Abstract: Sediment control is a key issue that needs to be addressed when a hydropower station takes water from a sandy river and generates electricity. This article presents an experimental study on sediment deposition, its developing trend, and sediment control for operating the Karot hydropower station in Pakistan through physical model tests. The results show that for this station, its sedimentation balance period will be extended up to 20 years if it adopts an optimized operation mode of grading selection timing for sand removal and a layout of dual bend sand diversion and water taking. Sediment accumulation in the river section 8.15 km upstream of the dam is 47.8 million m3, with an average deposit layer of 27.4 m thick and a maximum thickness of 51.7 m; The retention rate of the utilizable capacity is 78.6%. During water storage, sediment concentration in the flow through the turbines is decreased by 92.1%, while it is decreased by 33.7% before and after the flood season. Throughout a year, sediment concentration in the flow through the power plant unit will not exceed 1.2 kg/m3, and the largest prototype particle size passing through the turbine is 0.02 mm. Therefore, this station will not encounter the problem of coarse sediment passing through the turbine. The sediment discharge scheduling method and hub layout of the Karot hydropower station provide a solution to the sediment control of the sediment-rich river hydropower stations in plateau regions.

Key words: sandy rivers, hydropower station layout, water intake and sand prevention, bend, sedimentation in reservoir