Flood defense is a problem of vital importance, for which knowledge and advanced scientific tools play a paramount important role in the strain of coping with flooding problems. In this context, flood model-ing represents the basis for effective flood mitigation measures. By using models, an attempt is made to replace trial-and-error-based strategies, as practiced in the past, with more physically based measures of flood management and control. Mathematical models are the best tools, nowadays available, for the design of efficient flood protection strategies and excellent supporters of decision-makers. With refer-ence to these issues, the paper provides a complete application of the procedures, nowadays available, for risk assessment, from catchment to a very local scale, on the Lambro River in Milano, Italy. It is shown that social and political constraints may force risk managers to find different solutions to solve the problems they have to face, which may be related to non-hydraulic issues.
case studies, early warning, fl ood hazard, mathematical models
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