Assessment of sediment load in upstream of the Vu Gia - Thu Bon river basin by swat semi distribution hydrological model

Abstract

   The Vu Gia - Thu Bon river basin is one of the river basins has large hydropower resources in the country. At present, many reservoirs are planned and constructed in the basin. However, a major problem in the exploitation of reservoirs is the determination of sediment load in the reservoir over time. In this study, the authors will use the SWAT semi-distribution model to determine the sediment load at the site of 4 large reservoirs upstream of Vu Gia - Thu Bon river basin: A Vuong, Song Bung 4, Dakmai 4 and Tranh 2 river during 31 years, from 1980 to 2010. The results show that the sediment load in the reservoirs is mainly concentrated in four months of flood season (9, 10, 11, 12). The average sediment load during the flood season in four A Vuong, Song Bung 4, Dakmi 4 and Tranh 2 reservoirs was 1733.76 tons, 40610.90 tons, 71593.86 tons, 77374.78 tons, respectively, accounting for 85.84%, 78.49% 82.72%, 82.19% of average annual sediment load.