Navigation on the Danube: limitations by low water levels and their impacts

This report contains two parts: The first part presents an overview on studies concerning the Danube, inland navigation or the impact of climate change on either of those. The second part gives a more detailed analysis of inland navigation on the Danube, partly based on studies presented in part one. Part two covers the current situation along the Danube by covering the topic of bottlenecks and other limitations for shipping along the Danube. Based on these observations, an estimation of the economic impacts of low water periods on inland navigation is made. As a last step, measures to reduce the impact of low water on inland navigations are presented. The report shows, that inland navigation still is an important transport mode, along the Danube as well as in other European regions. Especially in Romania, inland navigation still has a share of more than 20% and rising in total transport. However, inland navigation depends strongly on the good conditions of its infrastructure. These good conditions are limited mainly by two factors: first are the so called bottlenecks. Those are areas with sub-optimal shipping conditions e.g. due to solid rock formations in the river that lead to reduced water depths. The second factor is the weather (and, on a longer time scale, the climate) which, mostly depending on precipitation and evaporation, can lead to low water levels seasonally. In addition to these two natural factors, laws which regulate the maximum number of barges allowed and human built structures like locks limit the size of vessels as well as the speed they can travel. These limiting factors are identified and located in the first chapter of part two of this report, before the water depth needed by several ship sizes as well as the cargo fleet available along the Danube are presented. One of the targets of this report is to estimate the economic impact of low water periods. All the factors named above as well as the freight prices charged for connections along the Danube are used to reach this target in chapter II.4. To estimate the impact of low water periods on the freight prices, a method developed by Jonkeren et al. (2007) for the Rhine is transfered to the Danube. By transfering the Jonkeren et al. (2007) method, regression equations for several transport connections along the Danube are identified that give a first estimate for the connection of freight prices and water levels. With the help of these regression equations, an estimation of the total