Potential of environmental flow: participatory method for determining environmental flow in hydropower’s reservoirs in Amazon rivers

ABSTRACT

The potential of environmental flow (PVA) is an alternative method to estimate the flow as it mainly considers the ecological, economic and cultural characteristics of the basins, reducing estimation errors in the assessment of environmental impacts for deployment or operation of hydroelectric power plants (HPPs). The aim of this research was to adapt the PVA methodology for Amazon’s large basins using holistic approach. The methodology for estimating the PVA was adapted to the watersheds of the rivers Tocantins, in Pará, Jari, in Amapá and Pará, and Araguari, in Amapá, under operation and/or final installation of HPPs. The results suggest that, in the Tocantins and Araguari rivers, both under the influence of dams in operation, the most relevant parameter of PVA was water stress. Taking into account the direct impact of these HPPs, the flow rate is high enough to keep the ecosystem or aquatic diversity during the whole year. However, the response of the PVA in the Jari river basin, in the ultimate construction phase, the most relevant parameter was the economic dependence, because the priority is the fluvial transport, and, in this way, estimating the flow by a non-adequate method would jeopardize this very important function. We concluded that the PVA method is an interesting tool for managing large basins, because it is flexible, adaptable and especially allowing the participation of the agents involved in the decision making processes.

Keywords:
decision making process; holistic methods; participatory manage; Oriental Amazonia