Traffic projections: What do all the numbers mean?

At the East West Link public hearings this week there were countless numbers thrown around, with claim and counter claim about what they mean.

Transport Minister, Terry Mulder sounded justifiably peeved when he said,”it seems the commentary on this project is that either no one will use it or too many vehicles will use it”.

So what can we make of all the numbers?

Firstly, we need to understand there are five separate issues being discussed. And we are talking about four different measures – the traffic numbers today, traffic in 2021 when the tunnel opens, the traffic in 2031 after 10 years and what it would have been in 2031 if the freeway tunnel had not been built.

Here are the five issues:

1. There will be a big increase in traffic on the eastern freeway if the EWL is built
The LMA openly state that traffic on the eastern freeway will increase 50% from 135,000 vehicles per day (vpd) today to 200,000 vpd in 2031. There will be an extra lane each way added – but this is not being counted as part of this project. This is close to the capacity of the freeway and it will be severely congested (level of service D) in peak periods which LMA’s own expert, Michael Veitch, said equated to crawling speeds of 20-30 kph.

2. Traffic turning into Hoddle St from eastern freeway will initially drop, then increase 
Most of the traffic on the eastern freeway is headed to the CBD or inner northern suburbs and either turns into Hoddle or continues down Alexandra Pde. The tunnel would remove some of this traffic in the short term, but the rapid growth in use quickly wipes out this advantage. The LMA say it will be less in 2031 than if the tunnel is not built – but this is not saying it is less than it is today.

An aside: Hoddle St would be the main beneficiary of a public transport upgrade – the state government has announced $47 m for DART and a Hoddle St bus lane but you would have to spend three times that amount to make a serious dent in traffic volumes or go the next step of building a light or heavy rail line.

3. The traffic along Alexandra Pde  will be somewhat worse
The government has made claims of a big reduction in traffic turning it into a “boulevard” giving big time savings to cars and trams on North South routes. The evidence in  Document 44 (tabled this week) showed this up as a fiction. Actual current traffic is 62,000 near Hoddle St and 68,000 near Nicholson St. The GHD projections start from the wrong base (80,000 between Nicholson and Brunswick Sts includes Queens Pde traffic). The claims a small reduction to 76,000 vpd is actually an increase on current levels. It will be worse than current conditions. Trams will not make a saving in crossing Alexandra Pde and the “boulevard atmosphere” will be pretty much what you currently see.

4.  Traffic in the tunnel will reach capacity by 2031
The government has always said the tunnel would take 80-100,000 vpd, but unlike the other numbers this is for soon after opening.  By 2031, traffic will have built to 120,000 vpd which will be pretty much at capacity in the peak. The LMA traffic experts conceded a peak hour level of service D which is what one sees in the Burnley tunnel – slow moving traffic in peak times.  The fact the tunnel reaches capacity doesn’t mean it will be a financial success as even a high toll will only recover about a third of the project cost. The LMA has clearly flagged that the EWL will operate with peak tolls higher than currently apply on other toll roads in Melbourne.

5. The Flemington viaduct (Part B) will be underused without a further western connection
Most of the tunnel traffic is actually heading north along CityLink with Melbourne Airport the overwhelmingly dominant destination. Southbound traffic is predicted to split 50/50 between CityLink (heading for Westgate) and the new Part B leading to the port. This will only attract 10,000 vpd which amounts to 300 cars per lane at peak hour a pretty empty road. The City of Melbourne has been making a strong case that this section is not needed – at least for the first decade.  However, when WestLink is built to Sunshine, the traffic on Part B is projected to increase to 60,000 vpd as traffic flows in from the western Ring Road. The unanswered question is how this later boost in traffic will be accommodated given the East West Link tunnel will already be at capacity.

6. Local streets will see little change
The LMA have spent a long time on their (red and blue) Demon Diagram which purports to show big decreases on all inner suburban streets and increases mainly on the freeways. However this is misleading as again it compares 2031 with and without the tunnel and not the comparison to now. Most residents will see pretty similar conditions to now in their street.  The big exception is Moonee Ponds, including Travancore, which will get a big influx from the Ormond Rd ramp and several streets in Parkville and North Melbourne that lead to the Elliot Ave access to the tunnel.

The fundamental problem is that the tunnel will attract a big increase in traffic on the freeway and this will flood into the inner city. Chris Wren QC likened the freeway to a drain – the bigger you build them the more they fill up.

The LMA expert Michael Veitch rejected the idea that freeways induce more traffic – although he conceded they attract traffic from other routes and encourage longer journeys. This argument will be tested when the City of Yarra call their traffic specialist Michelle Zeibots in two weeks time.

By Andrew Herington