Numerical simulation of fluvial floods and sediment transport in urban stretch of the Araguaia River

Abstract

ABSTRACT: Brazil is a privileged country in terms of its hydrographic network. Thus, the rational and sustainable use of its rivers is a relevant task. In this paper, an assessment of river scenarios involving floods and sediment transport using the Finite Differences Method for numerical simulation is presented, as well as its application, considering the hydrological data pertinent to the Araguaia River in an urban stretch of the region of Barra do Garças in Mato Grosso. Using the Burgers equation, the numerical simulation of the flood problem provided a temporal evolution of the river volume as well as the formation of hydraulic jumps, which characterize the floods. As for the silting problem, the numerical solutions described the variations in the moving bottom of the river and the regions with significant sediment transport impact. The results showed a significant erosion process for the study scenario, lowering its thalweg downstream quota by 3 m and a total volume of moving solid of 759,770 m³, approximately 25 m³ of sediment carried daily. They can also serve to complement the discussions of environmental agencies, confirming the need for corrective actions such as dredging, reforestation and river banks evacuation.