Every year approximately 50 people die in the Netherlands because of a car crash into water. Each year about 700-800 cars crash into water. It is expected that changes in road design contribute to the decrease of the number of car crashes into water. The Onderzoeksraad voor Veiligheid executed a study to get an overview of the problem “car crashes into water (further called: CCW) accidents”. This study contains some recommendations for improving the design of the roads. Besides these recommendations, there are several CROW reference books containing guidelines for designing roads and roadsides in a safe manner. In discussions with road authorities preceding this research, it turns out that in practice these recommendations and guidelines end in discussions and complaints. For this reason the Ministry of Transport, Public Works and Water Management asked the Centre for Transport and Navigation to produce in cooperation with road authorities an overview of the most cost effective measures for road design. The aim of this research is to come to an approach, in cooperation with road authorities, which possibly will lead to improvements in the design of roads in order to reduce the number of CCW accidents. To realise this objective, successively CCW accidents were analysed, a workshop with the local road authorities and emergency services has been organized, a method to trace risky locations has been created, favourable measures are recounted and the process for possible nationwide introduction has been described. It turns out that the available data about CCW accidents is inadequate to find similarities between different CCW accidents in regard to the design of roads. The data is lacking in clear layouts or manoeuvre diagrams and often the cause of the accident is not registered. Also the exact location of the accident is frequently not registered. With the current data about CCW accidents only something can be said about the basic characteristics of accidents. The most important conclusion from the analysis is that 90% of the CCW accidents are unilateral accidents. The favourable measures, which are formulated in this research are mainly focussed on minimizing the possibility that a car fall into the roadside. The other measures are focussed on minimizing the possibility that a car ends up into the water, and on minimizing the possibility occupants of the car for being seriously injured. Because there is no concentration of CCW accidents it is important to be able to trace the locations with a high possibility of CCW’s. To trace these risky locations the ‘risk index’ has been created. This method offers the road authorities a practical tool to find these locations. The risk index can be determined by means of a table of risks categorized in road, roadside, water and speed. By means of the risk index road authorities can decide to take measures. It has to be emphasized that the risk index has been created on the basis of the limited available knowledge. (Author/publisher)
Abstract