Quantitative analysis of environmental impact assessments of hydroelectric power plants on the IBAMA database and evaluation of the hydrological parameters used

Environmental impact assessment is a determining tool for the implementation or not of all types of developments that can cause some imbalance in the surrounding environment. Brazil is known for its strict environmental legislation, requiring detailed projects that provide sustainable development at the site of implantation. Thus, Brazilian hydroelectric power plants are required to issue an Environmental Impact Assessment. In this study, environmental studies related to 30 Brazilian hydroelectric plants, available at the database of the Brazilian Institute of Environment and Renewable Natural Resources (IBAMA), were evaluated in order to temporally assess how many and which hydrological parameters were addressed in the environmental impact assessment. The hydroelectric plants are inserted directly into waterways, interfering or being directly influenced by rainfall, flow and sediment deposits. The results showed a tendency of adopting the same parameters. The creation of legislation that requires studies of certain variables may facilitate future comparison of the environmental impacts generated after the construction of hydroelectric plants.