Road sector investment need assessment through traffic demand forecast

Abstract

Transport demand in Bangladesh has grown faster than the GDP growth of the country. Transportation improvements contribute to economic development of a country. Bangladesh has developed an extensive road infrastructure at the cost of millions of dollars borrowed from development partners. Lack of policy strategy, inadequate planning and biased regional focus create investment inefficiency in transport sector of Bangladesh. During the last couple of decades transportation attracted more than twenty percent of national investment - most of which is concentrated in road sector. Hence, there exists a scope to analyse the transport network improvement requirements and investment need in the country. This study develops a methodological framework to assess the future traffic demand in Bangladesh and analyse the transportation investment need. For the purpose of analyzing future transportation investment needs in Bangladesh a model has been developed. The overall structure of the model developed in the study is traditional in terms of the sequence of the structural form i.e. Trip Generation and Attraction, Trip Distribution, Modal Split and then Trip Assignment stages. In the context of Bangladesh, the data for the 20 greater districts or region is analysed. Mainly interzonal major roads are considered as network in this study. Road network is developed in SATURN as well as in TransCAD. Population and GDP data are used for Trip Generation and attraction Model. Gravity model is used for Trip Distribution and Multimode Logit Model used for Modal split. From the forecasted data future traffic in road network is assessed. Analysis of future traffic has been done for the years 2015 and 2025.The impact of traffic on existing network has suggested some improvement of road network. Among numerous options some options have been analyzed to see the treated network condition. In the study, it is observed that network traffic flow condition can be improved by taking necessary measures. Four laning of major roads; rail service improvement; upgrading of road condition by improving road geometry; construction of Dhaka-Chittagang expressway are some measures that have been taken as the improvement treatment of the network to carry future traffic. It is found that travel time can be saved 44.7% (year 2015) bY-making major roads four lane. Railway improvement will save 62.75% of travel time of the road passengers. In this study it has also seen that construction of expressway from Dhaka to Chittagang will not only be useful for the particular road but it will also have a positive impact to the entire network. This study is made to develop a tool to view of the future transportation network scenario and to realize the need for investment in this sector.