This research aims to identify the vulnerabilities of Rio Grande basin in Minas Gerais state as well as to investigate, through technical, legal, social, and governmental aspects, the relevance of SEA as an environmental tool for the conservation and preservation of watersheds. Rio Grande basin evaluation was performed by using this following database: soil classes, land use classifi cation, water quality index, and economic ecological index. It was performed multi-criteria decision analysis based on analytic hierarchy process methodology. 52.5% of the studied area was classifi ed as “good” preservation condition. Alto Grande (GD1), Mortes/Jacaré (GD2) and Furnas (GD3) units did not contain signifi cant percentages of their areas corresponding to the preservation class “very good”. In the studied area, 34.51% was classifi ed as “medium” preservation condition, thus indicating the need for effective measures for the river basin conservation. These fi ndings highlight the potential importance of including the SEA in the decision-making process for plans, policies and programs related to the integrated management of water resources.
