Myth: Spending more money on roads makes us safer

Myth: Spending more money on roads makes us safer
Fact: Spending more money on roads encourages more trips to be made by car and fewer by public transport, walking or cycling. Increased traffic volumes mean more crashes, regardless of how big the roads are.

A variation on the freeways-are-safer argument says that widening of arterial roads can be justified solely on safety grounds. This particular myth is sighted frequently during election campaigns, such as this example from the 2004 Federal election:

Traffic research from all over the world points to the fact that dual carriageways greatly increase the safety factor of roads. When are we going to wake up to the realisation that this is not about becoming more informed? It’s about making decisions to spend money on our roads that will save lives.

—Andrew Evans MLC, for the Family First Party

The RACV naturally likes this argument too, and trots it out regularly.

There is not a widespread or deeply held public understanding of the safety benefits of road investment….There is a challenge for all of us in 2005 in convincing all levels of Government that committing money to roads should be seen as an investment that will ultimately save government money. Better roads mean safer roads and as such less trauma and less pressure on the hospital system.

—RACV President Clive Hall in RoyalAuto, February 2005

The RACV’s latest initiative is its ‘five-star safety rating’ system for country highways, complete with a map showing the ‘safe’ roads in green and the ‘unsafe’ ones in red. It’s easy to get the mistaken impression that these ratings reflect actual crash statistics. The way they’re actually assigned is by road engineers looking at the road and counting up the features they deem to be ‘safe’ (such as dual carriageways and nice wide lanes) or ‘unsafe’ (such as trees by the road, or roads that cross on the level rather than with freeway-style interchanges). Roads can be assigned a ‘dangerous’ one or two-star rating even if they’ve recorded no crashes for years.

All this is just the road lobby up to its same old tricks: taking legitimate community concerns about road trauma, and manipulating them into a campaign to build more roads. It’s no doubt very convenient that the biggest, widest roads – the sort that invite high levels of induced traffic – are automatically judged the ‘safest’ by the RACV’s criteria. Yet it’s also true that the ‘safest’ roads in their survey are also the ones (such as the Hume Highway) that tend to record the highest crash rates – the common factor being that these are the ones that carry the highest volumes of traffic (and have consequently attracted the most spending).

This is what makes nonsense of the road lobby’s basic premise. Widening a road, or converting it from single to dual carriageway, has the primary effect of increasing the volume of traffic on the road. People take advantage of the superior level of service offered by the new road to drive on it further and more often, or are forced to when the new road is used as an excuse to close down local services. Meanwhile, the single greatest factor determining the level of road trauma is the volume of traffic – as more and more cars use a road more and more often, there is more opportunity for crashes, even if all the cars are travelling in the same direction.

Then there is the phenomenon of ‘risk compensation’, noted by many safety researchers, where drivers react to improved roads by driving faster and with less care. Thus, one finds that Victoria’s three worst black spots are all on dual-carriageway roads. This fact is not lost on RACV members:

I have been an RACV member for many years and appreciate the roadside service, especially since moving to rural Victoria….[I do not] agree that improving the road system will reduce accidents. We have few accidents but we do have far too many crashes. Crashes are mostly caused by people. Alcohol is not a cause; it is the person who drives after drinking who is the cause of a crash. Bad roads are not a cause; it is the person who cannot allow for road/traffic conditions.

—John Hensler (Tesbury), RoyalAuto, March 2006

Sadly, the tragic sixfold fatality in Mildura in February 2006 (involving people who weren’t even on the road at the time) shows that the most horrific incidents can occur even on perfectly straight roads with little traffic and no evident hazards. Dual carriageways are no panacea either, as shown by a litany of tragic crashes: a fivefold fatality on the Bass Highway in Tasmania in February 2006, a smash on the ‘four-star’ Hume Freeway at Glenrowan that killed three people just before Christmas in 2007, the fivefold fatality on Plenty Road in Melbourne in January 2010, and a threefold fatality on the Hume Freeway at Menangle south of Sydney in January 2012.

It’s surprising how much cars get up to, they run out of control, strike trees and poles, and are involved in accidents, often with seemingly minimal involvement on the part of their owners.

—Duncan Bourne, Sydney commuter

Heightened risk exposure goes hand in hand with greater traffic volumes, and is the major reason why Victoria’s road toll remained static – hovering around 400 deaths per year between 1992 and 2002 – despite a continuing rollout of new road safety measures (not to mention an unprecedented level of spending on new roads). While the risk of being fatally injured on the road – as measured by the number of fatalities per kilometre travelled – has indeed decreased, the increase in the number of kilometres travelled completely cancelled it out, so the actual number of fatalities per year was no less in 2002 than ten years earlier.

The stand-out record for the biggest decline in the road toll is still held by the years just prior to 1992, coinciding with the introduction of automatic speed cameras and higher rates of random breath testing. (It was also a time when public transport briefly increased its share of travel at the expense of the car.)

Year Victorian road fatalities
1990 548
1991 503
1992 396
1993 435
1994 377
1995 418
1996 417
1997 377
1998 390
1999 384
2000 407
2001 444
2002 397

Source: Transport Accident Commission (

Subsequent movements in the road toll tell a similar story. In 2003, there was a small but sustained drop of about 15%, from an average of 400 to an average of about 340. But there was no downward trend – rather there seems to have been a one-off change between 2002 and 2003, most likely resulting from something that changed in 2002. This was not a big year for new roads (CityLink had opened a full three years earlier, and the Hallam Bypass was still under construction). On the other hand, the controversial reduction in the speed limit tolerance from 10 per cent to 3kph, and the TAC’s ‘Wipe Off 5’ campaign, both commenced in 2002. Road safety researchers generally consider this to have caused the one-off drop in the road toll. Once again, the evidence indicates it is stricter enforcement rather than new roads that makes us safer.

Year Victorian road fatalities
2003 330
2004 343
2005 346
2006 337
2007 332

A further ‘step change’ in the road toll occurred in 2008: again by 15%, from 340 to around 300. There was one motorway opened around this time (Eastlink in June 2008) but this really came too late to be a convincing explanation for the drop. Meanwhile, official statistics indicate that between 2006-07 and 2007-08 there was a slight dip in overall car travel, defying the steady year-on-year growth seen until the mid-2000s. Melbourne’s overall level of car travel has been static ever since, neither increasing nor decreasing very much. So a reduction in car travel, and corresponding shift to public transport, is likely to be at least a contributing factor.

Year Victorian road fatalities
2008 303
2009 290
2010 288
2011 287

The statistics for serious (non-fatal) injuries tell a similar story. TAC figures show that the number of serious injuries (as measured by the number of TAC claims involving hospital admission within 7 days of an incident) has hovered between 5,200 and 6,100 per year since the turn of the century. Compared with the 25% drop seen in the road toll over the past decade, any downward trend in the ‘hidden road toll’ of serious injuries is very slight: at most 10% over the same period. It is therefore likely that the reduction in fatality rates owes just as much to the medical profession’s increasing success at keeping crash victims alive as it does to actual road safety improvements.

Nonetheless, road lobby spin-doctoring about bigger roads being safer roads can sometimes receive what sounds like more official backing. Throughout the previous decade, road lobbyists relied heavily on this statement from the 2000 National Road Safety Strategy:

Improving the safety of roads is the single most significant achievable factor in reducing road trauma. Further investment in safer roads is highly justified on both social and economic grounds. Road investment improves road safety through general road improvements – typically, ‘new’ roads are safer than ‘old’ roads – as well as through treatment of black spots.

— National Road Safety Strategy (2001-2010), page 6

This claim that spending money on new roads is the ‘single most significant’ safety measure came from a pie chart in the Appendix (page 29 of the same document) which postulated that road-building would reduce expected casualties by 19 per cent, compared with 10 per cent by improving vehicle occupant protection and 9 per cent by improving road user behaviour. Yet if one looked for the source of these figures, one found the following:

(10) Australian Transport Safety Bureau calculation drawing on P. Vulcan & B. Corben, Options for a National Road safety Strategy: Report to the National Road Transport Commission, (unpublished), 1999.

In other words, the basis for this seemingly authoritative assertion was an undocumented calculation based on an unpublished report by two road engineers. This is the case in general: rarely does any such claim (offical or not) actually cite published figures in support. They rely instead on the principle of truth by repetition: say something often enough and loud enough and people will come to believe it.

When one actually does look at published figures on the factors that reduce road trauma, they tend to support a quite different conclusion. The biggest reductions come from measures that focus on driver behaviour (such as speed cameras and booze buses), with smaller reductions coming from road works (such as blackspot treatments). The figures also confirm that a large factor in road trauma is the volume of traffic, which in a car-dependent society like Australia closely follows the level of overall economic activity.

Percentage Reductions in Victorian Road Trauma from
Specific Factors
Factor 1990 1991 1992 1993 1994 1995 1996
10-11 10-11 10-11 10-11 10-11 10-11 10-11
5-7 5-7 5-7 5-7 5-7 5-7 5-7
Breath testing
& adverts
9-10 9-10 9-10 9-10 9-10 9-10 9-10
alcohol sales
3 6 7 9 8 9 10
2 12 15 16 14 10 10
Black Spot
1.6 2.5 3.2 5.3 6.2 6.2 5.6

Source: Monash University Accident Research Centre. Further modelling of some major factors influencing road trauma trends in Victoria: 1990-96, Report No.129, 1998.

According to news reports, Monash University researcher Bruce Corben now takes the view – based on the evidence – that road safety is best promoted by measures that target road user behaviour. One such measure is reduced speed limits.

Cutting speed limits across the board by 10km/h could reduce deaths by as much as a third, said Dr Bruce Corben…. Even though we’ve managed to drop the annual toll by one or two a year, we really can’t claim we’re making great strides, Dr Corben said yesterday.

Dr Corben said Victoria had lost its place as one of the top two or three road safety leaders of the world, replaced by Sweden, the Netherlands and Britain, all of which had generally lower speed limits, particularly in urban or built-up areas.

Reduce speed limit to cut toll: road trauma expert, The Age, 1 January 2012

Medical professionals also study the causes of road trauma, just as they study the causes and spread of disease epidemics. Here too we find the view that driver behaviour, and not the size of the roads, should be the focus.

Overall….there is nothing wrong with the modern car. Nor is there anything very wrong with our roads. Despite the criticisms, we have relatively safe roads…. Rather, it is the lack of preparation for the journey and the aggressive, irrational, often non-thinking behaviour that all too often characterises the driver. Put simply, our road toll is high because we are not using our brains.

—Emeritus Professor Roger Rees, Flinders University School of Medicine, in The Age, 22 April 2006

But perhaps the last word should go to the police, who have seen more than enough crashes to understand the causes.

The best infrastructure in the world, the most innovative approach to road safety in the world, won’t cater for drivers who take a risk. There is a cultural change which needs to occur. It means drivers should not take the roads for granted…. The roads are as good as those who use them.

—Assistant Commissioner for Traffic, Victoria Police, in The Age, 25 June 2007

Just as building more roads doesn’t solve traffic congestion, it doesn’t make our cities any safer either, and for the same reason – it just encourages more and more car trips and fewer public transport, walking and cycling trips, which are less risky on the whole.

Last modified: 18 June 2012