Aquacycle is a daily urban water balance model, developed by the Monash University of Australia, with the aim to simulate the total urban water cycle as an integrated whole. The goal was to provide a tool for investigating the use of locally generated stormwater and wastewater as a substitute for imported (fresh) water along side water use efficiency. Within SWITCH, Aquacycle has been used for the modeling of the urban water system of Alexandria in order to conduct scenarios for urban water management in Alexandria. The input data required for the model have been gathered concerning population, the adjusted household profile of water use of Alexandria, the industrial demands and water production of drinking water plants and its branches. All the gathered data have been entered into developed GIS system using Autocad, Ilwis and ARCGIS software. Maps illustrating the water production of drinking water plants and its branches have been constructed within the system. Distribution of water consumption from all layers, hotels, clubs and industrial has been developed within the GIS system.
The representation of the urban catchment of Alexandria was based primarily on a classification of land use types, focusing on residential and tourist areas. Therefore, 7 types of clusters were defined; Densely populated area, Suburban housing, Recreational Area, Informal Settlements, Summer houses. The characteristics of cluster types and building blocks and the identification of the corresponding clusters have been validated and modified. A comparison between the modeled water consumption and the real water consumption has been calculated in order to validate the model. The verification have been conducted on three levels, first on water treatment production level by calculating the water consumption in water treatment service area and make a comparison between the water production from the water treatment plant. Second level of verification has been implemented by comparing the water consumption for drinking water branch and the calculated water consumption from the model in the same branch area. The thirds level of verification has been conducted in a very detailed study by comparing the real water consumption at the cluster level and the calculated cluster water consumption by the model. The results of verification were satisfactory for the three levels, the error ranges from 2 to 5% which is considered acceptable in this type of application. Finally, scenario of the greywater reuse option for irrigation has been conducted using the developed model as and its effect on imported water saving and generated wastewater reduction and some recommendations for future studies have been illustrated.