Multi-period consequence management of contaminations in water distribution networks: application of regret-based optimization model

This study presents a Regret-based optimization model for multi-period consequence management of contaminations entering the WDNs considering the pollutants loads' entry uncertainties. For this purpose, first, the EPANET software is utilized as a water quality-quantity simulation modeling tool. Then, an optimization model based on a genetic algorithm using the primary objective functions of minimizing the return time of the contaminated WDNs to the normal mode, the amount of pollution, and the number of polluted nodes. Besides, the pollutant load-related uncertainties are included in the presented simulation-optimization model by minimizing the maximum Regret (MMR) and the total Regret (MTR) in two steady and dynamic status for all three mentioned objective functions. Using these nine objective functions, three management instruments are utilized: quick closing valves, discharging hydrants, and boosting pumps. The results show that the proposed model can effectively prevent harmful pollution by offering effective management strategies, mainly in dynamic status scenarios.