Simulation of Reservoir Siltation with a Process-based Soil Loss and Deposition Model

Soil erosion on arable land is the key driver of reservoir siltation in the German loess belt. In this regard, the Baderitz Reservoir suffers from deleterious sediment inputs and resulting siltation processes. In order to estimate the reservoir lifespan, the event-based soil erosion and deposition model EROSION 3D was applied. Simulations of sediment input and sediment deposition processes within the reservoir were realized using a typical crop rotation and a normal heavy rainfall year of the region. Model parameterization was enabled by existing data based on a large number of artificial rainfall simulations. Yearly soil losses of approximately 12 t/ha correspond to sediment inputs of nearly 8800 t. The mean annual increase of the reservoir bottom of 9 cm causes a 13% loss of reservoir storage in only 10 years. The model results are plausible and could be used for planning and dimensioning of mitigation measures