Calibration and Reliability in Groundwater Modelling: Credibility of Modelling

(Proceedings of ModelCARE 2007 Conference, held in Denmark, September 2007). IAHS Publ. 320, 2008, 95-100.

The National Groundwater Modelling System for England and Wales

Rolf Farrell¹, Mark Whiteman¹ & Peter Gijsbers²

1 Environment Agency, Rivers House, 21 Park Square South, Leeds LS1 2QG, UK

rolf.farrell@environment-agency.gov.uk

2 Delft Hydraulics, Rotterdamseweg 185, 2629 HD Delft, The Netherlands

Abstract Groundwater modelling within the UK is dominated by the construction of large, regional-scale groundwater models primarily used for groundwater resource management by the Environment Agency for England and Wales. Due to their complexity they are installed individually on standalone computers, which restrict their use. To address this, the Environment Agency has instigated the National Groundwater Modelling System (NGMS) project. The NGMS system is a server-client system for holding groundwater models and supporting documentation, which enables models to be run and the input and output files to be viewed as required. NGMS is not a tool for developing new groundwater models; this can be conducted with existing tools being used in the UK such as Groundwater Vistas. Data can be viewed and plotted in many ways and any functionality not covered by NGMS is addressed by straightforward export of data to other applications. The software and hardware structure is based on the Delft Hydraulics FEWS system, which has been used to develop the successful Environment Agency National Flood Forecasting System (NFFS). Use of the system will result in greater standardisation of model codes and methods used by the Environment Agency without stifling technological progress. The use of standardised input data formats will make it easier for regional models to be updated so that they can be ready for use when operational needs demand it. NGMS allows local operational hydrogeologists and water resource management staff access to the models. This means that non-modellers will be using groundwater models and so, to ensure that the output is correctly interpreted, users will only gain access to NGMS if they have been formally trained in its use.

Key words regional-scale groundwater models; resource management; central server; user friendly; standardisation; operational needs; forecasting; training; accessibility