[COM] Goodwood/Springbank/Daws Road Intersection Upgrade

[NTRabbit]

I was under the impression that the Britannia Roundabout issue was finished as is? Every time I've been through there lately the traffic has flowed and it's been easy to get through there.

They "finished" their low cost alternative to an underpass of splitting it into two roundabouts, but I read that reports suggest the data shows it ultimately hasn't changed anything, the accidents are still high and the traffic is still bad.

[Waewick]

I was under the impression that the Britannia Roundabout issue was finished as is? Every time I've been through there lately the traffic has flowed and it's been easy to get through there.

They "finished" their low cost alternative to an underpass of splitting it into two roundabouts, but I read that reports suggest the data shows it ultimately hasn't changed anything, the accidents are still high and the traffic is still bad.

As someone who uses it daily, i have no idea how anyone could think this was a good roundabout.

It is fine off peak, but the moment there is any semblance of traffic it is stuffed.

[ChillyPhilly]

It needs to be modified to the 'keyhole' arrangement.

[Waewick]

It needs to be modified to the 'keyhole' arrangement.

To me, Fullarton Road going east should be diverted down Flinders Rd (heading towards Bartels). Dequitivalle terrace is wide enough to accommodate 4 lanes going east which you could merge to three (so two turning lanes, either with lights or turn with care)

You then turn Wakefield and Dequitivalle Tce into a proper intersection with no access from Fullarton road.

The ring route would be quicker and reduce the congestion at this intersection with traffic lights (or an under pass), you'd also clean up the intersection at Fullarton/Parade.

[EBG]

All they have to do is use the same plan that was used to realign Regency Rd and Muller Rd at the intersection with Hampstead Rd. its not rocket science.
check it out on Google maps
https://www.google.com/maps/@-34.872356 ... 312!8i6656

[TorrensSA]

There's no way a realigned dog-leg intersection can be quicker than a standard cross intersection. The east-west traffic via the dog leg will always take longer to clear than a standard intersection, therefore traffic going north-south will be forced to wait longer.
If the lights are continuous a car going through the dog leg will take FIVE times as long to clear the intersection compared to a standard intersection, the dog leg is about 150m, which will take you at least 15 seconds to clear, compared to a standard intersection which is about 25m wide which takes 3 seconds to cross. There might be some strange number magic by the gov't but I can't see how a more complicated option is quicker .

[SBD]

There's no way a realigned dog-leg intersection can be quicker than a standard cross intersection. The east-west traffic via the dog leg will always take longer to clear than a standard intersection, therefore traffic going north-south will be forced to wait longer.
If the lights are continuous a car going through the dog leg will take FIVE times as long to clear the intersection compared to a standard intersection, the dog leg is about 150m, which will take you at least 15 seconds to clear, compared to a standard intersection which is about 25m wide which takes 3 seconds to cross. There might be some strange number magic by the gov't but I can't see how a more complicated option is quicker .

Someone on this forum used to tell us that the control system for the traffic lights has a lot of features that aren’t used in Adelaide to their full effect. The plan appears to be to set up the lights as a single intersection, but that may not mean that the red lights at each end have to be at exactly the same time. We don’t have information on turning movements at this intersection(s), so don’t know if most people are turning on/off of Goodwood Road, or if there is a lot of crossing traffic. Even less do we know what effects will come from building the nearby part of the north-south motorway.

I noticed one change from now to the future state after combining two intersections into one is that the pedestrian crossings are moved to the outsides of the dogleg. That means that people will be able to cross Goodwood Road at the same time as cars are crossing between Daws and Springbank Roads. It also makes crossing Goodwood Road a two-stage walk so one direction of traffic can cross while pedestrians are only crossing the other side. Those changes likely provides some of the east-west improvement.

[EBG]

You can always curve the approach roads so the they intersect exactly at right angles if you are prepared to buy more land initially. I would dispute the times to cross 90 deg and other angle intersections. Every morning and night I travel along Greenhill Rd and the time taken to cross Glen Osmond Rd (at an angle) compares with the time taken to cross Unley Rd and also to cross Goodwood Rd. Also Richmond road is curved just before Anzac highway to meet Greenhill road in a Straight line. I will have to start timing my trip to & from work. ( I do know it is actually quicker by bike than by driving ).

[Furyan]

I personally cannot see how a dogleg ( sorry staggered T ) can be more efficient than a 4 way intersection if you are comparing apples with apples.

Did the traffic modelling of both plans have the extra lanes and extra lane storage capacity or was the Liberals plan modelled against Labors concept plan.

While the Liberals are saying the modelling doesn't lie it can be manipulated to get a desired outcome.

[OlympusAnt]

Britannia is fine unless you have idiots from Fullarton Rd southbound that just roar through with pace and expect everyone to stop

[SBD]

I personally cannot see how a dogleg ( sorry staggered T ) can be more efficient than a 4 way intersection if you are comparing apples with apples.

Did the traffic modelling of both plans have the extra lanes and extra lane storage capacity or was the Liberals plan modelled against Labors concept plan.

While the Liberals are saying the modelling doesn't lie it can be manipulated to get a desired outcome.

It doesn't have to be better - it only has to be "just as good" and cheaper.

The challenge for modelling would be on what timeframe's traffic?

• Before they started work on Darlington interchange
• Current
• Projected post-Darlington
• Projected during or after Anzac Highway-to-Darlington upgrade
• With what projected future works on or about Cross Road?

I expect they would all be different, especially the make up of through- and turning-traffic. Perhaps it's better to find a solution that is good enough for now without significant property acquisition, and see how the demand changes after the money not spent buying property here has been spent doing work on the North-South Corridor a year earlier.

[Patrick_27]

I personally cannot see how a dogleg ( sorry staggered T ) can be more efficient than a 4 way intersection if you are comparing apples with apples.

Did the traffic modelling of both plans have the extra lanes and extra lane storage capacity or was the Liberals plan modelled against Labors concept plan.

While the Liberals are saying the modelling doesn't lie it can be manipulated to get a desired outcome.

It doesn't have to be better - it only has to be "just as good" and cheaper.

The challenge for modelling would be on what timeframe's traffic?

• Before they started work on Darlington interchange
• Current
• Projected post-Darlington
• Projected during or after Anzac Highway-to-Darlington upgrade
• With what projected future works on or about Cross Road?

I expect they would all be different, especially the make up of through- and turning-traffic. Perhaps it's better to find a solution that is good enough for now without significant property acquisition, and see how the demand changes after the money not spent buying property here has been spent doing work on the North-South Corridor a year earlier.

You also have to consider disruption, which Labor's plan is far less disruptive because most of the works can be done to the side and only once that is complete would some minor transitional works need to be done (these could be done at night. Adding lanes and such is going to snail pace this entire section of road which is already crawling during peak hour. Just trying to get onto Daw Road on the southbound lane is f*cked because the lights are poorly sequence with one another.

[Vasco]

As a local / daily user of this intersection, I went to the information briefing at Pasadena HS a few weeks ago, hosted by the relevant state / federal liberal members, Minister Knoll & DPTI. A few main points to make;

There was a previous session held late last year, where interested local parties were told DPTI would be investigating designs for consultation with the local stakeholders at a later date. Turns out to the outrage of attendees, they have basically made up their mind and will be proceeding with the proposed design, rather than coming back for consultation of design options.

Although the Liberals have said Labor’s proposal was merely a sketch on the back of an envelope. The liberals/DPTI have basically said this new Dog Leg design is superior to any other design, without even undertaking any other detailed design options (eg 4 way intersection). They did not even have a costing on the labor style 4 way design.

All they had done is some number based modelling based on traffic flows and came to the conclusion that this is the superior design.

The current waiting times and future times saved (as above) are also lacking in specific detail and to me seems like it has been cherrypicked to suit their proposal.

There was no detail as to which properties may be affected by any acquisition.

In the face of strong scepticism, the demeanour of the elected ‘representatives’ was disappointing to say the least.


Sent from my iPhone using Tapatalk

[ChillyPhilly]

As a local / daily user of this intersection, I went to the information briefing at Pasadena HS a few weeks ago, hosted by the relevant state / federal liberal members, Minister Knoll & DPTI. A few main points to make;

There was a previous session held late last year, where interested local parties were told DPTI would be investigating designs for consultation with the local stakeholders at a later date. Turns out to the outrage of attendees, they have basically made up their mind and will be proceeding with the proposed design, rather than coming back for consultation of design options.

Although the Liberals have said Labor’s proposal was merely a sketch on the back of an envelope. The liberals/DPTI have basically said this new Dog Leg design is superior to any other design, without even undertaking any other detailed design options (eg 4 way intersection). They did not even have a costing on the labor style 4 way design.

All they had done is some number based modelling based on traffic flows and came to the conclusion that this is the superior design.

The current waiting times and future times saved (as above) are also lacking in specific detail and to me seems like it has been cherrypicked to suit their proposal.

There was no detail as to which properties may be affected by any acquisition.

In the face of strong scepticism, the demeanour of the elected ‘representatives’ was disappointing to say the least.

A community and stakeholder engagement failure, sad.

[[Shuz]]

Community group rejects government’s $35m plan for Springbank intersection
APRIL 03, 2019

The community group pushing for an upgrade at the Goodwood/Springbank/Daws road intersection has rejected the newly announced $35 million plan by the federal and state Liberal governments.

Neil Baron, of the Panorama Clapham Community Group (PCCG), said its modelling had shown retaining the two T-junctions — as proposed by the governments — would result in a “white elephant”.

Mr Baron conceded his group’s modelling was “simplistic” but still “far more detailed than anything the government has produced so far”.

Over the past month, federal Labor and Liberal have each pledged funding to fix the trouble-plagued dogleg should their party win the next election.

The PCCG modelling compares the Liberals’ $35 million double T-junction option with Labor’s $30 million four-way intersection proposal.

“Any responsible government would want to compare the two options so we’re helping them out,” Mr Baron said.

“People are ropeable right now. They are sick of being sold a pup and they know the government plan is a total waste of money. This is a poor attempt to sell something that is unsellable.”

Mr Baron double T-junctions were being phased out everywhere. “You’ve got a bottleneck now and … you’re still going to have two sets of lights,” he said.

“You’re going to have more north/south traffic flow at the expense of east/west which is currently the problem when you’re trying to get from Daws Rd to Springbank Rd.”

Mr Baron was one of more than 100 people who last month attended a community forum to discuss the intersection upgrade with state Transport Minister Stephan Knoll, state MPs Carolyn Power and Sam Duluk, and Nicolle Flint, MP for the marginal federal seat of Boobthy.

“Minister Knoll was repeatedly asked to make public both the modelling and the report he quoted which showed why his double T-junction was the best option but to date it has not been released to the public, “ he said.

Mitcham Mayor Heather Holmes-Ross backed Mr Baron’s call for the release of the traffic modelling.

“Mitcham has asked the State Government for the modelling to be presented at a public briefing (in) April,” Dr Holmes-Ross said.

“We want to understand why the government thinks a staggered intersection is the best option.

“Once we have received the traffic modelling information we will be able to comment on the best option.”

She said her council had been lobbying for an upgrade at the intersection for many years and is keen to keep working with government to identify “the best option”.

“Our focus is to improve east/west traffic movement,” she said.

Mr Baron said PCCG had invited all four MPs to its community meeting at the Clapham Primary School at 7pm on Thursday (April 4) but was yet to received an affirmative response.

Dr Heather Holmes-Ross said she would attend the PCCG meeting.