Greens want induced traffic to be scrutinised

My understanding of the report is that is criticises the Vic Government for several faults, including the fact it does not consider the impact of induced traffic.

We have seen that sort of fault in the ACT with the failure to duplicate the GDE extension from the start, resulting in a relatively more costly exercise later.

Basically, the metrics used by engineers, project managers, designers, etc for transport are incorrect. As I stated, in certain circumstances this could mean we should change the metrics to ensure more lanes are built.

I believe in public transport, including light rail, although if all we take away from this is the need to improve public transport we are entirely missing the point of the auditor’s recommendations.

Don’t forget, induced traffic may well exist in a public transport scenario as well. We should challenge government on its claims of cars, passenger numbers, etc whether we are talking about roads or public transport.

I suggest the Greens have latched onto one aspect of the report for the benefit of public transport and not public administration in general.

I think if we take our political blinders off and look at what the Greens actually said you will find that its actually a quite sensible question to ask. Why do we accept the claims made that are used to justify building more roads?

The Majura Park Road upgrade will mainly benefit the trucks carrying freight from the Airport to the Federal Highway – that will be the reason it will receive federal government money.

These other claims regarding reduced congestion etc are just false. it caries 17,000 cars a day now, do you think that number will decrease when its changed to two lanes each way ?

Logic says it will not.

I am not saying you dont upgrade the road, because I have used it and it needs upgrading, but to thrust this road upgrade forward to Infrastructure Australia as the ACT’s PRIMARY infrastructure project is just bizarre – however totally instep with ACT Govt thinking.

Thr total cost of this road project will exceed what would be required to build light rail from Gungahlin to Civic. What do you think will deliver a greater long term benefit to ACT residents ?

Most of the commuters who fill the Majura Road from Gungahlin are commuting. Build a proper public transport system that would let them commute quickly, reliably and comfortably – and they will use it. This will reduce road congestion, and decrease the need to build more major roads.

Lets circle back to the report though. What I use when lobbying for public transport is evidence. Looking at claims made to justify all transport infrastructure investment is important, all claims should be scrutinised. maybe this sort of scrutiny would have delivered a properly funded GDE instead of a never ending construction zone which has caused more road congestion than it has ‘solved’.

Jim Jones said :

And, for the record, can I get this straight: You admit that you haven’t read the report or the release in question, but this isn’t important because “Learning has been one of my constant companions over many, many years”?

Perhaps you could let me know what institution you’ve attended, or book you’ve read, that suggests that ignorance on a topic doesn’t matter as long as you’ve spent lots of time at university?

I actually replied to this earlier but it was probably moderated – and quite rightly so in hindsight.

Your ‘for the record’ comment? Unless your writing my biography, what ‘record’ are you referring to?

My education level – and yours for that matter – is irrelevant to the issue. The Greens policy overall is one that I find generally distasteful due to the impacts it has or is required to have on us – a lot of it unnecessary I feel. There are people who subscribe to this site who are much better informed and qualified than me to comment on Greens issues specifically – and perhaps they are a bit better qualified overall that yourself as well – though that will be our little secret won’t it!

zippyzippy said :

Ok, so the report is pointing out that the Vic Govt ignored the fact that building the new road capacity makes it fill up with cars. I think the point is that government should look at other solutions like good public transport, not just build bigger and more roads expecting they will solve the problem. The lanes fill up with congestion – ie more capacity ‘induces’ more trips, more driving, longer trips etc. And even in the case that a Govt does decide to build a road with the view of solving congestion, it needs to accurately forecast the traffic, including the induced traffic. But this should also change their assessment of the benefits of the road – they’ll have to acknowledge that it will significantly increase greenhouse gas emissions, probably increase the number of accidents, increase the sprawl of the city, keep numbers away from public transport etc.

Has anyone done any numbers as to the volume of traffic that could be expected to be induced? No doubt there are a series of variables that would have to be considered, including things like the existing volume of traffic, the magnitude of the road improvement, access from new feeder areas, etc.

Surely a good solution would have to include both public and personal transport, with appropriate incentives to get people onto public transport while still providing utility for whom public transport is not viable.

zippyzippy said :

Ok, so the report is pointing out that the Vic Govt ignored the fact that building the new road capacity makes it fill up with cars. I think the point is that government should look at other solutions like good public transport, not just build bigger and more roads expecting they will solve the problem. The lanes fill up with congestion – ie more capacity ‘induces’ more trips, more driving, longer trips etc. And even in the case that a Govt does decide to build a road with the view of solving congestion, it needs to accurately forecast the traffic, including the induced traffic. But this should also change their assessment of the benefits of the road – they’ll have to acknowledge that it will significantly increase greenhouse gas emissions, probably increase the number of accidents, increase the sprawl of the city, keep numbers away from public transport etc.

What a pleasant change to have some informed thinking based on intelligent analyses of the actual sources.

Thank you.

Ok, so the report is pointing out that the Vic Govt ignored the fact that building the new road capacity makes it fill up with cars. I think the point is that government should look at other solutions like good public transport, not just build bigger and more roads expecting they will solve the problem. The lanes fill up with congestion – ie more capacity ‘induces’ more trips, more driving, longer trips etc. And even in the case that a Govt does decide to build a road with the view of solving congestion, it needs to accurately forecast the traffic, including the induced traffic. But this should also change their assessment of the benefits of the road – they’ll have to acknowledge that it will significantly increase greenhouse gas emissions, probably increase the number of accidents, increase the sprawl of the city, keep numbers away from public transport etc.

PM said :

Not sure what the Greens are wanting here.

Money diverted from new roads to improving public transport, at a guess, as building new roads to relieve congestion is a Sisyphean task.

PM said :

Figure 2B, Examples of induced traffic:

“M25 orbital motorway?London
The M25 was opened in 1986 with three lanes in each direction. The government expected
it to carry long-distance traffic wanting to bypass London and local suburban traffic for the
rest of the twentieth century.
However, it was filled to capacity for parts of the morning and afternoon peaks soon after it
opened…………….. ……………………
The consequences are serious. The decision to fund these schemes was based on an
assumption that they would give sufficient capacity for the next 20 to 25 years. By 2010 this
capacity had been used up.”

So there’s an argument governments should build more lanes upfront.

Not sure what the Greens are wanting here.

Sadly, the ACT Govt doesn’t need to read this report to understand this. They have their very own real-world example sitting in the middle of Canberra right now, currenly being expanded!

However, I think it was Ben Elton that said in his book Gridlock that ‘no traffic problem was ever remedied by building more roads’? Take for example the mention of adding an extra lane on Parkes way into the city (before the Orange tunnel). While this would stop the traffic jams under Black Mountain, it would simply deliver more cars, quicker, into the peak time gridlock closer to the city (on the other side of the Orange tunnel).
Where there are a lot of cars travelling to one endpoint (Civic) at one time, there is always going to be a delay when you hit the traffic lights and car parks at the destination end. Dumping more cars there faster won’t mean you get parked and into work that much quicker? Going home after work might be a different story though…

Figure 2B, Examples of induced traffic:

“M25 orbital motorway?London
The M25 was opened in 1986 with three lanes in each direction. The government expected
it to carry long-distance traffic wanting to bypass London and local suburban traffic for the
rest of the twentieth century.
However, it was filled to capacity for parts of the morning and afternoon peaks soon after it
opened. The traffic forecasts significantly underestimated demand and it was clear that it
had to expand to avoid gridlock at peak periods. The forecasts failed to predict the volume
of trips for short, local travel and the impact it would have on land use development next to
the motorway.

Pakenham and Hallam bypasses?south-east Melbourne growth corridor
The Pakenham bypass opened in 2007 and the Hallam bypass in 2003. Both raised
capacity on the M1 motorway connecting suburbs in the south-east of Melbourne with the
Central Business District and Melbourne’s middle and inner suburbs.
The traffic forecasts were significant underestimates:
• over most of Pakenham Bypass’s length, daily traffic in 2010 exceeded the 2011
forecasts by over 50 per cent and was close to the volumes expected in 2031
• Hallam Bypass’s daily traffic in 2010 overshot the 2011 forecasts from 15 to 29 per cent
for different sections.
The consequences are serious. The decision to fund these schemes was based on an
assumption that they would give sufficient capacity for the next 20 to 25 years. By 2010 this
capacity had been used up.”

So there’s an argument governments should build more lanes upfront.

Not sure what the Greens are wanting here.

Here is the full report:

http://download.audit.vic.gov.au/files/20110601-Major-Roads.pdf

Here is a summary:

http://download.audit.vic.gov.au/files/20110601-Major-Roads.rtf

I’ve read both.

Recommendations:

“VicRoads should:
– assess the significance of induced traffic for all major road projects and take account of this when forecasting traffic and estimating the economic benefits
– include sufficient information in its business cases on the reliability of the traffic impacts and economic benefits
– apply minimum business case requirements when fast-tracking a major road project
– review the lessons from all major projects on a scale commensurate with the size and complexity of the project and the likely benefits of the review
– incorporate the adequate measurement of project outcomes in its project management processes.

Linking Melbourne Authority should:
– improve the quality assurance of the transport modelling and the calculation of the economic benefits
– improve the quality assurance applied in estimating and revising the public sector comparator cost
– better inform decision-makers about the sensitivity of the comparison of the PPP and public sector comparator costs to small changes in the PPP discount rate
– document a plan to measure outcomes as part of the project development.”

Re Induced Traffic:

Figure 2A – Induced traffic responses to a road improvement; The ways people and businesses could respond to a road improvement:

Changing route—drivers make the same journeys but use the improved route.
Changing destination—drivers decide to travel to more distant destinations because the
improvement makes the journey time acceptable.
Changing mode—public transport passengers switch to car because the improvement
makes road travel more attractive than rail.
Changing time of travel—drivers decide to travel in the commuting peak period because
the improvement reduces journey times to an acceptable level.
Making additional journeys—people are willing to make additional car journeys because
of the improvement.
Relocated trip—people and businesses relocate to take advantage of the improvement
and so make journeys that are new to the area.