Management of Regional German River Catchments (REGFLUD)- General conditions and policy options for diffuse pollution by agriculture of the river Rhine and Ems -

The REGFLUD-project addresses the problem of diffuse pollution that is largely caused by agricultural production. The overall objective is the development and application of multi-criteria scientific methods to set-up a Decision Support System aimed at reducing diffuse pollution in river catchments subject to economic feasibility and social acceptability. The project is structured according to four tasks: 1) Applying a model network consisting of an agricultural sector model, a water balance model, and a groundwater residence time/ denitrification model that enables consistent status-quo as well policy measures analyses. 2) Evaluating alternative agri-environmental measures with a benefit-cost approach based on interviews with stake holders (residents, water management, etc.) and experts about the social acceptability of alternative measures. While regional differentiated costs arise primarily from agricultural production losses due to nutrient reduction measures, regional differentiated benefits are assessed via the willingness to pay for improved water quality of residents. 3) Analysing alternative forms of organisation regarding an efficient and likewise nutrient surplus oriented water management. Precise recommendation pertaining to the management of diffuse nutrient discharges will be elaborated. 4) Summarizing and providing results within an online DSS for the interested public. The selected study area covers a wide range of different landscape units with different hydrological, hydro-geological and socio-economic characteristics which facilitates the extension of the REGFLUD-project to other landscapes and river basins. First results for the status quo indicate partly very high nitrogen surplus of more than 200 kg N per hectare agricultural land in the study region due to intensive livestock farming.