The creation and application of a national freight flow model for South Africa

South Africa suffered from a historical lack of freight-flow information that was detrimental to infrastructure planning, optimal network development and market structuring. This paper proposes a methodology that can fill this gap, be repeated annually and is, by its nature, not prone to the errors of market surveys. The methodology develops a comprehensive description of South Africa's surface freight flow market space based on the definition of four definitive freight flow market segments. The results from the annual South African National Roads Agency (SANRAL) traffic counts are allocated to these segments to develop national road freight flows. For rail freight flows, the rail database is reclassified on a station-to-station (i.e. origin-destination) basis to match the freight flow market segments developed. Consequently, modal flows, market share and total flows for all freight flow market segments and the geographical groupings with the segments can be analysed and reported each year. The results confirm the deteriorating role of South Africa's rail system amidst growing freight demand, as well as the concomitant over-cropping of the road network, and therefore enable the development of specific national freight transport policy recommendations.