An Integrated Decision Support System for Managing Flood Events in a Complex Reclamation Territory (PAP014350)
Gianni Tebaldi, Marco Franchini, Marco Volpin, Laura Montanari
Flood forecasting and early warning systems
The Pianura di Ferrara Water Board covers the entire Ferrara province (North Italy) and is delimitated by suspended rivers and by the Adriatic sea. Approximately 50% of the entire territory is below the sea level (- 4 m), while the altimetry of the remaining part, mainly to the west, ranges between 0 m and +6 m (0 ? mean sea level). Most of the area is dedicated to farming, however many urban centres with historical monuments, main roads and hospitals are also present and several tourist centres are located along the coastline. The extensive agricultural activity in the area and the environmental protection require a considerable amount of water to be distributed using a channel network for about 7 months per year. However, both hydraulic protection and irrigation are performed through the same intricate channel network and regulated by a great number of control structures. The high vulnerability to flooding of the entire area is currently growing as a consequence of the climatic conditions which are changing, ground subsidence, sea eustasy and reduced absorption capacity of the soil due to general and continuous urban development. The increasing reduction of the safety margin for protection against floods involves structural interventions and operational optimization. In particular, the most recent and important initiative is the project for a modern and advanced Decision Support System (DSS). This system is based on a continuous hydrological rainfall runoff model, which runs in real time, and on a simplified one-dimensional hydraulic scheme for most of the basins and on a full hydraulic one-dimensional model for 5 of them, all fed by continuously updated information. The system provides important information to the decision makers through the estimation of the potential impacts of the current actions carried out on control structures. Future development will allow for analysing the effect of several policies regarding the management of the control structures. In detail, the current system receives in real time rainfall observations both from rain-gauges and the meteorological radar managed by ARPA (Regional Local Authority). Moreover, it uses rainfall forecasts performed by the Limited Area Model which is run by ARPA twice a day. For each elementary basin, the DSS carries out a hydrological and a simplified hydrodinamic simulation, whose results are used to estimate the safety thresholds and when the safety thresholds are forced, the decision makers is immediately alerted. In more detail, in the current version of DSS, the whole network of 5 selected basins is simulated through a full one-dimensional hydraulic model by taking into account the effective state of control structures and pumping stations. The decision makers will define optimal strategy of intervention by observing the DSS results which are currently based on a predefined operational scenarios which considers the actual configuration of all the devices dislocated along the hydraulic network. Furthermore, all the relevant data are available in real time for different Agencies and Organisations involved in flood emergency management in order to minimize damages to the environment and people.