Development of a Dynamic Rule Curve for Reservoir Operation Using the Most Likely Line Technique for Water Management in the Ing River Basin

Abstract

Kwan Phayao has been facing persistent issues of water shortages and flooding. Despite the implementation of reservoir operation rule curves, current water management practices remain inconsistent with the area's specific context and the impacts of climate change. This study aims to develop a Dynamic Rule Curve by applying the Most Likely Line (MLL) technique, based on the analysis of 30 years of inflow and outflow data. The study found that simulating the application of the Dynamic Rule Curve (MLL) over a 30-year period resulted in a total overflow volume of 17.74 million cubic meters, with overflow occurring in 7 months. Furthermore, when applied to the actual flood event in 2024, the Dynamic Rule Curve reduced overflow 47.42 million when compared with last volume and decreased water discharge by 3.46 million cubic meters, thereby mitigating downstream impacts. These findings demonstrate that the Dynamic Rule Curve is effective in reducing flood volumes. Therefore, the developed Dynamic Rule Curve can be applied to enhance water management in Kwan Phayao. flood volume and discharge impacts.