Methodologies to study the surface hydraulic behavior of urban catchments during storm events.

A good knowledge of the hydraulic behaviour of an urban catchment and its surface drainagesystem is an essential requirement to guarantee traffic and pedestrian safety. In many cases, inletshave been situated according to spatial density criteria. Indeed a more rational location of inlets onurban catchments must be defined according to an accurate analysis of the relationship betweenstreet flow and inlet hydraulic efficiency. Moreover we lack specific hazard criteria in terms of themaximum acceptable flow depths and velocities on the streets that do not cause problems topedestrians. In this paper the results of two different experimental campaigns are presented. Thefirst was carried out to evaluate inlet hydraulic efficiency; the second was carried out to addressthe pedestrian stability in urban flood conditions, whose aim was to propose new hazard criteria.On the basis of the experimental results, a methodology was developed to assess flood hazard inurban areas during storm events. If a refined topographic representation of urban areas isavailable, a two-dimensional numerical simulation of urban flooding can be performed usingcomplete shallow water equations. According to this approach a numerical application for floodhazard assessment in a street of Barcelona is shown.