The Tay - see http://209.85.229.132/search?q=cache:rFJo05doNw8J:www.sln.org.uk/geography/Documents/9number/Question%2520of%2520rivers.ppt+volume+of+water+british+rivers&cd=11&hl=en&ct=clnk&gl=uk
The lower course i think...
the Amazon
The Amazon River is the greatest river in South America, both in length (it is in fact, the longest in the world at approx. 4,000 miles or 6,400 km) and volume, with an average discharge greater than the next seven most voluminous rivers in the world... combined.
The Amazon River has the highest volume of water flow.
beacause the water can hold it
The Amazon in South America has the highest volume of water.
it is the amazon river in south America
River Congo
465
465
The river that holds the most water in the world is the Amazon River even though the Nile is the longest river in the world.
A river stage with high flow velocity and volume, such as during flood events, typically causes the greatest amount of erosion. The force of the water carrying sediment and debris can lead to significant erosion of riverbanks and the riverbed.