This study provides the sedimentation rates (SR) of three drainage basins at Itaipu Reservoir (Paraná State, Brazil) by applying 210Pb and 137Cs geochronological methods (CFCS and CRS models). The results based on the CRS model showed SR increasing in São Francisco Verdadeiro (SFV) and Ocoí (OCO) over the last decades (0.61 and 0.43 g cm2 yr−1, respectively). Arroio Fundo (ARF) showed the opposite trend with decreasing accumulation (0.19 g cm2 yr−1). The SR results indicate that precipitation changes in a period of rapid agricultural development influence each sub-basin differently depending on its drainage size area and watershed conditions. [ABSTRACT FROM AUTHOR]