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Articles from Britannica encyclopedias for elementary and high school students.
- Guaíra Falls - Student Encyclopedia (Ages 11 and up)
Guaira Falls, or Guayra Falls, is the falls at the head of navigation, Alto (Upper) Parana River, between Brazil and Paraguay; the Parana was about 3 miles (5 kilometers) wide at crest of falls and poured over ledge in 18 separate cataracts (highest, 130 feet; 40 meters); combined average flow of these cataracts was far greater than that of Niagara; crest of falls is now below water level of a reservoir created by the dams and spillway of the Itaipu hydroelectric plant (completed 1982, enlarged 2004).