The study develops a relationship between suspended sediment load and discharge for three basins - Kasol, Suni and Lower Satluj. The sediment load (tonnes/ year) and sediment yield (tonnes/ sqkm/ year) in suspension and as bed load of sand & gravel through the river channel, reflects upland erosion in the drainage basin and deposition of sediments in the alluvial bottomlands. A good deal of the sediment eroded from upland areas is deposited on lower hills slopes, in bottomlands, lakes and reservoirs.

An assessment of erosion is considered essential for land and water management, and an estimation of sediment transport and storage in lowlands, reservoirs and estuaries is critical for design and operation of irrigation and hydropower systems. Generally, suspended sediment loads are estimated using an empirical relationship between suspended sediment load and discharge. The relation is usually defined as a power function and is referred to as the suspended rating curve.

Daily suspended sediment and runoff data were collected from the Bhakra Beas Management Board (BBMB) for the period. The estimation of sediment was carried out by means of empirically developed relationships using various parameters like geomorphology, landuse and topography generated through Geographic Information Systems (GIS) technique. The digital representation of the catchment was used for hydrologic modeling.

The sediment yield was estimated for first three years and the relationship developed was used to simulate the value of sediment yield for the remaining three years. There is a reasonably good concurrence between the estimated and observed data. 

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