Río de la Plata

Río de la Plata (Spanish pronunciation: [ˈri.o ðe la ˈplata], River of Silver)—sometimes rendered River Plate in British English and the Commonwealth, and occasionally rendered [La] Plata River in other English-speaking countries—is the river and estuary formed by the confluence of the Uruguay River and the Paraná River on the border between Argentina and Uruguay. It is a funnel-shaped indentation on the southeastern coastline of South America, about 290 kilometres (180 mi) long.

The Río de la Plata widens from about 2 kilometres (1.2 mi) at the inner part to about 220 kilometres (140 mi) at its mouth. It forms part of the border between Argentina and Uruguay, with the major ports and capital cities of Buenos Aires and Montevideo on its southwest and northeast shores. The coasts of the Río de la Plata are the most densely populated areas of Argentina and Uruguay.

Geography

Some geographers consider the Río de la Plata a gulf or marginal sea of the Atlantic Ocean, while others consider it a river. For those who regard it to be a river it is the widest in the world, with a maximum width of about 220 kilometres (140 mi) and a total surface area of about 35,000 square kilometres (14,000 sq mi).

The Río de la Plata behaves as an estuary in which freshwater and seawater mix. Its freshwater comes from the Paraná River, one of the world's longest, and its main tributary, the Paraguay River, as well as the Uruguay River and other smaller streams. Currents in the Río de la Plata are controlled by tides reaching to its source and beyond, into the Uruguay and Paraná rivers.Both rivers are tidally influenced for about 190 kilometres (120 mi). The tidal ranges in the Río de la Plata are small, but its large width allows for a tidal prism important enough to dominate the flow regime despite the huge discharge received by the tributary rivers. The rivers discharge is strong enough to prevent salt water from penetrating the inner Río de la Plata.

A submerged shoal, the Barra del Indio, acts as a barrier, separating the Río de la Plata into an inner freshwater riverine area and an outer brackish estuarine area.The shoal is located approximately between Montevideo and Punta Piedras (the northwest end of Samborombón Bay). It is the freshwater of the inner area that causes many to describe the Río de la Plata as a river. The depth of the inner fluvial zone is between about 1 to 5 metres (3.3 to 16 ft). It is about 180 kilometres (110 mi) long and up to 80 kilometres (50 mi) wide. The depth of the outer estuary zone increases from 5 to 25 metres (16 to 82 ft).

Drainage basin

Satellite image of the Parana and Uruguay rivers emptying into the Río de la Plata. Due to the relatively calm surface of the estuary and the angle of the Sun relative to the satellite, the current of the river flowing out into the Atlantic is visible.

The La Plata Basin, the Río de la Plata's drainage basin, is the second largest in South America. At a size of about 4,144,000 square kilometres (1,600,000 sq mi), the basin is about one fourth of the continent's surface. It includes areas of southeastern Bolivia, southern and central Brazil, the entire nation of Paraguay, most of Uruguay, and northern Argentina. The main rivers of the La Plata basin are the Paraná, one of the longest in the world, and its main tributary, the Paraguay River, and the Uruguay River.

The Paraná RIver's main tributaries include the Paranaíba River, Grande River, Corumbá River, Tietê River, Paranapanema river, Iguazu River, Negro River, Carcarañá River, Gualeguay River, and the Salado River. The Paraná River ends in the large Paraná Delta.

The Paraguay's main tributaries include the Jauru River, Cuiabá River, Taquari River, Nabileque River, Curiche Grande River, Apa River, Pilcomayo River, and the Bermejo River. The Paraguay River flows through the Pantanal wetland.

The Uruguay's main tributaries include the Pelotas River, Canoas River, Peperiguaçu River, Ibicuí River, Quaraí River, and the Río Negro.

Battle of the River Plate

The Battle of the River Plate, an early World War II naval engagement between the German pocket battleship Admiral Graf Spee and British and New Zealand ships, started several miles off the coast of the estuary. The German ship retired up the estuary and put into port at Montevideo. A few days later, rather than fight outgunned, she was scuttled in the estuary.

These events were depicted in the 1956 British film The Battle of the River Plate – also known as The Pursuit of the Graf Spee – by Michael Powell and Emeric Pressburger.

Etymology

The English name "River Plate" is not, as sometimes thought, a mistranslation, as "plate" was used extensively as a noun for "silver" or "gold" from the 12th century onwards, especially in Early Modern English and the estuary has been known as the River Plate or Plate River in English since at least the time of Francis Drake. A modern translation of the Spanish Río de la Plata is "Silver River", referring not to color but to the riches of the fabled Sierra de la Plata thought to lie upstream.

The English version of the name served as an inspiration for one of Argentina's most important football clubs, Club Atlético River Plate.

Fauna

The Río de la Plata is a habitat for the Loggerhead Sea Turtle, Green Sea Turtle, Leatherback Sea Turtle, the rare La Plata Dolphin, and many species of fish.