Assessment approach to the floodwater utilization potential of a basin and an empirical analysis from China

Abstract

Water stress is increasingly intense all over the world owing to rapid economic development and global climate change. Floodwater utilization can mitigate water shortages and provide multiple water use benefits. The priority of evaluating the utilization status and potential of floodwater should be taken into account at a basin scale. However, few studies have focused on the assessment approach. This paper argues that the amount of available floodwater is a function of the ability to regulate and utilize floodwater, and that floodwater can be classified into two parts: unavailable floodwater and available floodwater. Based on this definition, the logical relationships among current floodwater utilization potential, theoretical floodwater utilization potential, and the current and theoretical amounts of available floodwater in a basin were derived using limit analysis theory. The concepts and evaluation methods of basin floodwater utilization were unified in this paper. Finally, the status and potential of floodwater utilization of the Nansi Lake Basin were evaluated. The results showed that the current and theoretical amounts of available floodwater were 1629–1808 million m3 and 2050–2155 million m3, respectively, and the current and theoretical amounts of floodwater utilization potential were 266–386 million m3 and 678–733 million m3, respectively. The application in the Nansi Lake Basin offers some practical information for assessing floodwater utilization scientifically and provides some significant guidelines for other basins.