The flood fighting problem: A basic model and construction heuristics

Natural disasters such as floods occur more and more frequently due to climate change and claim many victims. If protective measures such as floodplains and dams are not sufficient or are damaged, emergency services must be deployed. In order to be able to deploy them as effectively as possible, we present a model for emergency services planning in the event of flooding. The mathematical model is based on the idea that the area of interest is subdivided into cells and snapshots of the situation are considered at discrete time periods. This way, we can model the spread of water over time taking the specific profile of the terrain into account. Also, the locations and the movement of the emergency teams can be described with user–specified granularity. Since solving such models optimally is out of the scope of today’s computational capabilities, we discuss several variants of so–called construction heuristics. Such methods run fast and produce results that help to assess a flood situation and about what can be achieved over time by fighting the floods. Such insights may not only help after the occurrence of an event, but also in advance in order to be prepared better. In a computational study the performance of heuristics based in simple priority rules is studied.