Estimation of suspended load portion as bed-load in Talar River, Mazandaran, Iran

Sediment deposition in water resources and reservoirs is a considerable issue in exploitation of water projects which causes environmental problems and reduces useful life of dams. Therefore, accurate estimation of the amount of sediments is a task that must be placed in planning and programming to deal with sediment issue in dims reservoirs. On the other hand, bed-load measurement is difficult and complicated and needs specific expertise and currently, it is conducted in some stations only for research. Hence, determination of this kind of sediment load by other approaches such as the equations of bed-load determination is required and necessary. Shirgah hydrometric station is located on Talar River which is one of the most important rivers in Mazandaran province. In the present study, considering the station data including discharge flow rate, discharge - scale curve, grain size and cross section area of the flow, bed-load of the station was estimated using bed-load determination methods including Shields method and Meyer-Peter & Muller method by which it can be found that, how many percent of suspended load can be considered as bed-load. This approach gives us a suitable criterion to determine bedload in the rivers. As the major result of this study, it can be stated that, bed-load coefficient must be estimated separately for each station to calculate bed-load with higher confidence level considering that, measurement of suspended load is much easier than for the bed-load

Keywords:

Suspended load , Bed-load , Talar River