Reconstructing historic reservoir sedimentation rates using data-based mechanistic modelling

This paper reports an application of data-based mechanistic (DBM) modelling to the study of reservoir sedimentation. A detailed monitoring programme i n the catchment of the Wyresdale Park reservoir was used to calibrate a two component DBM sedimentation model. The first component was a non-linear ra infall to suspended sediment load (SSL, kg s(-1)) model, the second dealt w ith sediment routing and the trap efficiency of the reservoir. Daily precip itation data for the period 1911-1996 were used to simulate the sedimentati on history of the reservoir. The synthetic accretion sequence evidences the effects of climatic forcing and was compared to lake-bed sediment cores in dependently dated using Cs-137. Th, synthetic stack showed general agreemen t with the observed accretion data. Departures in model performance most li kely reflect nonstationarity in the system due to local changes in land use and reservoir regulation. (C) 2000 Elsevier Science Ltd. All rights reserv ed.