This project aims at safeguarding the Isonzo-Soča river and its host of tributaries through the treatment of urban waste water. The Isonzo-Soča is a cross-border river with its source in the territory of the Republic of Slovenia at the heart of the Julian Alps, it enters Italy at Solkan (Salcano) and finally flows on the Adriatic Sea. Its hydrographic basin covers a surface of more than 3,400 km2, one third of which in Italian territory. In addition to being an important water resource, the Isonzo-Soča also plays a significant environmental role (as the water habitat of several animal and plant species) and a tourist one too, therefore it must be safeguarded. Its tributaries include the Natisone river, which flows into the Torre stream and receives the waste water generated in the area of Manzano and Cividale. In this area the environmental situation is at risk, and is worsened by the fact that the Natisone is characterised by a markedly shooting flow and the special morphology of its bed, which result in the considerable variability in its flow rate, so much so that in summer flow rate values may drop to a mere few cubic metres. The “DISO-MA” project consists in the upgrading of the two water treatment plants located in the Municipality of Manzano, one at Case - on the left river bank - and one at Manzano - on the right bank of the Natisone. The sewage treatment line, in particular, will be adapted based on current quantitative and qualitative characteristics of the affluent flow, according to legal requirements in force and in view of a future increase in user demand. The project, that transfers to Italy the experience acquired by Slovenian Municipalities that are partners in the framework of mirror-like actions of creation and/or modernization of waste water plants funded under PHARE-CBC Programme ECO-ADRIA 2001, intends to contribute to the joint protection of the environment in the cross-border area. It also envisages the organisation of technical meetings with visits to the plants located in Slovenia and in Friuli Venezia Giulia to foster the mutual transfer of know-how, and the promotion and dissemination of the results achieved, to be illustrated on the occasion of special events.