[U/C] M2 North-South Motorway

[Llessur2002]

Just re-floating the map I knocked up last year and some comments on the distances quoted in the project description:

So here's what I think we'll end up with, or thereabouts (thanks Windows Paint).



A couple of the distances for the sections don't check out exactly as reported:

A 2km surface motorway from Gallipoli Underpass to just south of Richmond Road then a lowered motorway under Richmond Road until the beginning of the northern tunnel, just south of Sir Donald Bradman Drive.

and

A 1.1km lowered motorway under West Thebarton Road, stretching to south of the River Torrens and then a surface motorway from the river to the Torrens to Torrens section of the project.

I think these measurements are for the combined portions i.e. the 2km stretch comprises both a surface motorway Gallipoli Underpass AND the lowered section from just south of Richmond Road and the 1.1km stretch comprises the lowered motorway under West Thebarton Road AND the surface road up to the existing T2T.

So, yes, the main surface/lowered elements will be between Anzac Highway and SDB Drive but it is only the southern half of this between Anzac Hwy and Richmond Road (around Kurulta Park, Ashford, Everard Park etc) that is remotely tree-lined and even then it's only with plane trees on one side. North of Richmond Road is pretty barren. There are very few residential properties fronting South Road anywhere along this stretch.

[claybro]

Looks about right. And I wasn’t meaning to imply that that surface section proposed is currently some tree lined boulevard, I guess I’m just curious as to why they have proposed such a long tunnel, through some pretty average commercial space, but then pop up to the surface for a mere 2km slap bang in some fairly tight suburbia. At least they could have continued the trench. Less noise problems, and less like a roller coaster. Every incline involves trucks accelerating/decelerating, creating noise and pollution which is crazy in a flat city like Adelaide.

[Nort]

Looks about right. And I wasn’t meaning to imply that that surface section proposed is currently some tree lined boulevard, I guess I’m just curious as to why they have proposed such a long tunnel, through some pretty average commercial space, but then pop up to the surface for a mere 2km slap bang in some fairly tight suburbia. At least they could have continued the trench. Less noise problems, and less like a roller coaster. Every incline involves trucks accelerating/decelerating, creating noise and pollution which is crazy in a flat city like Adelaide.

All that commercial space probably would have cost more to acquire than the extra cost of the tunnel.

[claybro]

Looks about right. And I wasn’t meaning to imply that that surface section proposed is currently some tree lined boulevard, I guess I’m just curious as to why they have proposed such a long tunnel, through some pretty average commercial space, but then pop up to the surface for a mere 2km slap bang in some fairly tight suburbia. At least they could have continued the trench. Less noise problems, and less like a roller coaster. Every incline involves trucks accelerating/decelerating, creating noise and pollution which is crazy in a flat city like Adelaide.

All that commercial space probably would have cost more to acquire than the extra cost of the tunnel.

Not even close. And then by that logic, why not tunnel the other 2km? -the whole corridor should be tunnel if it is more cost effective.

[aceman]

at this stage the plan is for a lowered motorway under the glenelg tram line and anzac highway.

my question is would the tram overpass need to be completely removed and rebuilt if that section is widened for new surface roads and a new trench?

[Nort]

Looks about right. And I wasn’t meaning to imply that that surface section proposed is currently some tree lined boulevard, I guess I’m just curious as to why they have proposed such a long tunnel, through some pretty average commercial space, but then pop up to the surface for a mere 2km slap bang in some fairly tight suburbia. At least they could have continued the trench. Less noise problems, and less like a roller coaster. Every incline involves trucks accelerating/decelerating, creating noise and pollution which is crazy in a flat city like Adelaide.

All that commercial space probably would have cost more to acquire than the extra cost of the tunnel.

Not even close.

What's your cost estimates?

[AG]

at this stage the plan is for a lowered motorway under the glenelg tram line and anzac highway.

my question is would the tram overpass need to be completely removed and rebuilt if that section is widened for new surface roads and a new trench?

Not necessarily if the surface/lowered roads correspond with the current widths of the tram bridge spans. The lift and tram stop access might need relocating though.

[claybro]

All that commercial space probably would have cost more to acquire than the extra cost of the tunnel.

Not even close.

What's your cost estimates?

Number of properties to be acquired v average price per property in the area will give a fair indication. We already know the cost of trenching and acquisition from the T2T section approx $200 million per kilometre-albeit for less properties acquired in that stretch. The remaining stretch of 11km is to be around $9 Billion? So considerably more per kilometre- but obviously far less disruptive- so the social cost has to be taken into consideration. Two things come to mind-if it is good enough to spend the extra money not to disrupt the businesses and homes of Edwardstown by a tunnel through that section-why not use tunneling through the Anzac-Mile end South section. If as you say it is cost comparative-then tunnel the whole thing. If in fact cost has come into it-then I think they will need to explain this to the people living near the surface section.

[Eurostar]

Wouldn't surprise me if the Opposition opts for a trench in between Tonsley and Edwardstown.

[ChillyPhilly]

Wouldn't surprise me if the Opposition opts for a trench in between Tonsley and Edwardstown.

This would be interesting. The Scoping Report called for an elevated road along this stretch.

[VLtom]

As the tunnel is going underneath crossroad/south road intersection I'm wondering how much is going to be done to that part. That overpass being 40 years old doesn't exactly make it life expired, but we're not going to lose anything by demolishing it, but it also has to be within the scope the NCS to finally remove the rail line from that section.

That intersection will be the last major grade crossing on the line when Hove gets removed so it would make sense to remove it and maybe straighten out the curve at Edwardstown which is much too sharp, maybe also incorporate Edwardson and Emerson station into one over the intersection as they're currently only 700 metres apart.

[Spotto]

Just re-floating the map I knocked up last year and some comments on the distances quoted in the project description:

The lowered expressway at Darlington already rises at Ayliffes Road then descends under Tonsley Boulevard to rise back up to the current South Road. Surely they'd build the new section so that the Tonsley Boulevard underpass would essentially be extended as lowered motorway to meet the tunnel portals, and not have the finished motorway rise back up after Tonsley only to descend again (deeper) to the tunnels?

[rhino]

If as you say it is cost comparative-then tunnel the whole thing. If in fact cost has come into it-then I think they will need to explain this to the people living near the surface section.

Making exits out of the tunnel is a lot more expensive than making an exit off a trench or elevated road (or an at-grade road). This means that if you want to access any of the main roads between Ayliffes Road and the River Torrens, you would have to use the surface road from one of those exits. Sort of self-defeating.

[ChillyPhilly]

Just re-floating the map I knocked up last year and some comments on the distances quoted in the project description:

The lowered expressway at Darlington already rises at Ayliffes Road then descends under Tonsley Boulevard to rise back up to the current South Road. Surely they'd build the new section so that the Tonsley Boulevard underpass would essentially be extended as lowered motorway to meet the tunnel portals, and not have the finished motorway rise back up after Tonsley only to descend again (deeper) to the tunnels?

It will definitely be interesting.

I know the preference is for the corridor to expand eastward around Edwardstown (hence why Bunnings was built on the western side of the road).

There is a substation on the corner with Daws Road, so one would imagine there'd be a tunnel here.

[NTRabbit]

Another election promise from 2018 the Liberal government has now officially ditched, the on-off ramp at Majors Rd.