Reports and Papers
River basin management has obvious spatial dimensions, since it is focused on a spatial unit, the hydrological catchment, in the first place. This makes the use of GIS, and its integration with traditional water resources models, and obvious strategy for the development of river basin management systems (Fedra, 1993a; Maidment, 1993).
While the GIS is used to capture, analyze, and display spatial data, the models provide the tools for complex and dynamic analysis. Input for spatially distributes models, as well as their output, can be treated as map overlays and topical maps (Fedra, 1994) . The familiar format of maps supports the understanding of model results, but provides also a convenient interface to spatially referenced data. And expert systems, simulation and optimization models add the possibility for complex, and dynamic analysis to the GIS (Fedra 1992, 1993b).
The main challenge in building effective river basin information systems is the integration of dynamic models with the capabilities of GIS. The GIS can provide a common framework of reference for the various tools and models addressing a range of problems in river basin management. In a multi-media framework, it can also provide a common interface to the various functions of an integrated river basin information and decision support system. This interface has to translate the data and model functionality available into information that can directly support decision making processes (Fedra, 1995).
Object-oriented design provides some of the flexibility for building highly integrated information systems, utilizing existing software components, but supporting a high degree of customization (Abbott 1993; Raper and Livingstone 1995).