The lion share of the work goes to small partial catchment areas of up to approximately 300 square kilometers. Their consideration places high demands on the planning. An enormous significance must be attached to an unambiguous information management in order to involve the public in appropriate manner.

A project under management of the company SYDRO Consult GbR (Darmstadt) developed methods for the support of this decision making procedure. At the example of three different water catchment areas, the involved experts described demands and problems of integrated water economy systematically. On this basis, the modular built »Decision Support System« (DSS) is a tool, with which the integrated water-economic planning can be shaped essentially more effectively.

The DSS mainly consists of the »Geographical Information System« (GIS), administration of time series as well as of modelling and evaluation of the applications. Simulation models determine the effects of different scenarios. These find their way into the evaluation process, which clarifies the interesting target figures for the decision makers and allows a comparison of the alternatives. The concept can be transferred on all catchment areas and is a practical and efficient work basis for the water protection planning.