Estimation Of Sediment Inflow Into A Reservoir Using Combined Approach Of Rainfall: Runoff Modelling And Sediment Transport Assessment

Reservoir sedimentation can affect both operation and safety of dam if it is not properly managed. It adversely affects the multiple functions of dam and has become one of the major concerns for the owner and operator. This study describes methods to predict total inflow of sediment into the Ringlet Reservoir in Cameron Highlands using integrated approach of catchment rainfall runoff modeling and sediment rating curves derived from field sampling. MIKE NAM is used to simulate the runoff generated from the Cameron Highlands’ catchment. This model is developed, calibrated and validated using the flow data of Sg Bertam. Field sampling is conducted to measure the Total Suspended Solids (TSS), Bed Load and grab samples at major rivers of the catchment. Sediment rating curves are developed to describe the relationship between the total sediment load and discharge. The available sampling data, hydrology records and catchment ratio are used in determining the total sediment inflow into Ringlet Reservoir, which is between 150,000 m/year to 200,000 m/year. This information is useful for the reservoir manager to plan for the most suitable sediment management.