Reassessment of Porto Primavera Reservoir sedimentation in view of updated sediment measurements

The Porto Primavera Dam is located on the Parana River, Brazil, downstream of the Jupia dam and upstream of the Itaipu dam. The reservoir capacity is 15.7 km³. The sediment load impounded in the reservoir mainly comes from six tributaries located in a drainage area of 574 000 km ². Low dam height and high intake flow have led to a very low intake crest elevation, which can affect dam operations due to sediment deposition at the dam. Previous sedimentological studies did not take into account two tributaries with significant sediment yields. A re-evaluation of present reservoir capacity, taking into account the additional tributaries and more recent sediment monitoring data, indicates that the sediment deposits at the dam will not reach the intake crest during the projected life expectancy of the Porto Primavera Dam and Reservoir. However, it is clear that a soil conservation plan could substantially extend the utility/life expectancy of the facility.