Background The Barlad river basin represents 17% of the surface of the Siret river basin - the largest in Romania and a major affluent of the Danube from the Eastern Romanian Carpathians. It is characterised by a high number of nitrate sources from agriculture and villages and has many ‘nitrate vulnerable’ zones. Along the 207 km of the Barlad river, at least 116 km is “at ecological risk” from pollution by nutrients coming from agriculture, non-treated domestic sources and industrial wastewater - particularly from the chemicals sector. Downstream of the city of Negresti, the nitrate concentration in the Barlad river is as high as 50 mg/l. In the 1990s, large areas of forest along the river were cleared, increasing the speed of nitrogen and phosphorus runoff. This trend is expected to increase as a result of climate change. Objectives The CLEANWATER project intends to develop, at the river-basin scale, an integrated water management system to identify waters under threat and designate vulnerable zones. This aims to provide the authorities with a means of developing effective river-basin management policies for the Barlad river and to assess their impact. The beneficiary will develop the management system based on the Strahler stream model of surface water flow and pollution transportation and the River Modelling System (RMS), which computes the transfer of nutrients in groundwater systems. The system will contain software capable of calculating the environmental impact of activities and changes. Given the data requirements of these models, the project will develop, test and implement a GIS platform which will collect data on features such as soil characteristics, the climate and village zootechnics (animal management). The management system will depict the current status of the water and predict future nitrate and phosphorous flows in the aquifers of the Barlad river basin based on projected changes in land-use, industrial activity and climate. Through a user interface, the relevant authorities will be able to use the scenarios generated by the system to define cost-effective river basin management plans. Expected results: The project expects to: Develop a GIS-based interface to predict the impact of natural changes and policy decisions on nutrient concentrations in the Barlad river basin; Facilitate the identification of cost-effective measures for river management; Provide support for land-use planning; and Contribute to a future national approach to zones vulnerable to nutrient pollution.