The Paraná River (from Tupi para: "sea" and na: "looks like or as," meaning "that resembles the sea" or "like the sea") is the main forming river of the Plate Basin. When considered in its total length until the mouth of the River Plate, in Buenos Aires, it is the eighth largest river in the world with 4,880 km extension – – and the largest in South America after the Amazon. It is also the tenth largest in the world in flow, draining much of South-Central South America, including part of five states of Brazil. Its river basin covers more than 10% of the Brazilian territory.
Two major rivers – Grande and Paranaiba, which drain part of the water from the states of Goias, Minas Gerais, and Sao Paulo forming the Paraná River from their confluence. Tiete, Paranapanema and Iguaçu rivers are its main tributaries, all in the left bank. The Parana River, in its upper stretch, limits the states of São Paulo and Mato Grosso do Sul. Until its incursion into Argentine territory, four hydroelectric power plants-Jupia, Ilha Solteira, Porto Primavera, and Itaipu bar its course.
In its path, just after the confluence with the River Paranapanema, Parana also waters the state of same name. It limits the border between Brazil and Paraguay for 190 km further downstream, to the mouth of the Iguaçu River, exactly where Itaipu Reservoir was formed.
In this stretch, it is worth noting a sub-basin of high interest to Itaipu, which drains part of the hydrographic network of the Parana state territory directly to its reservoir: the Parana River Basin III. It has 8,000 km2 and encompasses all or part of 28 municipalities in the state.
The Parana River from Foz do Iguaçu becomes the natural boundary between Paraguay and Argentina. At the confluence of the Paraguay River, the river passes to water exclusively Argentine lands, draining into the River Plate, naming this important basin. When receiving also the waters of the Uruguay River, forms the fourth basin of the world: the Plate basin, with 3,190,000 km2.
Paraná River - Permanence of Inflow to Itaipu
The regulation upstream permits flows greater than 8,000 m³/s ninety percent of the time.
Regulated inflow monthly average to Itaipu - Period 1983 to 2011
Drainage Basin (km²)
| Up to the confluence with the Paranapanema River |
673,000 |
| Incremental (from the confluence to the dam) |
147,000 |
| Total |
820,000 |
Lenght of the Paraná River/Prata River (km)
| Paranaíba |
1,200 |
| Confluence of Paranaíba and Grande rivers up to Guaíra |
500 |
| Guaíra up to the mouth of th Iguazu River |
190 |
| Mouth of the Iguazu River to the Paraguay River confluence |
690 |
| Mouth of the Iguazu River up to the Prata estuary |
1,720 |
| Total |
4,300 |
Weather (in the drainage basin)
| Average annual rainfall (mm) |
1,400 |
| Average annual evaporation (mm) |
1,200 |
Weather (on the power plant area)
| Mean annual rainfall (mm) |
1,650 |
| Mean annual evaporation (mm) |
1,000 |
Mean annual temperature (Cº) 22
| Maximum ambient temperature (Cº) |
40 |
| Minimum ambient temperature (Cº) |
-4 |
Flows in the Influence Watershed (from January 1983 to December 2011)
Monthly mean at Itaipu (m³/s)
| Maximum – June 1983 |
33,064 |
| Minimum – August 2001 |
6,768 |
Daily mean at Itaipu (m³/s)
| Mean of the period |
11,663 |
| Maximum – June 15, 1983 |
39,790 |
| Mínima – 10 de septiembre de 2001 |
6,082 |
Daily mean at confluence with Iguazu River (m³/s)
| Mean of the period |
13,973 |
| Maximum – May 31, 1992 |
49,240 |
| Minimum – October 9, 1988 |
6,100 |
Monthly mean Iguazu River at the Capanema Station (m³/s)
| Maximum – July 1983 |
12,176 |
| Minimum – August 2006 |
250 |
Daily mean (m³/s)
| Mean the period |
1,871 |
| Maximum – July 10, 1983 |
28,799 |
| Minimum – October 12, 1988 |
134 |
