Detail Abstract

Watershed hydrological model for discharge and sediment simulation in Vu Gia Thu Bon river basin using HYPE model

Abstract

Vietnam has experienced several problems with its water resources, particularly floods, which have been a major worry for farmers for many years. Vietnam is one of the most flood-prone and climate change-affected countries, with more than 3,200 kilometers of coastline and 80% of the people residing there (Dasgupta S. et al., 2007). The most obvious human activities that affect Vietnam\'s water quality and quantity are watershed deforestations and the building of hydroelectric power facilities. Excessive flood episodes, which can result in poor water quality or inundation in the downstream communities, are one of the most important problems caused by these human activities. One of Vietnam\'s greatest internal drainage systems is the Vu Gia Thu Bon (VGTB) river basins in Central. Two significant rivers, the Vu Gia and the Thu Bon, together make up the VGTB river system (Firoz. et al., 2018). Regarding water, food, energy, as well as cultural and recreational activities, the VGTB river basin has a significant impact on the way of life of the locals. By applying the Hydrological Predictions for the Environment (HYPE) model, conducting the discharge and suspended sediment concentration (SSC) simulation for the VGTB river basin in two cases with and without reservoir to see the change of streamflow and SSC in case of reservoir presence.</br> NSE values for Nong Son and Thanh My stations with daily scale for model performance in “natural” (without reservoirs, before 2010) conditions in the VGTB river basin were 0.78 and 0.46, respectively. The KGE values for the VGTB river basin\'s model performance under-regulated (with reservoirs, after 2009) conditions are 0.513 for the daily scale and 0.516 for the monthly scale. Therefore, the HYPE model shows potential results with the Nong Son and Thanh My hydrology station within the VGTB river basin. With the goal of providing more realistic simulations for reservoir operation of managers and flood control plans, HYPE will be continuing to finalize in VGTB by integrating the reservoir operation.