Natural flow in managed catchments: A case study of a modelling approach

In the U.K., the water resources of many catchments are heavily managed and the existing constraints on their use must be built into future management. Recent developments in catchment modelling mean that the practical use of models, to analyse catchment behaviour and assist with the management process, is a feasible option. However, few models include appropriate water management components that will permit application to those areas for which they are most needed. This paper describes the integration of simple management controls into a spatially distributed hydrological model and illustrates how the model can be used to assist in catchment management, through a case study of the Carron catchment in Central Scotland. The model was successfully applied to predict flow in both the upland region of the catchment, where there are several reservoirs and significant transfers of water and the lowland region of the catchment, which is a predominantly urban area. A simple modification to the water management procedures illustrates how the model may be used to help achieve naturalisation of the flow regime, thus satisfying the requirements of the precautionary principle.