Quality of the environment is a very important prerequisite for sustainable development of the territory and improvement of the inhabitant life quality. Basin of river Lielupe in Latvia and Lithuania contains more than 250 confluents and about 840 thousand inhabitants of both countries live there. Compared to other river basins in both countries, quality of water in the river basin of Lielupe is one of the lowest. This is caused directly by intensive agriculture and multiplying nutrients in the water. It expedites grassing of rivers and endangers survival of several biotopes. Project includes water management measures for improvement of the conditions in the basin of river Lielupe. Research on seasonal fluctuation of water quality will be elaborated and rest places will be created next to the watercourse. One of the major aims of the project is to raise public awareness on these topics. The aim will be achieved by organising educational campaigns for inhabitants in the rest places. These campaigns shall address water quality issues and generate recommendations on improvements. At the same time, to ensure wide availability of up-to-date information, new web portal will be developed. Attention of adolescents to these issues will be raised during an interactive cross-border summer school. Project will generate the society extensive knowledge about water quality in the river Lielupe and principles of river basin management. River banks and bed will be cleaned, and nature infrastructure will be installed, as well.