Do these forecasts make any sense?

These are the traffic forecasts from the Linking Melbourne Authority’s Impact Statement on the East West Link.

Given they are a public “Authority”, not just a promoter of a highly dodgy scheme, you would expect these to be dispassionate objective analysis.

But wait, under the Major Transport Facilitation Act they have also been appointed as the “Project proponent” so the lines are a little blurred.

Leaving aside questions of objectivity, what are they claiming for traffic reductions from the East West Link? In a nut shell:

 Even if the East West link is built, there will be more traffic on Alexandra Parade in 2031 than today.


Exhibit A: Change in Traffic in 2031 if no tunnel is built.

Traffic in 2031 if no EWL built

This shows that Alexandra Parade is predicted to have an increase of at least 20% and as high as 50%. [but see comment below]

This is assuming no road tunnel, no train improvements and no mass ecological collapse or economic shocks. The business as usual case.

Exhibit B shows the predicted traffic if the East-West Link were built. Predictably Alexandra Parade has less orange, but it is still carry higher traffic than today.

Traffic in 2031 if EWL built

Alexandra Parade is still orange! Even if the East West link is built, there will be 10% more traffic on Alexandra Parade in 2031 than today. And therefore it will probably be just as slow as today. Queens Parade is looking deep red too.

The difference from the no tunnel case is that this will all be local bound traffic.  It won’t just clog up the Parade, but local streets and car parks as well.

The project will free capacity on Alexandra Parade that will be re-appropriated by motorists who will discover a a convenient route into the city and northern suburbs.

The differences predicted  in actual traffic volumes are not shown in the main CIS report, but only appear in the technical appendix.

 Traffic Volume Change with and without EWL- VLC tech report


This map shows blue lines where the model thinks traffic would be less-worse in 2031 if the tunnel were built than if not.

Red lines show where they admit the tunnel actually makes things worse – by inducing traffic.

Even for the blue lines, there is still an increase on today’s traffic, which is built in by the current transport and population policies of the two major parties.

The figure shows a large and predictable increase in rat-running in Clifton Hill west of Hoddle Street.

The tunnel will also bring more grief to Chandler highway.

The tunnel will merely shift congestion from the central corridor to its edges.

The blue lines can be explained by the tunnel attracting traffic of adjacent routes.

Daniel Bowen from the PTUA looked at the same congestion busting claims made to justify CityLink. He concludes  “The result is that while there are some time savings, they are nowhere near what was promised. The travel times in AM peak today in most cases are actually closer to the pre-motorway times than the promised times.”

See also:

East-west link to hit peak capacity by 2031-expert

And the expert’s ‘clarification’ : Traffic expert says claims peak hour east-west link traffic would be reduced to 30kmh in 2031 are incorrect

There is no modelling for after this date.

4 thoughts on “Do these forecasts make any sense?”

  1. Terry Croft says:

    I would like to take issue with you that figure 7-16 shows an increase of 20% -50% in traffic along Alexandra Pde. This drawing does not show change it merely states what the volume to capacity will be in 2031. To determine the change you need the current V/C plot which is not in the CIS.

    A far more useful diagram is figure 7-17 which gives the volume change between existing and that projected for 2031 without EWL. This is a 5%-10% increase. Figure 7-20 shows the effect when EWL is taken into account. This figure indicates a 10%-20% decrease. Thus the overall effect is around a 5%-10% decrease along Alexandra Pde with a tolled EWL in 2031.

    The big flaw in this modelling is not enough allowance is made for aversion to tolling which in turn means more will use Alexandra Pde. Also is the modelling as accurate as VLC maintains? Doug Harley, the former head of Vicroads modelling doesn’t believe so.

  2. Jim says:

    So after 15 billion dollars are spent and we’ve suffered years of disruption, the E-W will deliver a few minutes time savings to drivers. Wow.

    The Americans have a word for describing huge projects like this that are designed to enrich their builders, financiers and consultants but deliver substandard benefits, boondoggle.

  3. Jim says:

    Here’s a 2008 Boston Globe story on a notorious road tunnel boondoggle in Boston known colloquially as the “The Big Dig”. The article is about how the completed 22 billion dollar Big Dig has simply shifted the bottlenecks.

  4. Nick Bishop (318) says:

    Sometimes these diagrams are used for the wrong purpose (usually by the LMA).

    In Michael Veitch’s response to public submissions (report), he rebuffed the community claim that the tunnel will simply shift congestion from the inner east to the inner west … by presenting the Demon Diagram (Fig 18).

    But that diagram does not measure congestion, nor does it include the actual project (tunnel/viaduct where the congestion will be shifted to). If I was answering that, I’d produce a diagram showing the speed of vehicles, ranging from dark red (5km/h) to bright green (at the speed limit), and include the project.

    Wrong diagram, wrong purpose.

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