Technology assisting traffic flow at toll plazas

13th October 2016 By: Anine Kilian - Contributing Editor Online

Combating traffic congestion at toll plazas is becoming a problem of the past owing to the evolution of Electronic Toll Collection (ETC), which has introduced new ways for motorists to pass through tolls without delay.

The South African National Roads Agency Limited (Sanral) noted in a statement on Thursday that, previously, it was normal for drivers to stop at a toll booth, make a cash or credit card payment and then wait for the boom to be raised before proceeding. However, with the new ETC, this has changed.
 
Bakwena Platinum Corridor Concessionaire, which is one of the concessionaires of Sanral, has been embracing ETC since 2002 and went one step further by introducing electronic movable barriers.

This technology makes it possible to increase the number of lanes at toll plazas to accommodate more vehicles during peak hours.
 
“The moveable barriers make it quicker and easier to reverse the lanes, which give capacity to move more traffic travelling in one direction during peak times,” noted Bakwena commercial manager Liam Clarke.

He explained that, if a plaza has 12 lanes, with six lanes per direction, the barriers could be moved to extend the lanes from six to eight for heavy traffic in one direction while reducing the six lanes in the opposite direction to four without interruption.
 
Bakwena is the first toll road to introduce the barriers in the country, starting at two of their plazas, Doornpoort and Pumulani.
 
“We had a capacity problem at Doornpoort, because we couldn’t move the barriers. We were unable to process the demand of 3 500 vehicles per hour, and were only managing 3 100,” he noted.

Clarke added that Bakwena would not have been able to change this if it didn’t have e-tags and the moveable barrier.
 
The operation of the barriers required training as the barrier had to move at a different speed over its length.

When one section moves 20 m, the other section has to move only 10 m to the point where it is required.

The barriers need to be heavy enough so that the wind does not affect them and vehicles stay in their correct lanes. However, they also need to be light enough to allow ease of movement.
 
Previously, the system took longer and required more people because the cones were picked up manually, whereas, with the electronic ones, the entire system is operated by one person, making it safer as there are fewer people moving around between passing vehicles.