Tıkanıklık fiyatlandırmasının İstanbul için uygunluğunun araştırılması: Eminönü fiyatlandırma modeli.

Congestion is one of the major problems of metropolitan cities. This problem arises when the increase in demand for travelling with private vehicles surpasses the capacity of the road network. Travel demand management strategies are developed to restrict the excessive demand without making expensive infrastructure investments. Demand management strategies can be classified in two main groups: Fiscal and non-fiscal strategies. Fiscal strategies are implemented to regulate the demand by arranging taxes or tariffs collected for the usage of the transportation infrastructure or facilities. Non-fiscal strategies aim to adjust the demand for private vehicle usage without imposing any financial measures on individuals. Congestion pricing is one of the most powerful fiscal strategies. By definition, congestion pricing is collecting fixed or variable amount of tolls from private vehicle users for the usage of a road or a road network. For variable toll implementations, the amount can be determined according to units such as distance covered or congestion level of the facility. Any driver considering entering a congested road will base his/her decision solely on the costs he/she is going to bear. However, entering an already congested road will impose external costs on other drivers currently on the road, as well. The last vehicle entering an already congested road will increase not only the travel times but also the fuel consumption and emissions of all other vehicles. In the case when natural equilibrium occurs, although abovementioned costs already exist, none of the users are paying the price of creating them. In order to make the users pay the price of the external costs they create, marginal cost pricing is implemented. The price collected by marginal cost pricing implementations is named the optimum price and its value is equal to the external costs that users create. Congestion pricing can be modelled by using two different modelling approaches: Timeindependent static models and time-dependent dynamic models. Time-independent static models deliberately ignore the hourly changes in the traffic parameters and accept an unchanged relationship between parameters of traffic throughout the analysis. On the contrary, time-dependent dynamic models include the time dimension to the analysis and model the implementation with regard to departure time, as well as route choice. The origins of dynamic models is the bottleneck model which is originally developed by Nobel Prize winner researcher William Vickrey. In this study, a congestion pricing scheme is modelled for Eminonu, in order to evaluate the applicability of congestion pricing to Istanbul. Among all the districts of Istanbul, Eminonu have unique properties. First of all, the district which is a peninsula has clearly defined borders, easing the access control issues. Moreover, due to the small surface area of Eminonu, the road network is relatively small and less complicated. As the host of many historic, recreational and governmental areas, severe congestion is routinely experienced on the road network of the district. The focal point of the modelling studies for Eminonu is the determination of optimum price which is calculated according to the principles of the static models of congestion pricing. Analysis of the equilibrium conditions is made possible by obtaining, average cost, marginal cost and demand curves representing the whole district. In practice, marginal cost pricing may sometimes be ignored or not preferred to be implemented by decision makers. Thus, an evaluation of other pricing regimes different than optimum price is also included in the study. Furthermore, the gains, losses and related measurable economic quantities for the individuals are also calculated. The optimum price is calculated as 0.58 TL/km. It is expected to record a decrease close to 16% in the usage of private vehicles by collecting this toll. Maximum revenue can be generated by collecting a toll of 5.042 TL/km which reduces the number of private vehicle users more than 76%.Futhermore by deploying the average travelling distance of 5.32 km in Eminonu road network, per km prices can be converted into constant prices. Consequently, the optimum price is equal to 3.09 TL in constant values. This study provides valuable information for the applicability of congestion pricing to Istanbul. Obviously, when a congestion pricing scheme is introduced significant amount of individuals will start to travel without their private vehicles and considerable amount of money will be collected In order to secure sustainability and acceptability of the scheme, the revenue collected from the individuals must be returned to the system in favour of users who are worse-off by congestion pricing. [ABSTRACT FROM AUTHOR]