Marine water quality is one of the priorities among contemporary Black Sea environmental issues. Its major importance and complex implications are evinced by international and national concerted concern and actions, such as the control of eutrophication and the financing of nutrient reduction supported by the Global Environment Facility (GEF), the continued European Union (EU) commitment to the Black Sea, the Strategic Action Plan for the Rehabilitation and Protection of the Black Sea with related National Action Plans for the entire region. Coastal water quality along the Romanian Black Sea coast will be considerably improved by the full operation of four wastewater treatment plants at Constantza Nord, Constantza Sud, Eforie Sud and Mangalia until the end of 2008: following main achievements are expected from the modernization of mentioned facilities: – conformity of wastewater quality parameters with European Economic Community (now EU) Directives, –improvement of quality control and ecological protection of coastal waters, – fulfillment of one of Romania's obligations as EU admission candidate country.