Paraná River

"This article is about the second-longest river in South America: For the shorter river in Goiás, central Brazil, see Paranã River"

The Paraná River ("Río Paraná" in Spanish, "Rio Paraná" in Portuguese) is a river in south central South America, running through Brazil, Paraguay and Argentina over a course of some 2,570 kilometers (1,600 miles). This length increases to 3,998 km (2,484 miles) if the distance is counted from the headwaters of the Paranaiba River in Brazil. It is considered second in size only to the Amazon River among South American rivers. The name Paraná comes from the Tupi language and means "like the sea" (that is, "as big as the sea").

Course

The Paraná River is formed at the confluence of the Paranaiba and Grande rivers in southern Brazil. From the confluence the river flows in a generally southwestern direction for about 619 km (385 miles) before encountering the city of Saltos del Guaira, Paraguay. This was once the location of the Sete Quedas waterfall, where the Paraná fell over a series of seven cascades. This natural feature was said to rival the world famous Iguazu Falls to the south. The falls were flooded, however, by the construction of the Itaipu dam, which began operating in 1984.

For the next approximately 190 km (125 miles) the Parana flows southward and forms a natural boundary between Paraguay and Brazil until the confluence with the Iguazu River. Shortly upstream from this confluence, however, the river is dammed by the impressive Itaipu dam, the largest hydroelectric power station in the world, and creating a massive, shallow reservoir behind it. After merging with the Iguazu, the Paraná then becomes the natural border between Paraguay and Argentina. The river continues its general southward course for about 468 km (291 miles) before making a gradual turn to the west for another 820 km (510 miles), and then encounters the Paraguay River, the largest tributary along the course of the river. Before this confluence the river passes through a second major hydroelectric project, the Yaciretá dam, a joint project between Paraguay and Argentina. The massive reservoir formed by the project has been the source of a number of problems for people living along the river, most notably the poorer merchants and residents in the low lying areas of Encarnación, a major city on the southern border of Paraguay. River levels rose dramatically upon completion of the dam, flooding out large sections of the cities lower areas.

From the confluence with the Paraguay River, the Paraná again turns to the south for another approximately 820 km (510 miles) through Argentina, making a slow turn back to the east near the city of Rosario for the final stretch of less than 500 km (310 miles) before merging with the Uruguay River to form the Río de la Plata and emptying into the Atlantic Ocean. During the part of its course, downstream from the city of Diamante, Entre Ríos, it splits into several arms and forms the Paraná Delta, a long flood plain which reaches up to 60 km in width.

Uses

The Rio Paraná along with its tributaries creates a massive watershed that spreads throughout much of the south central part of the continent, essentially encompassing all of Paraguay, much of southern Brazil, northern Argentina, and even reaching into Bolivia. If the Uruguay River is counted as a tributary to the Paraná, this watershed extends to cover much of Uruguay as well. The volume of water flowing into the Atlantic Ocean through the Río de la Plata is roughly equal to the volume at the Mississippi River delta. This watershed services a number of large cities, including São Paulo, Buenos Aires, Asunción and Brasília.

The Paraná and its tributaries are a source of income and even daily sustenance for a number of fishermen who live along its banks; some fish species (such as the surubí and the sábalo) are commercially important and exploited for massive internal consumption or for export.

Much of the length of the Paraná is navigable and is used as an important waterway linking inland cities in Argentina and Paraguay to the ocean, providing deep water ports in many of these cities. The construction of massive hydroelectric dams along the river's length has blocked its use as a shipping corridor to cities further upstream, but the economic impact of those dams is considered to offset this. The Yacyretá and Itaipú dams on the Paraguay border have made the small, largely undeveloped nation the world's largest exporter of hydroelectric power.

Links across the Paraná

The Argentine course of the Paraná is crossed by the following bridges, beginning upstream:

*The Friendship Bridge links Ciudad del Este, (Paraguay) and Foz do Iguaçu, (Brazil) and, though not passing over Argentine waters, the bridge is critical for the Triple Frontier area these cities share with Puerto Iguazú, Argentina.
* San Roque González de Santa Cruz Bridge, between Posadas, capital of Misiones Province, Argentina and Encarnación, Paraguay, capital of the Paraguayan department of Itapúa
* General Belgrano Bridge between Resistencia (capital of Chaco) and Corrientes (capital of Corrientes).
* Hernandarias Subfluvial Tunnel, which runs under the river between Santa Fe (capital of Santa Fe) and Paraná (capital of Entre Ríos).
* Rosario-Victoria Bridge between Rosario, Santa Fe, and Victoria, Entre Ríos.
* Zárate-Brazo Largo Bridge between Zárate, Buenos Aires and the Province of Entre Ríos.

Additionally, a bridge between Reconquista, Santa Fe and Goya, Corrientes is under study. Also, as recent as 1998 there were joint studies carried out by the governments of Uruguay and Argentina for the construction of a bridge between the two countries over the Río de La Plata estuary, the exact location was not decided.

External links

* [http://earthtrends.wri.org/maps_spatial/maps_detail_static.cfm?map_select=425&theme=2 Information and a map of the Paraná's Watershed]