The Western Mancha aquifer: data mapping to provide transparency to aid stakeholder participation and decision making

The paper presents a series of maps on the Western Mancha aquifer, an aquifer of 5,500 km 2, extending over an area of 41 villages in the region of La Mancha, in the central Spanish plateau. Maps were produced using cartograms, which highlight the differential groundwater use at the local level of the municipality, looking at equity and efficiency issues related to groundwater. The main purpose of the paper is to provide comprehensive, transparent and easily understandable mapping of groundwater use in a region where data is abundant but not necessarily consistent, clear or presented in an easily accessible or understandable format. The paper provides a meta-analysis in the form of maps of available data as a result of a large number of European research projects, national and European policy initiatives, but where a general multi-disciplinary and summative overview is still lacking. This mapping can contribute to decision making in public policy, as support for compliance with the European Union Water Framework Directive on good ecological status, in an area where there are competing, and in many ways incompatible, water demands between irrigation and wetlands. This analysis highlights that a spatially differentiated approach could provide win-win scenarios, i.e. intensive groundwater use and wetland protection.