Modelling the urban water system of Alexandria using the Aquacycle model

As in other cities in Egypt, water demand in the metropolitan area of Alexandria is rapidly increasing over time, as a result of urban expansion, amelioration of living standards and industrial development. As the River Nile is the main source of freshwater supply, concerns arise regarding a potential reduction in Alexandria9s allocation quota, which could affect population growth at the national level, agricultural development plans and water demand increase in the upstream areas. In this context, demand management and diversification of urban water supply are gradually gaining momentum among local authorities. The transition to a new paradigm for urban water management, including closed-loop systems at different levels to meet increasing water demands, has been the focus of a recent research effort, within the framework of the European-Commission-funded SWITCH Integrated Project. One relevant activity, whose results are presented in this study, concerned the development of an urban water balance model for the metropolitan area of Alexandria. The model, which was created using the Aquacycle software package, was further used for the preliminary assessment of decentralised solutions at different spatial scales, in order to evaluate their application potential and effectiveness in reducing freshwater imports to and wastewater outflows from the city.