Urban Water Management Using Water Self-sufficiency

Abstract

Water demand is increasing because of population increases and industry developments as well as demands for improved living standards. Existing water treatment and supply systems cover large areas and have a centralized system; consequently, development of new water resources requires a construction of pipe infrastructure over long distances. The variability of water quantity, as climate changes, is hampering efforts to secure water resources and decide facility capacity. Therefore, a new urban water management system to address these problems is required. This study suggests such a system as well as a new index, i.e., the water self-sufficiency ratio (WSSR) for evaluating the system. WSSR is calculated by dividing the total self-provided water quantity with the total water use in a city. The current WSSR for Suwon City is 11 %, but there are plans to achieve 50 %. This would be accomplished by using rainwater (26.8 million ton/year), encouraging water conservation (31.3 million ton/year), building tunnel-type rainwater-retention facilities (2.5 million ton/year) and reusing treated sewage (1.72 million ton/year). In addition, financial incentives are expected through such as reduction of floor area proportion, tax reduction and governmental subsidies. The WSSR is expected to be useful in evaluating urban water self-reliance as well as in quantitativly establishing a sustainable water management system.