This project will investigate the calibration and verification methods used for flood forecasting models, with particular concern to the hydrologic models currently in use for planning, design, and operation of engineering systems to cope with extreme material events. Since the success of any calibration procedures is dependent on the quantity and quality of available and used data, the selection of the "most informative" data sets is of great importance, especially because, to date, existing calibration and verification approaches do not exploit the full potential of the information contained in the available data. A method and guidelines for appropriately evaluating the type and quantity of data used in flood forecasting models will be developed.