Methods in flood hazard and risk assessment

This technical note provides an overview for authorities who wish to conduct flood hazard and risk assessments and who must develop a step-by-step plan for carrying out the assessment that is appropriate and feasible in the local context. Floods are amongst the most frequent and destructive type of disaster, causing significant damage and disrupting livelihoods throughout the world. There is a wide range of flood risk management methods available that can reduce this destruction, and managing flood risks requires the estimation of flood hazards and the impacts that they can cause.

The goal of flood hazard assessment is to understand the probability that a flood of a particular intensity will occur over an extended period of time. It is important to keep in mind, however, that many aspects of flood hazard and risk assessment require specific expertise and experience. It is not advisable to conduct these assessments if your team lacks this experience, and this technical note does not provide specific guidelines, which can vary dramatically depending on local and regional conditions.