The application of GIS to irrigation water resource management in England and Wales

This paper reviews the nature of agricultural spray irrigation in England and Wales, and the emerging role of Geographic Information Systems (GIS) as a modelling and decision-making tool to irrigation water resource management. Agricultural demand for water accounts for only two per cent of the total water use in the UK, but forms a significant component of direct abstraction in certain catchments in dry Summers and in dry years. The temporal and spatial variations in demand (as well as supply)cause acute problems for managing existing water supplies and planning future needs. Water resource managers need to base their catchment strategies on predicted irrigation demands and growth rates which take into account the local variations in climate, soil type, land use and irrigation practice, A GIS approach is particularly well suited to this. The availability of appropriate data sources, together with some recent example applications, are reported.