The Porumbacu (in its upper course also: Valea SÃÂrÃÂÃÂii and Valea Mare) is a left tributary of the river Olt in Romania. It discharges into the Olt in Porumbacu de Jos. The Porumbacu originates on the northern slope of Negoiu Peak, FÃÂgÃÂraÃÂ Mountains. Its length is and its basin size is .