Effects of land use changes around a reservoir on sediment transport yields: HPP Itumbiara, Brazil

Soil erosion and deposition mechanisms, and associated mitigation measures, play an indispensable role in assessing the sustainability of both the existing reservoirs and newly planned projects. Land use is rated as one of the most important factors influencing water quantity and quality, as well as sediment transport yields, outflowing from surrounding watersheds into reservoirs. Therefore, appropriate land use management strategies are needed to ensure direct influenced by the reservoir of a hydroelectric power plant can provide the lessening of the capacity of power generation due to loss of useful volume. In Brazil because of the large dimensions of the reservoirs of hydroelectric plants, low-cost alternatives should be prioritized. Therefore this paper analyses the case of Itumbiara Hydropower Plant - Brazil, the sixth largest Brazilian hydropower plant. Four different scenarios were proposed: buffer with 20 m, 40 m, 100 m and 200 m of Indian grass at the edge of a stretch of the watershed area contained in the area of direct influence by the reservoir. SWAT software was used to perform the modelling of scenarios, with support from other softwares. As a result it may notice that occurs reduction of sediments transported to the reservoir, between 0.2% and 1.0 % per year and this value along the HPP Itumbiara life may be relevant.