Truck exclusion lanes: What does the evidence say?

For the past four years, heavy vehicles have been prohibited from using the right-hand lane of two sections of Melbourne’s freeway network: the Princes Freeway between Kororoit Creek Road and Avalon Road (39 km), and the Eastern Freeway between Springvale Road and Hoddle Street (18 km). According to VicRoads, these exclusion lanes are “aimed at improving safety and encouraging better road sharing, while also creating a more efficient driving environment.”

Many in the truck industry complained at the time that this was an ill-conceived knee-jerk decision by government, with apparently no evidential basis and the potential to adversely affect the heavy vehicle and road transport industries. Traffic modelling by VicRoads found that it would be inappropriate to introduce such exclusion lanes on the Monash Freeway, and there are no current plans to roll out further implementations.

“Many in the industry complained that this was an ill-conceived knee-jerk decision by government…”

VicRoads has said, however, that the existing Princes/Eastern exclusion lanes will be retained and that consideration will be given to adding them to the Western Ring Road once its upgrade is completed. Is this position based more on an independent evaluation of hard evidence or the results of a quoted survey of RACV car club members that found, not surprisingly, that 83% of respondents supported truck exclusion lanes?

The question that needs to be asked is, “What hard evidence will be relied upon when considering the future implementation of truck exclusion lanes?”

The anecdotal evidence is strongly against them. Any trip down the Princes Freeway highlights the shortcomings to even the casual observer. Since the roll-out of fixed speed cameras on that road, every car now travels at around 95-98 km/h, regardless of which lane it’s in. The inherent conservative error in car speedometers compounds the problem. Now think about the truck driver with an accurately calibrated speedometer who wants to travel at a true 100 km/h. They can’t overtake in the right-hand lane, so they have the choice of either sitting in the middle lane ‘tailgating’ the slow cars or overtaking dangerously in the left lane. It’s a sad thing to see such inefficiency in our transport system.

A proper research-style evidence-based evaluation of the performance of existing exclusion lanes is long overdue.