buses are used and only load at the front door.?

How are non o-bahn buses running on the o-bahn?

[bits]

Imagine a light rail service where daytime frequencies are every 5 minutes and off-peak 10 minutes.

The fixed line of ttp to Hackney has buses already doing that, but much better.
In peak the o-bahn has buses seconds apart, not minutes.

Changing the corridor to have the frequency you want would be a severe downgrade of what is already there.

[adelaide transport]

Also there are some peak and off peak services that that use non-O-Bahn vehicles-this could cause confusion when these buses are used and only load at the front door.?

How are non o-bahn buses running on the o-bahn?

I never said they used the actual busway-there are services operating from Paradise and TTP interchnges that are feeder services, likewise there are M44 peak services that run to and from the City to Marion.

[bits]

The fixed line of ttp to Hackney has buses already doing that, but much better.
In peak the o-bahn has buses seconds apart, not minutes.

Changing the corridor to have the frequency you want would be a severe downgrade of what is already there.

Figured I should show some data for this.
Tomorrow 7:30 for zone b and zone c. There is likely more I have not included.

[monotonehell]

The capacity issue (number of vehicles used,road congestion etc) wont go away in the future. The limits of the O-Bahn will still be there in the future......people will always be asking "should it light rail?"

And again - I draw your attention to the fact that the maximum capacity of the O-Bahn is around the same as light rail, with the added advantage of frequency and one seat journeys in peak.

People will keep asking, for as long as they fail to look at the facts of the matter. Pax capacity is not a reason. Congestion at the end of the line is an implementation problem, not a system problem.

Light rail, BRT and guided BRT are in the same capacity category. They are a choice at the same level, depending on the individual circumstances of the transport corridor.

The next step in capacity is a heavy rail corridor. But that requires a much greater patronage to be worth it.

There are no current compelling reasons to replace the O-Bahn with light rail at all. A change in circumstances might mean that the O-Bahn will need to be replaced. For example, the track is already past the end of its expected life, how much longer will it last?


If people are interested in further reading, Prof Graham Currie is a highly cited contributor to the literature. Here's a good summary of things for a starter - http://scholarcommons.usf.edu/cgi/viewc ... ontext=jpt