Use of HEC-RAS and HEC-HMS models with ArcView for hydrologic risk management

The paper discusses how the well known USACE HEC models, RAS and HMS, are fully integrated within the decision support system of the Romagna River Basins in order to predict flood effects. The models are fully available from the web and cope with such a variety of problems as rainfall-runoff modeling, river and civil works hydraulics, and the mapping of hydraulic hazard. The paper illustrates the methodology followed to integrate existing topographic and hydrologic data, calibrate both hydrologic and hydraulic models, and produce maps directly usable in land planning. The paper stresses the organizational problems involved in the development of such a decision support system, and sketches the main issues in pipelining general planning analysis and river training and management design, in order to achieve a fully self-updating decision support system which feeds back analysis results to design evaluations and again updated information from developed works to the prediction models.