American Pictures/ Tony Morrison
Itaipú dam, a joint project of Brazil and Paraguay, is on the River Paraná.
Construction began in 1975 and at its peak 30,000 workers were on site. The first
two generating units were running by 1985, by 2005 18 were in operation, and a
further two will be added. One of the world's largest dams, Itaipú is 196m
high, 7.76 km long, and the lake formed by the dam is 170 km long and contains
29 million tonnes of water.