THE USE OF GEOLOGICAL AND HYDROGEOLOGICAL MODELS IN THE ENVIRONMENT AGENCY OF ENGLAND AND WALES

Background The Environment Agency is the environmental regulator for England and Wales. Managing groundwater resources is one of our key roles. Assessment of the impact of abstraction on available resources and groundwater dependant surface waters and ecosystems is key to developing sustainable management strategies. In order to accomplish this, we have been making increased use of digital geological and hydrogeological modelling technology..

Where are we now?

3d Geological Models so far have been developed to aid understanding of areas where complex glacial or fluvial deposits make groundwater recharge and vulnerability issues particularly uncertain. We have commissioned the models from the British Geological Survey and they are viewed through the Lithoframe Viewer software.

Groundwater Models range from conceptual reports to fully distributed numerical groundwater models. We have recently developed our National Groundwater Modelling System (NGMS) which is based on the Delft FEWS software. This is a software front end that enables our models to be used effectively for both longer term resource planning and on a day to day basis.

Future Development

We are aiming, with the BGS, to develop digital regional and catchment scale geological cross sections. This should enable construction of a national geological fence model for use in environmental decision-making. In the long term the fence diagram model should represent an early step in the realisation of a full 3d geological model of England and Wales.

A project to utilise rainfall radar data available from our Flood Forecasting System (also FEWS based) is currently underway. Development of a real time radar data feed into NGMS would mean that near real time groundwater forecasting would be practical for the chalk aquifers and also enable localised but significant rainfall events (which often miss the rain gauge network) to be incorporated into the model calibrations.

The potential development of a 3d interface within the NGMS system will allow the Lithoframe Viewer to become integrated into NGMS. This would result in both the Environment Agency and British Geological Survey sharing a groundwater and geological modelling platform