SMALL SCALE TRANSPORT MODELLING: THE CASE OF A ROAD THROUGH SERENGETI NATIONAL PARK IN TANZANIA
María Díez Gutiérrez, Norwegian University of Science and Technology, Trude Tørset, Norwegian University of Science and Technology, Eirik Skjetne, Norwegian Public Roads Administration
This paper aims to defend the use of simple transport models in uncomplicated transport networks as a tool in the decision making process. Our case study is a road through the Serengeti National Park in Tanzania.
Transport modelling is becoming more sophisticated due to the increasing transportation needs in urban areas. Nonetheless, less complex situations, refer in this case to low density roads in simple transportation networks, might be just as useful input to decision making processes as advanced transport models.
This paper pursues to defend the use of simple transport models for non-complicated but still difficult decisions related to infrastructure projects. The Serengeti National Park is used as a case study. Tanzanian government is considering building a road through the Park to connect the western and northwestern parts of the country. Some alternatives to the existing road alignment have been suggested, and many local, national and international parties have strong interests in specific solutions. The decision must thus balance between preserving, economic development, social and health, and environmental issues. A simple transport model is designed and applied to shed light of the demand, both current and in the future.
We model the current traffic volumes in the Park based on traffic counts registered at gates when vehicles enter the Park and at airport terminals when visitors arrive by planes inside the Park. The future traffic is estimated following the actual growing trends for tourists and locals. We further account for the transport diversity, namely: (1) tourist transport to/from the Park, (2) tourist transport through the Park, (3) Tanzanian transport to/from the Park, (4) Tanzanian transport through the Park, (5) heavy vehicles transport to/from the Park, and (6) heavy vehicle transport through the Park. We model different network scenarios by using the current road network as the "do-nothing" scenario and adding two alternatives; a road improvement through the northern Serengeti and a new southern road outside the Park. In addition, we create a new scenario simulating the new international airport proposal in Mugumu.
The results show that the use of simple transport models are very useful for uncomplicated transport networks. Adding a little extra complexity to counts, we obtain a more transparent method and indications of the variation in the traffic volumes in the whole network for the different vehicle types. The impacts of new infrastructures can be partly addressed using simple transport models. Nonetheless, several tools should be combined to obtain a good overall assessment.
María Díez Gutiérrez, Norwegian University of Science and Technology.
Trude Tørset, Norwegian University of Science and Technology.
Eirik Skjetne, Norwegian Public Roads Administration.
James Odeck, Norwegian University of Science and Technology.
Eivin Røskaft, Norwegian University of Science and Technology.
Association for European Transport