BUSINESS INTELLIGENCE and the butt of numerous disparaging remarks and commentary . The reality is that SANRAL saw the e-toll system as the solution to funding the very real need for road infrastructure , in an easy and efficient way . But before we discuss this , we need to have a little background as to why we even need money for roads , given the burden the taxpayer has in supporting a top-heavy government and a seething mass of poor .
Why maintenance ?
While South Africa ’ s roads can compare favourably with any developed country you would care to name , they require maintenance , more so after heavy rains when the infamous potholes appear in our city and suburban streets . And therein lies the crunch . Of the 750 000km of South African roads , only a mere 22 000km fall under SANRAL ’ s responsibilities , and these are not those potholed roads in front of your house in downtown suburbia . The authority ’ s mandate is national roads . Yet , this argument has been the cause célèbre for the e-Tag dodgers , citing poor urban road maintenance as an example of villain SANRAL ’ s perceived negligence . Louw Kannemeyer , SANRAL ’ s new engineering executive , appointed in November 2017 , is impassioned when he speaks about this perception . He explains : “ If you go back into the history of SANRAL , you will see that we have what we call preventative maintenance . On a frequent cycle , we are trying to maintain the network [ of roads ] through periodic actions that keep the surface of the road waterproof . We are attempting to prevent the rapid deterioration of the national road network .” Kannemeyer explains that South African roads have a specific design to achieve the necessary waterproofing : “ The design of roads in South Africa is based on having a very thin waterproofing membrane at the surface .” Compared to Europe and the US , where this membrane averages about 100mm or more of waterproofing layer , South Africa has between 10 and 40mm . The engineer explains that this is largely because we are not an oil-producing country and that layer of waterproofing uses ( imported ) bitumen — a black viscous mixture of hydrocarbons obtained naturally or as a residue from petroleum distillation . Cost is an issue . He explains that over time , and for about the past 40 years , “ the bitumen layers have been substituted with good quality , natural gravel materials ” to counter importing costs . Kannemeyer adds that this substitution has managed to reduce initial road construction outlay by between 30 and 50 %, depending on the location . He goes on to elaborate that , because the waterproofing layer is so thin ( compared to overseas ), when that layer cracks , water ingress occurs , undermining the granular layers beneath the tar , which soften and collapse , resulting in potholes if not repaired timeously . He emphasises that this is the reason that preventative maintenance is so crucial in South Africa . So , what is causing the extensive road damage ?
Rail vs road freight
In South Africa , economic growth and the change to ‘ just in time ’ manufacturing and limited warehousing , results in the need for smaller more frequent deliveries , which favour road transport above rail . Since deregulation in 1988 , the modal split has changed to road ( 87 %) and rail ( 13 %). The result is an increased number of heavy vehicle axles on roads , and since road pavements are designed for the number of heavy vehicle axles over , the lifespan ( in years ) decreases . According to Kannemeyer , the conception that our roads are damaged by heavy trucks hauling freight , as a result of poor or absent rail infrastructure , is not necessarily accurate . He comments : “ Worldwide , road freight patterns are the same , in terms of rail versus road ,” he says . It is not peculiar that we use our roads so extensively for freight ,
Kannemeyer assures , as the worldwide trend is to focus on cost efficiency : “ The ability to move your container on its own , receiving it on time , is quicker than loading it onto a slowmoving train . Even in Europe there are similar patterns — in fact , worse than ours . They have a 90 % road and 10 % rail ratio .” It is often remarked that our roads are not built for heavy loads , for transporting ore from the mines and timber from plantations , for example . Kannemeyer counters this observation : “ We don ’ t design a road to last a certain number of calendar years . We design it for the traffic that we expect to move along the road during a specific number of calendar years ,” he emphasises . He explains that when a road is built , the present amount of traffic along that stretch is considered , both heavy and light , and it is forecast how this will change over a given number of years , for example 20 years . From this , a number is calculated . “ In South Africa , for the pavement design , that number is called the equivalent standard axle : the equivalent number of standard axles that are expected to use that road during its lifespan . That could number in the millions , depending on how busy the road is ,” he adds . “ That determines the kind of road pavement that needs to be constructed , to carry that traffic .” Kannemeyer explains that the preventative maintenance strategy works on an eight- to 12-year cycle . “ Every year , and at a maximum of two years , we assess the condition of our entire road network , in our two survey vehicles , equipped with 3-D cameras and lasers .” These cameras can detect a crack less than 1mm in width , while the vehicle travels between 80 and 100km / h over a distance of up to 600km per day , depending on travel and road conditions . That information assists SANRAL to monitor the progress of the development of cracks and optimise time maintenance intervention on the relevant road , which , he assures , takes place within 48 hours of an issue being detected . If a road has been designed with
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