Cross-border spatial data harmonisation for a flood early warning system at the lake Constance

European initiatives like the European Water Framework (WFD) Directive and the Infrastructure for Spatial Information in the European Community (INSPIRE) Directive are dealing with cross-border issues. One of the best known examples of hazards that adhere strongly with cross-border aspects are floods, since water doesn"t stop at borders. In a cross-border flood situation, heterogeneous data which are necessary for a GIS-based visualisation and analysis of flood areas in the affected countries cannot be manually integrated at each command and control centre. A common data model based on European-wide standards is therefore required which was developed for the scenario European Risk Atlas (ERiskA) in an EU funded project HUMBOLDT. HUMBOLDT, which has started in 2006 and was completed in March 2011, has the aim to contribute to important parts of the implementation process of a European SDI. In this sense, ERiskA aims at facilitating cross-border cooperation between the agencies responsible for disaster management in the Lake Constance Region that covers Swiss, Austrian and German territories. A prototypical add-on to a disaster management system was developed to facilitate exchange of information on potentially flooded areas and inundation of infrastructure like roads and railways. In this context, a number of interoperability and data harmonisation issues were addressed within this scenario. This paper represents 4 years of experience and results of ERiskA in the field of flood information.