Sensational-Adelaide.com

Proposal for a new East-West Link connecting the South Eastern Freeway to the North-South Motorway.

Consisting of 8.5km long twin tunnels, comprising of 3 lanes each way, running underneath Edward Street and Grange Roads in the inner southern suburbs, from the South Eastern Freeway at Mount Osmond to the Raglan Avenue intersection at Edwardstown. Compulsory property acquisition would be limited to the former Hills site at Edwardstown.

Speed limit 100kph. Travel time between the South Eastern Freeway and North South Motorway would be approx. 5-6 minutes. There are no interchanges in between. It would bypass 12 sets of traffic lights along Cross Road and the Adelaide Metro / ARTC freight train crossing at Unley Park. Travel time savings of approx. 10 minutes in off peak and 20 minutes in peak hour.

Not sure about estimated construction costs given they vary wildly, but some similar recent motorway tunnel projects in Australia have been costed at:

WestConnex M5, Sydney - 9kms. $4.3b
T2D, Adelaide - 10.5kms. $15.2b
West Gate Tunnel, Melbourne - 4kms, $11.9b.

Maps made using anyways.eu - you can use OSM data to create custom maps for a free two week trial.

What's the solution to trucks losing their brakes on the decent from Crafers?

The arrestor beds are there now, but the odd truck still ends up at the Tollgate intersection. What's to stop out of control trucks from entering the tunnel?

I'll admit it's a conundrum, you could extend the East West Link further up the freeway, but that adds to the construction costs. The arrestor bed may well need to be a fourth lane within the tunnel entrance itself with cushioned walls.

Really, any tunnel would need to start around Bridgewater to avoid the worst of the grades. But then you're tunnelling 10km further which obviously isn't viable.

If the solution was easy/cheap, I'm sure it would have been implemented by now.

Does anyone know the history of why the main route to Melbourne goes via the highest part of the Ranges?

Looks interesting Shuz, I'm curious to see how it would look with the topography, well it be all underground or are there sections that will be above ground?

I also wonder if gravel arrestor beds are allowed inside tunnels. The bed does not need to go uphill, the one at the Southern Expressway doesn't.

The route has already factored in topography, the entire motorway would be tunnels.

Why is this even needed when both Labor and Liberals are co-funding a $850M freight bypass east of the Adelaide Hills?
Better to spend this money on public transport.

ml69 wrote: ↑

Fri Apr 11, 2025 7:25 am

Why is this even needed when both Labor and Liberals are co-funding a $850M freight bypass east of the Adelaide Hills?
Better to spend this money on public transport.

Because only a fraction of vehicles coming down the freeway will use the bypass. A truck going from Tailem Bend to Outer Harbor isn't going to take the scenic route via Truro. They'll take Cross Rd, into the tunnel and through to the PREXY.

The whole reason they're trying to do a bypass anyway is because they don't want to upset the precious residents in the inner south and eastern suburbs.

The rest of Adelaide and surrounds should suffer because the selfish, entitled, arrogant, living beyond their means to keep up with the Jones' residents particularly around Cross Rd and Portrush Rd will kick up a huge stink if the government proposes anything.

They are happy to use the NSM when it's convenient for them though.

If the inner south/eastern suburbs residents are that opposed to motorways tunnelled or otherwise running through their area, but are happy to use the motorways running through other parts of the metropolitan area, then they should be slugged a toll based on their post code.