Future flows and groundwater levels : R-groundwater model summary

This report is the result of research commissioned and funded by the Environment Agency’s Science Programme, the Department for Environment, Food and Rural Affairs, UK Water Industry Research and the Natural Environment Research Council. It describes the structure of the R-Groundwater model that is used to simulate groundwater level hydrographs at a series of observation boreholes identified for analysis within the project. R-Groundwater is a simple lumped catchment groundwater model written in the R programming language and run within the R environment. It has been developed to model groundwater level time series at observation boreholes by linking simple algorithms to simulate soil drainage, the transfer of water through the unsaturated zone and groundwater flow. Time-series of flow through the outlets of the groundwater store are also generated, which can be related to river flow measurements. The model is calibrated through a Monte Carlo process by randomly selecting input parameter values from ranges specified by the user. Simple text files are used to define the input to the model and to write the output.