[COM] M2 Northern Connector | 15.5km | $867m

[Hooligan]

Surely upgrading that section of Salisbury highway would cost next to nothing?

[drsmith]

Surely upgrading that section of Salisbury highway would cost next to nothing?

A 7.2km one lane widening of the northbound carriageway of the Mitchell Freeway in Perth's northern suburbs was slated to cost $30m. This project also included resurfacing of existing lanes and is now either complete or very close to it.

https://www.mainroads.wa.gov.au/Buildin ... chell.aspx

The extra lane was constructed in the central median between the existing northbound carriageway and the rail line. Very little service relocation would have been required and widening that section Salisbury highway I suspect would be similar in this regard.

[Hooligan]

So if this project doesn't happen for a while that's a perfect stop gap.

[ChillyPhilly]

Chuck in an entry/exit to Montague Road for an additional few million or so to reduce pressure further along PW Road and through Mawson Lakes, and then we're talking.

[Westside]

Chuck in an entry/exit to Montague Road for an additional few million or so to reduce pressure further along PW Road and through Mawson Lakes, and then we're talking.

Yes! Why did this not occur 10 years ago? I understand that this would require a bridge over the railway and either an interchange or traffic lights on the existing Salisbury Hwy Extension. However, this seems to me like a fairly simple addition to the network to complement the Montague Rd extension through to Churchill Rd Nth and take a huge burden of E-W traffic off PW rd.

[monotonehell]

Chuck in an entry/exit to Montague Road for an additional few million or so to reduce pressure further along PW Road and through Mawson Lakes, and then we're talking.

Yes! Why did this not occur 10 years ago? I understand that this would require a bridge over the railway and either an interchange or traffic lights on the existing Salisbury Hwy Extension. However, this seems to me like a fairly simple addition to the network to complement the Montague Rd extension through to Churchill Rd Nth and take a huge burden of E-W traffic off PW rd.

I just looked at a map, this seems anything but simple.

[ChillyPhilly]

Chuck in an entry/exit to Montague Road for an additional few million or so to reduce pressure further along PW Road and through Mawson Lakes, and then we're talking.

Yes! Why did this not occur 10 years ago? I understand that this would require a bridge over the railway and either an interchange or traffic lights on the existing Salisbury Hwy Extension. However, this seems to me like a fairly simple addition to the network to complement the Montague Rd extension through to Churchill Rd Nth and take a huge burden of E-W traffic off PW rd.

I just looked at a map, this seems anything but simple.

Unfortunately. In the MATS Plan, the current PRExy/Salisbury Highway corridor was originally intended to continue east onto Montague Road. This is why Montague Road has significant space along its north and south shoulders.



This alone shows the immense difficulties in creating a said entrance and exit. It'd probably have to go as direct as possible and tunnel it. Going on the surface is too difficult, especially given the wetlands, railyards (still brand spankin' new), the freight line, industrial property and so on. The only other alternative is to use up part of Churchill Road North west of Port Wakefield Road to go less direct.

[Aidan]

Elevated would be much cheaper than tunnelling, and utilizing Churchill Road North would be about half the distance (hence half the cost) of going direct.

[ChillyPhilly]

Cheaper, yes. More visually impacting, yes. More viable? Only if we're to think in financial terms.

[Hooligan]

There is no way what so ever you could justify a tunnel in an industrial area like that.

Elevated would be more than sufficient.

[Westside]

This doesn't have to be a freeway-grade rd, just a regular 4 lane main rd would be enough to bridge the small gap between the Salisbury Hwy and Churchill Rd North, then upgrade Churchill Rd north to a 4 lane main rd too. Before the construction of the Dry Creek rail depot, this would have been relatively simple - follow the existing Northfield Line then a bridge over the current rail line. That's pretty much all it needed to be. Now with the rail depot in the way, it's a bit trickier - the crossing over the rail line would need to be closer to dry creek station.

[drsmith]

This doesn't have to be a freeway-grade rd, just a regular 4 lane main rd would be enough to bridge the small gap between the Salisbury Hwy and Churchill Rd North, then upgrade Churchill Rd north to a 4 lane main rd too. Before the construction of the Dry Creek rail depot, this would have been relatively simple - follow the existing Northfield Line then a bridge over the current rail line. That's pretty much all it needed to be. Now with the rail depot in the way, it's a bit trickier - the crossing over the rail line would need to be closer to dry creek station.

Grade separation would also be required on the eastbound carriageway over Salisbury Highway to avoid traffic signals there.

East of the railway line, a new 4-lane road could be constructed on an alignment just north of Churchill Road North and connect into the existing PWR/Montague Road Intersection. A new 4-way signalised intersection would need to be constructed at Bradford Way to maintain local business access. Churchill Road North west of Bradford way would also need to be maintained somewhat as is as a local access road and would make up the fourth leg of the new signalised intersection with Bradford Way.

This would be a costly project and I wonder whether it could ever be justified given the existing grade separated access over PWR north of the Railway towards Salisbury and Elizabeth.

[ChillyPhilly]

That PWR/Salisbury Hwy intersection could use a bit of reworking. Always hated it.

[Goodsy]

That PWR/Salisbury Hwy intersection could use a bit of reworking. Always hated it.

I go through it everyday, the only time it gets backed up is when someone breaks down and closes one of the lanes. Which happens every other week

[drsmith]

That PWR/Salisbury Hwy intersection could use a bit of reworking. Always hated it.

That interchange I suspect was never designed to be upgraded from its present configuration.

The overpass camber angles as viewed from under the bridge for example suggests to me that the overpass itself was not designed to be duplicated. This would have been necessary for the current signals at PWR to be removed and the right turn movements accommodated by loop ramps.

This interchange I imagine would have been looked at when upgrading a section of PWR to a freeway was considered as part of the Northern Expressway project. That though died in favour of the interim upgrade and the longer term Northern Connector project.

The interchange design strikes me as being efficient in that by denying the low volume acute right turn movements at grade, the signals are effectively only 2-phase thus maximising the remaining movements. Efficiency if further enhanced by the two right turn movements to exit PWR not being in conflict as is the case with the at grade component of a typical diamond. It's effectively a SPUI with one set of right turn movements removed and the other two able to operate independently. All this without having to have a continuous uninterrupted deck for the at grade component.

I love this interchange.

With the Northern Connector designed to do the heavy lifting in relation to future road transport through that area, I doubt it will be significantly modified in the foreseeable future.