The paper analyzes the impact of the regulation of natural streams on the changes in hydraulic parameters, with a particular focus on flow velocity, bed slope, and tangential stresses. The first step in the research was the development of numerical models for flow in both the natural and regulated channels, based on geodetic, hydrological data, and bed roughness data. The numerical models were created using HEC-RAS software, version 5.0.7. Hydrological data on high-water events used in the numerical models were calculated based on meteorological data using the Rational Method. After the simulations were conducted, a comparison of the hydraulic parameters in both scenarios was performed. The results showed an increase in flow velocity and tangential stresses along almost the entire section, suggesting an increase in erosion and sediment transport. The research covered the area of the Osojački stream and its collision with the Tuzla-Orašje highway, which prompted the regulation of the watercourse. The correction of the natural stream’s course during regulation led to the disappearance of meanders, which could have a significant impact on the processes within the river ecosystem.