The Simulation of Sediment Transport and the Determination of the Total Volume of Alluvium Using MIKE 21 Software—Case Study: The Șolea Stream (Vâlsan Basin), Romania

This study presents a methodology for extracting precise insights on sediment transport in the minor bed of a watercourse using MIKE 21 hydrodynamic modelling software. By integrating geotechnical, geomorphological, and hydrological datasets with a good-resolution Digital Terrain Model (DTM), sediment quantities along a 4.9 km stretch of the Șolea stream—spanning from its source to its confluence with the Vâlsan River (Argeș hydrographic basin)—were determined. A three-month simulation using MIKE 21’s “Mud Transport Module” enabled the comparison of pre- and post-simulation terrain models, yielding detailed information on sediment distribution across the riverbed. These results offer predictive capabilities regarding erosional dynamics and inform mitigation measures to address sedimentary erosion within the study area. The study also presents proposals for land reclamation necessary to prevent the degradation of the riverbed and slopes, such as gabion retaining walls and check dams in the riverbed.