A proposal for method to assess alternatives of proposed road investment in a planning phase

Abstract

The subject matter of this research paper is an efficient assessment of the routing options of planned road investments in the planning phase. A simplified method is presented which, in the authors' opinion, combines reliability with relative simplicity and with a small input of labour needed, which factors make it suitable for use in very early stages of the process of engineering. The proposed method assesses the usefulness of the road, safety of traffic and its environmental impact. The measure of usefulness of the planned route is congestion relief on the existing road network and shortening the time of travel in relation to the zero option (without investment). The traffic safety analysis considers the effect of the route geometry and location of interchanges (in the case of expressways and motorways) on the probability of road incidents. The environmental impacts of the project considered in this research include its effect on the vehicle exhaust emissions and the associated clearing of forests and habitat fragmentation. The assessment was carried out by scoring. The above-mentioned criteria were combined in the final assessment by the objective function, taking into account the routing effectiveness and the estimated cost of the investment. The application of the method is presented on the basis of different options of linking expressway S3 with the A4 motorway in the Wroclaw-Bolkow corridor.