News & Discussion: Roads & Traffic

[SBD]

Since the freeway is grade separated, we may as well make it an O-Bahn track. This idea has been discussed before: https://www.sensational-adelaide.com/fo ... =17&t=6340

It's actually a really good idea. According to one source (which I can't verify, but sounds plausible), O-Bahn track is rated to 165 km/h. This would be a huge improvement on the current bus route and O-Bahn track is cheap. Electric buses can use very powerful motors, so if diesel buses cannot go that fast, electric buses can.

The current O-Bahn is over 30 years old and the ride quality shows it; as a result speed has been reduced from 100km/h to 80km/h. Buses also need to be specially modified with guide wheels to run on the tracks and the width of modern buses has been an issue in the past with tyre walls scraping on the concrete tracks causing faster-than-normal wear. You also can't simply resurface the O-Bahn like you do a normal road when it needs repairing.

It's definitely been successful, is popular with commuters, massively cuts travel time and has its advantages over rail, but if it's that unbelievably wonderful why did we stop at building only one?

Honestly, I think when the time comes to renew the O-Bahn they'll replace it with a more conventional unguided busway. The deep piles are already in the ground I presume it would be a case of removing the concrete sleepers and tracks and replacing them with a flat deck to lay pavement onto. A conventional busway would be more compatible with our bus fleet, not require special modifications to buses, and be easier to maintain and repair.

Funnily enough, this is the perfect use for so-called trackless trams which are really just guided buses. Put the guide strips in the middle, and let the computers do the job of steering instead of those little wheels.

The O-Bahn is over 40 years old. It's not unreasonable to expect a major renovation program.

I'd also ask if it's ok for buses to do 100kph on reserved track, why doesn't the State Government target trams and trains with similar speeds?

I imagine the modifications to create a "trackless tram" from a normal bus are at least as significant as to make an O-bahn bus. The O'bahn corridor would not be suitable for a "conventional busway" as the track would not be wide enough without some kind of automatic guide.

Fair question about trains and trams. I suspect it has to do with the frequency of level crossings. I wonder what the longest segments are in Adelaide without any level crossings (vehicle or pedestrian).

[rubberman]

The current O-Bahn is over 30 years old and the ride quality shows it; as a result speed has been reduced from 100km/h to 80km/h. Buses also need to be specially modified with guide wheels to run on the tracks and the width of modern buses has been an issue in the past with tyre walls scraping on the concrete tracks causing faster-than-normal wear. You also can't simply resurface the O-Bahn like you do a normal road when it needs repairing.

It's definitely been successful, is popular with commuters, massively cuts travel time and has its advantages over rail, but if it's that unbelievably wonderful why did we stop at building only one?

Honestly, I think when the time comes to renew the O-Bahn they'll replace it with a more conventional unguided busway. The deep piles are already in the ground I presume it would be a case of removing the concrete sleepers and tracks and replacing them with a flat deck to lay pavement onto. A conventional busway would be more compatible with our bus fleet, not require special modifications to buses, and be easier to maintain and repair.

Funnily enough, this is the perfect use for so-called trackless trams which are really just guided buses. Put the guide strips in the middle, and let the computers do the job of steering instead of those little wheels.

The O-Bahn is over 40 years old. It's not unreasonable to expect a major renovation program.

I'd also ask if it's ok for buses to do 100kph on reserved track, why doesn't the State Government target trams and trains with similar speeds?

I imagine the modifications to create a "trackless tram" from a normal bus are at least as significant as to make an O-bahn bus. The O'bahn corridor would not be suitable for a "conventional busway" as the track would not be wide enough without some kind of automatic guide.

Fair question about trains and trams. I suspect it has to do with the frequency of level crossings. I wonder what the longest segments are in Adelaide without any level crossings (vehicle or pedestrian).

Trackless trams actually have that automatic guide. It's just not a mechanical one.

[SBD]

Funnily enough, this is the perfect use for so-called trackless trams which are really just guided buses. Put the guide strips in the middle, and let the computers do the job of steering instead of those little wheels.

The O-Bahn is over 40 years old. It's not unreasonable to expect a major renovation program.

I'd also ask if it's ok for buses to do 100kph on reserved track, why doesn't the State Government target trams and trains with similar speeds?

I imagine the modifications to create a "trackless tram" from a normal bus are at least as significant as to make an O-bahn bus. The O'bahn corridor would not be suitable for a "conventional busway" as the track would not be wide enough without some kind of automatic guide.

Fair question about trains and trams. I suspect it has to do with the frequency of level crossings. I wonder what the longest segments are in Adelaide without any level crossings (vehicle or pedestrian).

Trackless trams actually have that automatic guide. It's just not a mechanical one.

I understood that. That part of my answer was to @Spotto's comment that O-Bahn buses need to be specially modified to operate on the track. I think a trackless tram modification would be at least as expensive as a guidewheel modification.

The other part is the suggestion of a "conventional unguided busway" - I suspect that the track/corridor is not wide enough to support high speed operations in opposing directions without a lot more walls (outside and in the middle) and space to manually avoid scraping them.

[Joelmark]

I suspect that in 10 or 15 year’s time the concrete busway will simply be replaced by exactly the same concrete busway, once they get maximum use out of the current structure- 50 years isn’t too bad.
Much less likely would be Option B - replacing it with a Light Rail line as was originally planned, right up until tender in 1980. The corridor I believe (others may know better) had been designed to be compatible with trams, as in wide enough and overhead clearances high enough along the Torrens. It wouldn’t be too difficult to integrate the Rymill Park tunnel into the North Terrace tram extension. Rundle Road also has a tram corridor reservation (this is assuming the long vaunted Grenfell-Currie transport mall remains that; long vaunted).
I’m unashamedly pro-tram but I can’t see how a light rail line would be quicker than the current set-up in terms of Grenfell Street to Modbury.

[Patrick_27]

I suspect that in 10 or 15 year’s time the concrete busway will simply be replaced by exactly the same concrete busway, once they get maximum use out of the current structure- 50 years isn’t too bad.
Much less likely would be Option B - replacing it with a Light Rail line as was originally planned, right up until tender in 1980. The corridor I believe (others may know better) had been designed to be compatible with trams, as in wide enough and overhead clearances high enough along the Torrens. It wouldn’t be too difficult to integrate the Rymill Park tunnel into the North Terrace tram extension. Rundle Road also has a tram corridor reservation (this is assuming the long vaunted Grenfell-Currie transport mall remains that; long vaunted).
I’m unashamedly pro-tram but I can’t see how a light rail line would be quicker than the current set-up in terms of Grenfell Street to Modbury.

I hope that when the time comes in 10-15 years time to replace the O'Bahn that the powers that be might reconsider a Modbury freeway as an option, peak hour traffic along north-east and lower north-east road(s) could already justify a third aerial heading north-east and I can only see this becoming more of a issue. Two lanes private vehicle lanes in each direction plus a dedicated bus lane, would solve all these problems.

[ChillyPhilly]

Modbury Freeway similar to MATS would be a massive environmental disaster. At best, significant improvements to NE Road should be considered - a permanent express bus lane, accessible footbridges over the road and grade separations at key intersections would be sufficient. Unfortunately due to the nature of the northeast suburbs being a cul-de-sac ridden hell, car dependency will remain high.

I don't think we'll see the O-Bahn service replaced in our lifetimes. Light rail isn't really suitable for the urban form along the corridor, bar maybe an extra stop at Lochiel Park to boost its sustainability.

I do believe we need buses able to use the access ramps at Grand Junction Road.

[bits]

Unfortunately due to the nature of the northeast suburbs being a cul-de-sac ridden hell, car dependency will remain high.

North East suburbs has highest public transport use.

[ChillyPhilly]

Property acquisitions in major intersection upgrade

The Transport Department is embarking on a $35 million upgrade of the intersection of Glen Osmond and Fullarton roads, with a spokesperson telling InDaily two commercial properties are expected to be fully acquired, while up to another 18 will have “partial acquisitions”.

from indaily, see article: https://indaily.com.au/news/local/2021/ ... n-upgrade/

What's with these projects adding a pointless third lane?

I guess it adds 50% to the number of vehicles that get through the intersection in the same length green-light cycle.

It would be good if enough drivers knew how to safely and efficiently zip merge, but this is not in the majority of Adelaide's driving culture.

Unfortunately due to the nature of the northeast suburbs being a cul-de-sac ridden hell, car dependency will remain high.

North East suburbs has highest public transport use.

The O-Bahn is the most heavily patronised public transport service in Adelaide, yes.

[bits]

The O-Bahn is the most heavily patronised public transport service in Adelaide, yes.

As it stands it appears the north east actually has the lowest car dependency, most there use public transport or bikeways.

With more parks, schools, malls and supermarkets than other areas NE residents are likely within walking distance to those also.

Cul-de-sac layout allows children to more safely ride bikes with more off-road paths, reduced car speeds and no through traffic. Children can also play ball sports directly in front of their home instead of needing to be driven to a park. It also encourages walking to local destinations as taking a car may require taking a much longer path to reach your destination.

So which outter suburbs should the North East be more like? Sheidow Park, Aberfoyle Park, Hallet Cove, Bellevue Heights, North Haven?

[Nort]

It also encourages walking to local destinations as taking a car may require taking a much longer path to reach your destination.

Not with more modern cul-de-sacs it doesn't. Historically there were more alleyways that allowed cutting through, but due to security concerns many have closed over years and new developments rarely include them, meaning the walking routes are basically the same as driving routes.

[bits]

Not with more modern cul-de-sacs it doesn't. Historically there were more alleyways that allowed cutting through, but due to security concerns many have closed over years and new developments rarely include them, meaning the walking routes are basically the same as driving routes.

If we pick on the far north east at the very edge of Adelaide which is heavily cul-de-sacs there is through paths almost always.

[HeapsGood]

Magill and Portrush being upgraded at a cost of 98 million for a few extra lanes, property acquisitions NO over or under passes ????? what the hell...

[Nort]

Magill and Portrush being upgraded at a cost of 98 million for a few extra lanes, property acquisitions NO over or under passes ????? what the hell...

Demolishing a few dozen properties and upgrading a busy intersection without being able to close it down is expensive.

[cmet]

Magill and Portrush being upgraded at a cost of 98 million for a few extra lanes, property acquisitions NO over or under passes ????? what the hell...

Always laugh when people complain about the prices of these projects, like how would you even know what a certain infrastructure project should cost..?

[HeapsGood]

I always laugh when other people always laugh. It's like a laughter contagion.