Abstract
To assess the vulnerability of urban water supply systems, in regions even with limited accessible data, a proper index is required. Therefore, we developed a method to assess the drought risk using basic flow characteristics. Here, we suggested calculating water shortage index using intake volume, daily discharge, water demand, inhabitants served and water source type at each river basin. This method was applied in major rivers in Japan but considering its applicability in developing countries. The results show Yoshino River with the highest drought risk while Yodo River with the lowest risk. Actually, Yoshino River was found more vulnerable against change of intake amount for agricultural use. On the other hand, Arakawa and Abukuma Rivers were sensitive due to change of water demand depending on population change. The obtained water shortage indices were compared to actual reported droughts in Japan, and logic connection was found. Thus, water shortage index might be useful to analyze drought risk in other rivers.
