This paper presents results achieved within the AQUIFER project and from applying a remote sensing approach for regional scale water and vegetation monitoring in the Sahel. This area is characterized by important interaction between climate variability and socio-economic key factors like agriculture and water resources. The present study is focussing on surface water and vegetation monitoring over the Iullemeden Aquifer System. The groundwater of the Iullemeden Aquifer System (IAS) is composed by two major aquifers: the cretaceous Continental Intercalaire and the tertiary and quaternary Continental Terminal. This Aquifer system is affected by progressive over-extraction, water quality degradation human induced pollution, associated with soil degradation, and the impacts of variability and climatic change. The specific vegetation and the open surface water bodies in these arid regions are good indicators for environmental change. In many parts of the Sahel there are no continuous ground truth measurements available to allow statements about the extension of vegetation and open water bodies. Earth Observation data may provide the only approach to detect and analyse long-term changes and it allows to monitor the negative impacts of human activities and climatic change of the available water resources in this area. This study demonstrates the performance and suitability of ENVISAT MERIS and ASAR-WS data for this purpose. Land cover classification maps of four different points in time within one growth period were generated using a rule based (object oriented) classification approach. Additionally, the changes between the four different dates as well as the seasonal vegetation dynamics were analysed.