[COM] South Road Superway | $842m | 3km

[Amused]

So much speculation... I won't buy a computer mouse without weighing up the cost vs benefits of at least half a dozen different options. Are we actually suggesting that the Government jumped on the $850million option without giving some other options at least a sideward glance? I'm assuming there was some good reasons why the road we'll be looking at in a few years time will be hovering over South Road and not buried under it. I'm also going to assume that cost was one of those factors examined. I know that Government ministers can be fairly stupid or at least make some silly decisions, but I doubt it was the mailroom guy who selected the final package.

[neoballmon]

Ok, I do see where you're coming from Amused, and I guess I'll have to believe that it is the most cost effective option available that provides the necessary function, but just looking at it..it looks so extreme and overpriced. It's just hard to accept..


Also, looking at the July 6 Nearmap photo, at the northern end of this project, I'm noticing the alingment of their supports are much further to the west than the previous road. I knew they were building a larger loop connecting to the Salisbury Highway, but I thought it would use the old bridge, hence re-aligning traffic on there during construction. But now it looks like they'll have to build a brand new bridge and eventually demolish the old one. Can anyone confirm this? And are they building the extra bridges that will be reqired for the Northern Connector? Plans (that I've found at least) have been very scarce, and to be honest, I've been able to make more sense from the Northern Connector proposed, unfinalised images of this interchange!

[[Shuz]]

There seems to be a tendency to view the structure (of a project) as its total capital cost. People often forget that part of the $900 something million dollars to build this also includes hiring machinery and equipment to put it into place, employing hundreds of construction workers, expenses to ensure OHSW safety standards are met during and post-construction, etc.

The actual concrete and physical elements would be much less than $900m. I don't know how much exactly, but I'd estimate $700m at most.

[neoballmon]

There seems to be a tendency to view the structure (of a project) as its total capital cost. People often forget that part of the $900 something million dollars to build this also includes hiring machinery and equipment to put it into place, employing hundreds of construction workers, expenses to ensure OHSW safety standards are met during and post-construction, etc.

The actual concrete and physical elements would be much less than $900m. I don't know how much exactly, but I'd estimate $700m at most.

I do understand all of these expenses are included in their costing, as well as the costs of re-locating traffic, local network upgrades (Gallipoli Road, Davis Street Bridge, Wing Street Bridge) and I wouldn't be suprised if this project does come in slightly under budget, like other projects have in recent times. But the construction of the trusses and the pre-cast yard would have cost them 10's of millions alone. I'm sure the rental of boreing machines would be significantly less, and there wouldn't be as much need for specialised concrete piers and structures with a tunnel, as thick walls (and central wall) would provide the majority of the support.

[claybro]

Surely the cost of tunelling v's elevated road is easy to compare. The Clem7 tunnel in Brisbane cost 2.2 billion for approx 4.5km of tunnel. At cost per /KM it would appear the elevated road works out MUCH cheaper. Elevated roads are not however suitable for higher density residential areas and therefore a tunnel would be the only option further south unless major property aquesition along south road is undertaken, then the cost of tunelling becomes more economic. A 20m high elevated road would cause an outrage through inner western adelaide.

[Aidan]

I do understand all of these expenses are included in their costing, as well as the costs of re-locating traffic, local network upgrades (Gallipoli Road, Davis Street Bridge, Wing Street Bridge) and I wouldn't be suprised if this project does come in slightly under budget, like other projects have in recent times. But the construction of the trusses and the pre-cast yard would have cost them 10's of millions alone. I'm sure the rental of boreing machines would be significantly less, and there wouldn't be as much need for specialised concrete piers and structures with a tunnel, as thick walls (and central wall) would provide the majority of the support.

The tunnel walls themselves are specialized precast concrete structures, and tunnels constructed with tunnel boring machines don't have structural central walls (and don't normally have any central walls).

Suitable TBMs are unlikely to be available for rent, and not very likely to be available used. This is partly due to different geological conditions and tunnel size requirements making suitable ones quite rare, and partly because large TBMs are very difficult to transport.

[Aidan]

Surely the cost of tunelling v's elevated road is easy to compare. The Clem7 tunnel in Brisbane cost 2.2 billion for approx 4.5km of tunnel. At cost per /KM it would appear the elevated road works out MUCH cheaper. Elevated roads are not however suitable for higher density residential areas and therefore a tunnel would be the only option further south unless major property aquesition along south road is undertaken, then the cost of tunelling becomes more economic. A 20m high elevated road would cause an outrage through inner western adelaide.

True, though they're arguably even more unsuitable for low density residential areas than high density ones. But remember an elevated road doesn't actually need to be 20m high. A 20ft high elevated road should be suitable for the non residential stretch between Richmond Road and SDBD.

[Wayno]

i'm a bit confused by this project. Realise it's for improving freight transport times - all good. But why does it start so far south of GJ road? Simply to avoid the Days Rd intersection lights? Surely a different more cost effective approach could have been used for that intersection, and start the superway 500m further north?

Ignore my prev post - i examined nearmap more closely and now understand why the superway starts where it does. Let's take discussion about tunneling etc to another thread and refocus on news & construction.

[claybro]

Suitable TBMs are unlikely to be available for rent, and not very likely to be available used. This is partly due to different geological conditions and tunnel size requirements making suitable ones quite rare, and partly because large TBMs are very difficult to transport.

Also, arent the boring machines generally bored off into a side bore, and then entombed in concrete as they cant be "backed out" of the tunnel they create?

[Aidan]

Suitable TBMs are unlikely to be available for rent, and not very likely to be available used. This is partly due to different geological conditions and tunnel size requirements making suitable ones quite rare, and partly because large TBMs are very difficult to transport.

Also, arent the boring machines generally bored off into a side bore, and then entombed in concrete as they cant be "backed out" of the tunnel they create?

Not generally but sometimes. As I said, large ones are difficult to transport, so burying them is an option especially in inaccessible locations. When the Channel Tunnel was constructed, two of the four TBMs that constructed the running tunnels were buried under the middle of the English Channel, and the other two were dismantled in the tunnels.

But in more accessible locations, getting them out of the ground isn't a big problem because they can come out forwards.


(If you want to continue this discussion, please start a new thread for it)

[rev]

Surely the cost of tunelling v's elevated road is easy to compare. The Clem7 tunnel in Brisbane cost 2.2 billion for approx 4.5km of tunnel. At cost per /KM it would appear the elevated road works out MUCH cheaper. Elevated roads are not however suitable for higher density residential areas and therefore a tunnel would be the only option further south unless major property aquesition along south road is undertaken, then the cost of tunelling becomes more economic. A 20m high elevated road would cause an outrage through inner western adelaide.

Property acquisition has already occurred around Ridleyton/Croydon, to what extent I don't know, but I assume it is continuing along sections of South Road not far from the Superway.
Unless I'm mistaken there is a planning study currently underway for the section between Anzac Hwy and Regency Rd.

[Mr Smith]

From a source within Dept Transport & Infrastructure, the plan for South Rd between Regency Rd and Anzay Hwy is finished and is either with the Govt for consideration, or soon will be. The 'corridor' will be the existing South Rd and for the section between Torrens Rd and Port Rd, most if not all of the properties on the western side of South Rd are owned by Dept Transport. The section between Outer Harbour railway line and south of Grange Road will be dealt with by way of a trench rather than a tunnel as prev planned. I gather there are a couple of options for the section south of Grange Rd to Anzac Hwy, trench v tunnel, although was not able to get anything more specific, other than that this section will definitely NOT be elevated, as most of us probably knew already, as would be political suicide for the State Govt. The road will be a 'non stop' corridor, however speed limits will be relatively low, probably 60 - 80kph, due to the frequency on merging traffic, particularly the section between Henley Beach rd and Anzac Hwy. Probably a comparable road treatment would be South Dowling St in Eastern Sydney.

There has been no detailed planning between Anzac Highway and the Southern Expressway.

[neoballmon]

I'm sorry for taking the conversation so off-topic, I'll try not to let it happen again. I really didn't expect that much discussion from it all though.

Property acquisition has already occurred around Ridleyton/Croydon, to what extent I don't know, but I assume it is continuing along sections of South Road not far from the Superway.
Unless I'm mistaken there is a planning study currently underway for the section between Anzac Hwy and Regency Rd.

I believe you're right Rev, given the high number of vacant lots between Port Road and Hawker Street along the western side of South Road. I'd also have to asume the majority of the little shops by Hawker that seem abandonned have also been bought out by the government once tennants decided to vacate. One would hope that they buy every lot along the stretch and not allow new owners to purchase, as this land will be required for any upgrade project, even a simple widening to add a median strip. I'm not too sure about what will happen with the power station though.

Mr Smith's post (which I hadn't yet read) clears this up much better that I have tried though.

From a source within Dept Transport & Infrastructure, the plan for South Rd between Regency Rd and Anzay Hwy is finished and is either with the Govt for consideration, or soon will be. The 'corridor' will be the existing South Rd and for the section between Torrens Rd and Port Rd, most if not all of the properties on the western side of South Rd are owned by Dept Transport. The section between Outer Harbour railway line and south of Grange Road will be dealt with by way of a trench rather than a tunnel as prev planned. I gather there are a couple of options for the section south of Grange Rd to Anzac Hwy, trench v tunnel, although was not able to get anything more specific, other than that this section will definitely NOT be elevated, as most of us probably knew already, as would be political suicide for the State Govt. The road will be a 'non stop' corridor, however speed limits will be relatively low, probably 60 - 80kph, due to the frequency on merging traffic, particularly the section between Henley Beach rd and Anzac Hwy. Probably a comparable road treatment would be South Dowling St in Eastern Sydney.

There has been no detailed planning between Anzac Highway and the Southern Expressway.

Well this is a great start. I look forward to seeing official plans for all this, hope they're available to public by the end of the year! This is the WHOLE section (Anzac-Regency) non stop? Guess that means it will even remove Hawker, Pym, George Roads. And pedestrian crossings. That's a lot to achieve! Even if they start construction right after they finish the superway, I can't see them being finished this section until 2020, without working on the whole section at once.

[Mr Smith]

Re previous post, one thing i neglected to add, but which is fairly self evident from the parlous state of our budget, is that nothing is expected to happen anytime soon unless the Feds kick in and the split is 80/20 or something like that. As the federal budgetary position is pretty ordinary as well, we could be waiting a fair while.

[claybro]

I cant understand all the excitement of this upgrade if it pans out as stated. 60-80km/h is not sufficent to get large volumes of traffic moving particularly for vehcles travelling the whole length. Even arterial roads in other Australian cities have at least a 70-80km/h with traffic lights or not. I wont go on about this in this thread, but rest assured in 20 years when/if this upgrade is finished, it wont even go close to being adequate.