The AAI of Hydrographic Basins is a methodological approach that uses environmental indicators of fragility and potential of river basins that may undergo changes (physical, chemical, biological and anthropic) due to the implementation of a set of hydropower plants. As a result, the river basin is ranked based on the Distributed Environmental Assessment (AAD in portuguese).
The AAI also identifies the main impacts of the planned and existing hydropower plants and evaluates the cumulative effects of these impacts on the weaknesses and potentialities of the basin, resulting in its sensitivity map. This map subsidizes plans, programs and projects, the expected effects of the implementation of hydropower plants, and also the guidelines and recommendations for the river basin management, the environmental licensing of the power plants and the accomplishment of specific studies by the entrepreneur of the hydroelectric plant.
The first AAI carried out by EPE was for the Uruguay River Basin. After were realized, also by EPE, the AAIs of the Paranaíba, Tocantins, Parnaíba, Doce, Paraíba do Sul and Teles Pires river basins. In 2007, the AAI methodology was inserted in the Hydrographic Basin Hydroelectric Inventory Study Manual, anticipating the stage of appreciation of the river basin as a planning unit provided for in Conama's Resolution No. 01 of 1986 for the environmental licensing of hydroelectric plants.