Comparison of results obtained using a distributed urban storm-water model with GIS or traditional input

In this paper a Geographic Information System (GIS) and a Digital Elevation Model (DTM) for large urban areas based on all the information needed for urban storm-water modelling, has been realised. The study area is an experimental catchment in Cosenza, a city of Southern Italy, partly urbanised (202 ha and partly natural 212 ha), equipped by rain gauges and an ultrasonic level gauge. The catchment is served by a combined sewer system. A specific cure has been given both to developing and processing the urban data set and to deriving the DTM. The last data permit to calculate surface flow path and contributing area to each inlet. The GIS has been used togheter with a diffused rainfall-runoff model, MOUSE, to simulate a good number of experimental events with the aim to compare these results with those carried out by a traditional input.