News & Discussion: O-Bahn

[Nort]

Yeah the carparks would have to go......no great loss in such important commercial streets.

And I did mention delivery vehicles......I am not trying to reinvent the wheel.....Rundle Mall has been car free since 1976.

It's a great loss in that if you are entirely removing access to a bunch of locations you will either have to heavily compensate them making the development extremely expensive, or deal with a bunch of expensive and quite justified lawsuits. Likely both.

Rundle Mall is a great example, because to make Rundle Street car free didn't involve removing vehicle access to businesses. They could still be accessed via laneways from North Terrace and Grenfell Street, and AFAIK at the time there weren't any large carparks only accessible from that section of Rundle Street.

For precedent look at the adjacent laneways and streets. The ACC seems like they would love Gawler Place to be pedestrianized off Rundle Mall, but it's a shared space because of the businesses there that require car access. Even James Place, which feels like a narrow pedestrian street is technically a shared space that vehicles can move down because closing it off would cut off the only access to building basement carparks.

I'm all in favour of reducing cars in the city and making things more pedestrian, PT, and cyclist friendly, but I'm also in favour of plans that could realistically be put into action, and removing all private traffic from Grenfell and Currie Streets entirely doesn't seem to pass that test.

[1NEEDS2POST]

There's plenty of capacity in a single bus lane if buses aren't stopping. If you leave a 10 second gap between buses, then you can have 600 buses per hour. One lane each way is 1200 per hour, which is enough for Grenfell-Currie St.

The problem is when buses stop at a stop, hold up traffic for 30 seconds and then start again. Roughly, that limits you to 120 buses per hour. This is a well known problem with BRT and it's why if you look at pictures of BRT in other countries, there are usually four lanes at busy bus stops.

I've posted this picture before of Curitiba, I think it captures a solution to what has been discussed. This road is about the same width as Grenfell-Currie St (maybe a bit wider, but it should fit). There's one lane on the side for all vehicles and a median busway. Cars can still drive along the street, but they can't turn left (or right in Adelaide). The busway has offset bus stops, so there is enough room for an overtaking lane (that's not marked on the road in the photo) at each stop.

[Norman]

This is peak hour on Currie Street



That this doesn't even include those buses coming from the west.

Any bus lane corridor must be 2 lanes minimum in each direction, as the buses will simply clog up at all the bus stops, even if there is a buffer around them.

[bits]

2 lanes plus stops each way? Eg 6 lane wide road?
Currie/Grenfell is 1 lane for stops (and left turns), 1 lane through (for buses) and 1 car lane in each direction. Eg there is 4 lanes dedicated to buses on Grenfell/Currie right now.

[rubberman]

This is peak hour on Currie Street



That this doesn't even include those buses coming from the west.

Any bus lane corridor must be 2 lanes minimum in each direction, as the buses will simply clog up at all the bus stops, even if there is a buffer around them.

We really cannot know how many lanes are required until we optimise what we have. There's plenty of cities which move far more people than Adelaide by PT without needing two lanes each way to achieve it.

Now, obviously, if bus operation in Grenfell is optimised and there's still a problem, then more lanes is on the cards. However, we are nowheee near that point yet.

The issue is that expanding bus lanes to two each way means effectively banning cars. I cannot see any government doing that unless all other options are thoroughly exhausted.

So, if someone thinks two bus only lanes is the answer, then for it to happen, the next step is optimisation of the existing operation. Without doing that, no government is going to jump to banning cars in Grenfell. Heck, the Seat of Adelaide is so marginal that the East End residents losing car access would change the electorate. The government dropped its previous Public Transport proposals because of a few objections. Is it realistic to think that they'd ban cars in Grenfell/Currie to put in an extra bus lane without exhausting all other options?

[1NEEDS2POST]

We really cannot know how many lanes are required until we optimise what we have. There's plenty of cities which move far more people than Adelaide by PT without needing two lanes each way to achieve it.

Now, obviously, if bus operation in Grenfell is optimised and there's still a problem, then more lanes is on the cards. However, we are nowheee near that point yet.

The issue is that expanding bus lanes to two each way means effectively banning cars. I cannot see any government doing that unless all other options are thoroughly exhausted.

So, if someone thinks two bus only lanes is the answer, then for it to happen, the next step is optimisation of the existing operation. Without doing that, no government is going to jump to banning cars in Grenfell. Heck, the Seat of Adelaide is so marginal that the East End residents losing car access would change the electorate. The government dropped its previous Public Transport proposals because of a few objections. Is it realistic to think that they'd ban cars in Grenfell/Currie to put in an extra bus lane without exhausting all other options?

Banning cars is off the table. The choke point is the traffic around bus stops. If you don't have an overtaking lane for buses at stops, then it severely limits how many buses per hour can go through there, so there will need to be two lanes in a direction at some points.

As bits pointed out, there are effectively four lanes for buses now. The difference with my proposal is to move those lanes towards the median and ban right hand turns. The current arrangement has lots of cars turning left and right across the bus lanes. If bus lanes were in the middle of the road with no right hand turns for cars, then there is no reason for cars to cross the bus lanes and slow down buses.

What makes it difficult is we'd need to put the bus stops in the road because the left lane will be for other traffic. So at the stops, instead of taking up four lanes, it would effectively take up six lanes (or five lanes if we offset the stops like in my picture).

Car drivers might whinge because it will involve banning right hand turns and removing car spaces. It's not as controversial as banning cars, but I wouldn't be surprised if there is a huge whinge. Hardly anyone can park on those streets and it takes up heaps of room that could be used for a transit mall.

A few options:

• With offset stops, make the opposite direction one lane, like in my picture. I think it's possible, but it's not the ideal solution.
• Eliminate bike lanes and narrow the foothpaths a bit. I think this is realistic because the footpaths are wide on this street.
• Make the transit mall one way and build another transit mall in the opposite direction on another street. For example, westbound on Currie/Grenfell and eastbound on North Terrace.

[rubberman]

We really cannot know how many lanes are required until we optimise what we have. There's plenty of cities which move far more people than Adelaide by PT without needing two lanes each way to achieve it.

Now, obviously, if bus operation in Grenfell is optimised and there's still a problem, then more lanes is on the cards. However, we are nowheee near that point yet.

The issue is that expanding bus lanes to two each way means effectively banning cars. I cannot see any government doing that unless all other options are thoroughly exhausted.

So, if someone thinks two bus only lanes is the answer, then for it to happen, the next step is optimisation of the existing operation. Without doing that, no government is going to jump to banning cars in Grenfell. Heck, the Seat of Adelaide is so marginal that the East End residents losing car access would change the electorate. The government dropped its previous Public Transport proposals because of a few objections. Is it realistic to think that they'd ban cars in Grenfell/Currie to put in an extra bus lane without exhausting all other options?

Banning cars is off the table. The choke point is the traffic around bus stops. If you don't have an overtaking lane for buses at stops, then it severely limits how many buses per hour can go through there, so there will need to be two lanes in a direction at some points.

As bits pointed out, there are effectively four lanes for buses now. The difference with my proposal is to move those lanes towards the median and ban right hand turns. The current arrangement has lots of cars turning left and right across the bus lanes. If bus lanes were in the middle of the road with no right hand turns for cars, then there is no reason for cars to cross the bus lanes and slow down buses.

What makes it difficult is we'd need to put the bus stops in the road because the left lane will be for other traffic. So at the stops, instead of taking up four lanes, it would effectively take up six lanes (or five lanes if we offset the stops like in my picture).

Car drivers might whinge because it will involve banning right hand turns and removing car spaces. It's not as controversial as banning cars, but I wouldn't be surprised if there is a huge whinge. Hardly anyone can park on those streets and it takes up heaps of room that could be used for a transit mall.

A few options:

• With offset stops, make the opposite direction one lane, like in my picture. I think it's possible, but it's not the ideal solution.
• Eliminate bike lanes and narrow the foothpaths a bit. I think this is realistic because the footpaths are wide on this street.
• Make the transit mall one way and build another transit mall in the opposite direction on another street. For example, westbound on Currie/Grenfell and eastbound on North Terrace.

I agree with most of that, but if you have all door loading and minimum 3 doors per bus, the time at stops drops to less than a half...and only half the number of stops is required. Maybe fewer. In that case, no car spaces need be removed at all, plus buses are pulling in and out from fewer places and not cutting each other off as they do. Plus, it might, repeat might, not be necessary to eliminate the right turns. (Although I am in favour of that in any case, right now).

[RetroGamer87]

There's plenty of capacity in a single bus lane if buses aren't stopping. If you leave a 10 second gap between buses, then you can have 600 buses per hour. One lane each way is 1200 per hour, which is enough for Grenfell-Currie St.

You mean 360 per hour.

I've posted this picture before of Curitiba, I think it captures a solution to what has been discussed. This road is about the same width as Grenfell-Currie St (maybe a bit wider, but it should fit). There's one lane on the side for all vehicles and a median busway. Cars can still drive along the street, but they can't turn left (or right in Adelaide). The busway has offset bus stops, so there is enough room for an overtaking lane (that's not marked on the road in the photo) at each stop.

Gosh, that street looks a lot wider than Currie Street.

[ChillyPhilly]

It's pretty simple - cars should be phased out from Currie-Grenfell Streets. (In a dream world, much of the CBD should be pedestrianised.)

Eventually, only public transport, emergency and utility vehicles and disability access should be permitted.

The Curitiba model won't work because the street is too narrow and not ideal for 'rapid' transit.

[RetroGamer87]

It has been closed between Klemzig Interchange and Paradise Interchange since Monday mornings incident. The damage to the bus is quite extensive.
Repairs are currently being carried out to the track.

It's been nearly a year and that section is still closed?

[crawf]

It has been closed between Klemzig Interchange and Paradise Interchange since Monday mornings incident. The damage to the bus is quite extensive.
Repairs are currently being carried out to the track.

It's been nearly a year and that section is still closed?

Errrr?. It was closed for roughly 1 week.

[Modbury_Man]

It has been closed between Klemzig Interchange and Paradise Interchange since Monday mornings incident. The damage to the bus is quite extensive.
Repairs are currently being carried out to the track.

It's been nearly a year and that section is still closed?

Errrr?. It was closed for roughly 1 week.

Interestingly it seems Google Maps still shows it as closed and the route map when you search for a trip shows the bus going via the road between Paradise and Klemzig

[RetroGamer87]

It's been nearly a year and that section is still closed?

Errrr?. It was closed for roughly 1 week.

Interestingly it seems Google Maps still shows it as closed and the route map when you search for a trip shows the bus going via the road between Paradise and Klemzig

Not just Google Maps. I was on it personally a few weeks ago and they bypassed the damaged section by going through Lower North East Road.

[VLtom]

The O-Bahn is closed every now and again for maintenance, I've caught it several times in the past week and it is operating as normal at normal route speeds

[PD2/20]

Errrr?. It was closed for roughly 1 week.

Interestingly it seems Google Maps still shows it as closed and the route map when you search for a trip shows the bus going via the road between Paradise and Klemzig

Not just Google Maps. I was on it personally a few weeks ago and they bypassed the damaged section by going through Lower North East Road.

Last time I travelled on O-Bahn in April it was definitely open in both directions between Klemzig and Paradise. There is no indication of any diversion on the Adelaide Metro website.

However from time to time there are weekend closures for maintenance that require diversions from the O-Bahn. I recall seeing a notice of such a closure a few weeks ago.

In Google Maps typing in a journey from Klemzig Interchange to Paradise Interchange displays bus service times of 3 minutes between stops. On the accompanying map it does show a route via Lwr NE Rd which is labelled with a car icon, distance 5.5km, time 11 mins. However there is also a label at Paradise which has a bus icon and an journey time of 3 mins.