[U/C] M2 North-South Motorway

[Nort]

The project includes:
A 4.3km southern tunnel from Darlington to just south of the Glenelg Tram bridge

• 1km of lowered motorway under the Glenelg Tram line and Anzac Highway
  2km surface motorway from Anzac Highway to just south of Richmond Road then a lowered motorway under Richmond Road
  A 2km northern tunnel under Sir Donald Bradman Drive ending just south of West Thebarton Road
  1.1km of lowered motorway under West Thebarton Road until south of the River Torrens and then a surface motorway until the tie-in with the Torrens to Torrens section

The decision to build the northern tunnel will spare landmarks previously under threat including Thebarton Theatre, Queen of Angels Church, Hindmarsh Cemetery and the Hoffman Brick Kiln.

Measuring out those distances on a map means there will likely be an exchange around James Congdon Drive. I'm curious what this Airport Link talk is, just selling up the ability the get onto Sir Donald Bradman or I wonder if they'll be doing something with Richmond Road.

Also it's kinda funny they say that the tunnel solution will spare landmarks like the kiln and the cemetery when the tunnel stops before them anyway.

[croweater888]

https://dit.sa.gov.au/nsc/torrens_to_da ... _questions

[Spotto]

How is the setup at Emerson going to work, given that the support pylons of the current overpass are in the way of the tunnel, unless the tunnels deviate to the left or right of the structure? Also it rules out any railway underpass or overpass, so that's just bungling any chance of a grade seperation in that area.

There's a few other concerns I have, but Emerson is the main one I'll provoke some discussion for now.

Emerson Overpass was flawed from its inception since it failed to grade separate the railway as well. Presumably the overpass will be demolished and replaced to accomodate the motorway tunnel and an interchange with Cross Road. It would also give them the opportunity to grade separate the railway line; the tunnels will likely be made deep enough or deviate around the site to allow whatever solution is devised.

[Listy]

The project includes:
A 4.3km southern tunnel from Darlington to just south of the Glenelg Tram bridge

• 1km of lowered motorway under the Glenelg Tram line and Anzac Highway
  2km surface motorway from Anzac Highway to just south of Richmond Road then a lowered motorway under Richmond Road
  A 2km northern tunnel under Sir Donald Bradman Drive ending just south of West Thebarton Road
  1.1km of lowered motorway under West Thebarton Road until south of the River Torrens and then a surface motorway until the tie-in with the Torrens to Torrens section

The decision to build the northern tunnel will spare landmarks previously under threat including Thebarton Theatre, Queen of Angels Church, Hindmarsh Cemetery and the Hoffman Brick Kiln.

Measuring out those distances on a map means there will likely be an exchange around James Congdon Drive. I'm curious what this Airport Link talk is, just selling up the ability the get onto Sir Donald Bradman or I wonder if they'll be doing something with Richmond Road.

Also it's kinda funny they say that the tunnel solution will spare landmarks like the kiln and the cemetery when the tunnel stops before them anyway.

The fact that cemetery will be saved is informative - it suggests that the current bridge over the Torrens will be widened on the western side of South Rd, not the eastern side (which makes sense, there's a lot more space on that side).

The Airport Link is mentioned in the airport master plan - its an extension of Richmond Rd into the airport - a transit/taxi corridor into the existing terminals would be built plus a new freight specific terminal on the eastern edge of the airport. How that gets tied into the interchange at Bradman I don't know, having another interchange at Richmond Rd seems unlikely as it is only a few hundred metres away.

[ChillyPhilly]

I think it will be a split interchange, as identified in the Scoping Report. Two ramps at Sir Donald Bradman Drive, and the other two at Richmond Road.

[TorrensSA]

The "1.1km lowered motorway under West Thebarton Road" means it will start around George Street. I'm guessing the tunnel will transition into a lowered motorway. I wonder how many houses in West Thebarton / East Torrensville will be lost. The scenario put up seems decent though, you need to somehow get out of a tunnel and up across the river, I don't think it needs to be so long though, it could start at Ashley Street, theres plenty of commercial buildings on the east side that can be taken out and build the motorway under West Thebby.

[NYG]

Now we have to hope the Libs don't butcher this and give us two tunnels that are only two lanes wide.

Here's a render from the State Budget Overview.

From the FAQ section:

“How many lanes will the tunnels be when they open to traffic?

This will be determined as we continue to develop the design, update our traffic modelling and engage with key stakeholders. We expect the tunnels to be built for at least two lanes in each direction.”

[Spotto]

From the FAQ section:

“How many lanes will the tunnels be when they open to traffic?

This will be determined as we continue to develop the design, update our traffic modelling and engage with key stakeholders. We expect the tunnels to be built for at least two lanes in each direction.”

Not good enough, especially considering the rest of the motorway and the Reynella to Darlington section of the Southern Expressway are all 3 lanes. T2D will be the core of the motorway and will likely be the busiest section, 3 lanes at a minimum (though I doubt it would be more than 3) otherwise we’ll be back to square one in a decade or so.

[Nort]

Bit of a tangent but it's also interesting to wonder what this tunnelling could mean for future projects. If we have that equipment and expertise built up locally the CBD rail proposals become a lot more plausible.

[ChillyPhilly]

The height of the tunnel will be determined by a number of factors, including the number of tunnel lanes required. The number of lanes will determine the diameter of the Tunnel Boring Machines (TBM) in addition to freight and High Productivity Vehicle height needs.

While the diameter of TBMs can vary, it is estimated that the machines we will use will be around 15 metres.

15m TBMs are pretty big.

This link provides some context and comparable examples.

https://www.tunneltalk.com/Discussion-F ... -world.php

[Eurostar]

How is the setup at Emerson going to work, given that the support pylons of the current overpass are in the way of the tunnel, unless the tunnels deviate to the left or right of the structure? Also it rules out any railway underpass or overpass, so that's just bungling any chance of a grade seperation in that area.

There's a few other concerns I have, but Emerson is the main one I'll provoke some discussion for now.

Emerson Overpass was flawed from its inception since it failed to grade separate the railway as well. Presumably the overpass will be demolished and replaced to accomodate the motorway tunnel and an interchange with Cross Road. It would also give them the opportunity to grade separate the railway line; the tunnels will likely be made deep enough or deviate around the site to allow whatever solution is devised.

I take it Emerson Overpass was an after thought or prior to something like the MATS plan which would of meant a whole different lot of freeways, like the one that was to follow the former Glenelg tramway going through Plympton then south to Darlington and the hills connector one.

[ChillyPhilly]

The Emerson overpass was built in 1984, and was at the time considered a bit of a resurgence of the ideas of the MATS Plan.

Certainly, a full grade separation is required here, and the existing overpass is not suitable for motorway traffic.

Labor's plan in the Scoping Report was for a 'duplication' of the bridge. The main complication of the immediate area, which was identified, was the Telstra substation. Relocation of this could take up to five years as this is how long rebuilding the network would take.

[Spotto]

The Airport Link is mentioned in the airport master plan - its an extension of Richmond Rd into the airport - a transit/taxi corridor into the existing terminals would be built plus a new freight specific terminal on the eastern edge of the airport. How that gets tied into the interchange at Bradman I don't know, having another interchange at Richmond Rd seems unlikely as it is only a few hundred metres away.

For anybody interested, I found the 2019 Draft Master Plan which includes several mentions of eastern access via Richmond Road and a few diagrams of possible roadways including the Richmond Road link. It would turn north from Richmond Road and follow the creek up the eastern boundary to join an improved "Security Road" (currently an internal access road) which connects to Comley Street which would be linked to the roundabout by a short road link.

The North-South Corridor is one of Adelaide’s most important transport corridors. Its connection to Adelaide Airport has the potential to significantly improve accessibility and travel times for passengers. Connections to the Airport East Precinct from the future North-South Corridor via Richmond Road will also see improved efficiencies and benefits for south Australia’s freight network. Plans for future road connections between the airport and the upgraded North-South Corridor will be determined by the State Government in consultation with AAL.

[SBD]

The height of the tunnel will be determined by a number of factors, including the number of tunnel lanes required. The number of lanes will determine the diameter of the Tunnel Boring Machines (TBM) in addition to freight and High Productivity Vehicle height needs.

While the diameter of TBMs can vary, it is estimated that the machines we will use will be around 15 metres.

15m TBMs are pretty big.

This link provides some context and comparable examples.

https://www.tunneltalk.com/Discussion-F ... -world.php

The Heysen tunnels are three lanes each. An archived web page says they were dug by an SW200 tunnelling machine at a rate of 3m/day, but doesn't give any more details of diameter etc.

[how good is he]

Anyone have an idea/want to speculate the likely areas where properties will be compulsorily acquired ..... 390 properties in total.