The Himalayan Rivers have a complex nature in terms of hydraulics and sediment transport capacity, which is a great challenge for civil and hydraulic engineers in designing the headworks of a hydropower project. The conventional and numerical analysis and design of hydraulic structures only are inadequate to represent the behavior of a complex river system. Hence, the physical models of hydraulic structures are the only tools that can be used to analyze complex behavior and efficiently design headworks on such rivers. The physical models are used to predict and visualize the performance and effects of the proposed design in reduced-scale models in a laboratory experiment. This study’s headworks model scale of 1:30 is constructed of hydropower in the Nepal Himalayas at the Hydraulic Structures Laboratory of Kathmandu University. The headworks include the weir, intake, gravel trap, approach canal, and desanding basin. To represent the required flow in the river, the model headworks is constructed to include a river section at a distance of 100 m upstream and 500 m downstream from the weir, respectively. The flow parameters like discharge and velocity have been modelled at a suitable scale ratio using the Froude Law. As per the river’s hydrology, an appropriate discharge was released into the model river. The diverted discharge through the intake and remaining discharge over the weir was measured using a suitably placed discharge measuring instrument and a right-angled triangular weir. The diverted discharge through the model intake is validated with the actual design discharge of the project. The discharges at different sections will also be analyzed using HEC-RAS and verified on the model. Such model experiments are helpful for students, researchers, and industries to study the hydraulic phenomena of rivers, canals, and the design of hydraulic structures.