Answer :
The Grand Coulee Dam is said to be the largest concrete dam. Currently the world’s largest
concrete dam is the Itaipu Dam, an accomplishment of two neighboring countries, Brazil and
Paraguay in South America.
Though it is not finished yet, the Three Gorges (or Sandapong) Dam on the Yangtze River in
China will take over as the largest upon its completion, which is slated for 2009.