A 2-D reservoir routing model: Sedimentation history of Abbeystead Reservoir, UK

A physically based two-dimensional model is applied to the case-study site of Abbeystead Reservoir, U.K. The model, developed for density currents, so lves the Navier-Stokes equation coupled to a general sediment transport equ ation. Water flow and sediment motion are determined by reference to dimens ionless Reynolds and Richardson numbers. An additional dimensionless parame ter, pia, determines suspended and/or bedload sediment transport rates. The performance of the model is considered in relation to data obtained from r epeated bathymetric surveys (1876-1991) for Abbeystead Reservoir, which pro vides an exceptionally detailed long-term record of sedimentation rates and deposition patterns. The suitability of the adopted two-dimensional scheme is related to the local morphology of the reservoir and the time-scale of the delta propagation process. First results show good agreement between th e numerical simulations and the field data. The model is able to reproduce both the dynamics of delta growth and the quasi-equilibrium delta form reac hed as the infilling process nears completion.