Revision of Reservoir Sedimentation Model Using a “Sediment Storage Function”

Abstract

Since the global climate change will accelerate sediment yield from watersheds with increasing intensity and frequency of precipitation, many dams will more significantly suffer in future from losing their storage capacities with reservoir sedimentation. In this study, a conceptual model of reservoir sedimentation was proposed, where the sediment yield was estimated from land failures in the catchment and the sediment balance in the channel system was parameterized by a “sediment storage function”. The present model consisting of a couple of concentrated parameters is considerably simplified than so-called physical mechanistic models. Additionally, this has an advantage that reservoir sedimentation is successfully reproduced without using discharge dataset. By using the model, further discussion was made how much reservoir sedimentation will be accelerated in future climate.