Interdependencies among Critical Infrastructures (CIs) are the basis for domino effects that may have serious consequences for society. Especially in urban areas, the high density of these infrastructures and their geographic proximity may result in failures due to geographic interdependencies, one of the four types of interdependencies that exist among CIs. Studying the issue of geographic interdependencies raises a specific problem that must be addressed. Such a study necessarily requires information on the location of system infrastructures in order to determine their proximity. Access to this kind of information is one of the major difficulties associated with the study of geographic interdependencies. Because this kind of information is confidential, systems are not willing to share it. This article presents an approach that makes it possible to study geographic interdependencies among CIs but requires only a minimum of information on the specific location of system infrastructures. Based on the concept of so-called flexible cartography, this approach provides relevant results for the processing of interdependencies, while respecting organisations' confidentiality constraints.
Keywords: critical infrastructures, geographic interdependencies, confidentiality, protective measures, preventive measures, warning mechanisms, domino effect, system infrastructures, flexible cartography