On the basis of the average annual flow, the greatest waterfall in the world is the Boyoma Falls in The Congo (former Zaire), with 17,000 m³/sec (600,000 ft³/sec). The flow of the Guaira (Salto das Sete Quedas) on the Alto Parana River between Brazil and Paraguay had on occasions in the past attained a rate of 50,000 m³/sec (1,750,000 ft³/sec). However, the closing of the Itaipu dam gates in 1982 ended this claim to fame.