Runoff Simulation of Lam Chiang Krai Watershed Using SWAT Model

Abstract

Lam Chiang Krai Reservoir caused a dam to collapse, possibly due to a change of hydrological conditions from its design and the high amount of rainfall due to Tropical Storm Dian Mu causing severe flooding in the Lam Chiang Krai Basin in 2021. The simulation that helps to learn the hydrological conditions is another method to support reservoir management plans. This study simulates the runoff entering Lam Chiang Krai Reservoir using the SWAT model together with the analysis of the extreme runoff with different return periods. The results showed that the SWAT model gave the simulated results of the runoff at the relation of R² = 0.72 and NSE = 0.71 compared to the actual data measured at the Lam Chiang Krai Reservoir station. The results of the extreme runoff study use the Log Pearson distribution (type III) for estimating the amount of runoff in the Lam Chiang Krai Reservoir at return periods of 25, 50 and 100 years. Also, the results of this study can be suggested to prevent dam subsidence and increase the efficiency of Lam Chiang Krai Reservoir in the future.