Greatest Places Physical Geography: Dr. Cecil Keen, July 1997

Iguazu Falls

Geographic Description: From its source in the Serra do Mar, not far from the Atlantic coast, the Rio Iguazu (or Iguassu) flows westward for about 820 miles across southern Brazil. Gathering tributaries, the river grows steadily in volume as it meanders across the uplands of the Parana Plateau. Step by step it makes its way toward sea level, tumbling over some 70 waterFalls that interrupt its course. One of them, Nacunday Falls, has a drop of 131 feet, nearly that of Niagara Falls.

But the river takes its grandest leap just a short distance above its confluence with the Parana, where the Iguazu forms a boundary between Argentina and Brazil. Plunging at last off the edge of the plateau, the river thunders down in what one observer likened to the "awesome spectacle of an ocean pouring into an abyss." The thunderous roaring of the water can be heard from miles away.

Strung out along the rim of a crescent-shaped cliff about 2.5 miles long is a series of some 275 individual cascades and waterFalls separated by rocky, densely wooded islets. Some of the cascades plummet straight down for 269 feet into the gorge below. Others are interrupted by ledges and send up clouds of mist and spray, creating a dazzling display of rainbows.

The Falls, which would be memorable in any setting, are made all the more beautiful by their lush surroundings. The luxuriant forests are filled with bamboo, palms, and delicate tree ferns. Brilliantly feathered parrots and macaws flit through the foliage, competing for attention with the exotic blooms of wild orchids, begonias, and bromeliads.

The Falls are at their best during the rainy season from November to March. The flow slows down during the rest of the year, sometimes drastically. In May and June of 1978 the Falls dried up completely for 28 days, the first time such a thing had happened since 1934. But, normally, Iguazu is a dependable, ever-changing spectacle throughout the year.

The name Iguazu simply means "great waters" in the local Indian language. According to legend, the great waterfall was created in an outburst of rage by the god of the Iguazu River, who lived in a particularly wild and violent area of the downpour called the Garganta do Diablo (Devil's Throat). The Falls are close to the point where the Iguazu and the Parana rivers join and the boundaries of Brazil, Argentina, and Paraguay converge. The countries are linked by two bridges: the Amizada (Friendship) Bridge between Brazil and Paraguay, and the Tancredo Neves Bridge between Brazil and Argentina.

Other Local Features:

Itaipu Dam: The most powerful hydroelectric plant in the world has harnessed the waters of the Mother of the Sea.

The Parana River (the name means Mother of the Sea) rises in Brazil and has a total length of more than 3000 miles. It runs southwest to the town of Guaira, and for 118 miles it forms the border between Brazil and Paraguay running down to the Iguazu Falls and the point where Brazil, Paraguay and Argentina all meet. The Parana forms the border between Paraguay and Argentina, for a stretch, and then flows south across Argentina to Buenos Aires, and the Rio de la Plata (Plate River).

The Itaipu Dam, a monster concrete dam (five times the size of the Aswan High Dam) is 12 miles north of Foz do Iguazu. The dam is almost five miles long and rises to a height of 738 feet, or the height of a 75-story building. The river at this point is 1,300 feet wide and 200 feet deep. A canal 1.25 miles long and 490 feet wide was blasted and hewn out of the rock to divert the river while the dam was being constructed. This was ready in 1978. The riverbed dried out, and the building of the dam began in January 1979. The power station's generators are the largest in the world, rated at 700,000 kilowatts each, and in total rate at 12.5 million kilowatts--the highest figure for a single power plant in the world. The dam has created a lake covering an area of 520 square miles.

Archaeological remains dating as far back as 8,000 years ago were rescued from some 300 sites before the inundation began, and thousands of animals were caught and then released in nature reserves on the banks of the lake, where 20 million trees have been planted. The Itaipu Dam and Iguazu Falls attract more than 1 million visitors a year.








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