摘要：Degradation of freshwater resources has become a major issue of this century in many parts of the world. In order to ensure urban sustainability, decision support system (DSS) is a useful tool to help in water balance and to predict the various scenarios according to the scope of reuse. In the present paper, a framework for decision support system for urban water balance (DSSUWB) has been proposed. A graphical user interface (GUI) has been developed incorporating seven wastewater treatment technologies (WWTT) with six treated wastewater reuse options and two disposal options. The developed system has been validated using available data for Varanasi city (Uttar Pradesh, India). The indicative results suggest that the annual groundwater extraction is 89.1 MCM and annual water balance is estimated as -100.4 MCM which is too low. However, forecasted demand for the next 15 years will be increasing significantly by 37%. The estimated annual storm water of 55.3 MCM and untreated wastewater of 73 MCM requires a proper management which may contribute to help in future water balance. Three scenarios were considered for water reuse, which show that if water reuse capacity increased to 20%, 30% and 50%, then the water balance will improve by 32.9%, 49.27% and 82.12% and water extraction will reduce by 24.1%, 36.14% and 59.10% respectively. Hence, wastewater treatment technology selection has to be made considering the potential of reuse and there is requirement of separate infrastructure for storm water within urban boundary.
关键词：Wastewater reuse;Wastewater treatment;Urban water balance;Urban sustainability
