Orinoco River

Orinoco River

The Orinoco is a river in South America, one of the continent’s largest rivers. The Orinoco River flows through several countries, including Venezuela and Colombia, and also washes the shores of Brazil. Its total length is about 2,140 kilometers.

The Orinoco is one of the most important rivers in South America and is of great importance to the ecosystem and the local people. The river and its tributaries are a source of drinking water, a means of transportation, and provide food and habitat for many plant and animal species, including rare and unique ones.

The Orinoco, in the languages of almost all the Indian tribes of the basin, translates simply as “River,” as its proper name, with reverence. And this means that it is both “great” and “great,” as this translation is sometimes extended. The Warao Indians, who live in the Orinoco Delta, call it “the river into which you can load an oar,” that is, “a navigable river,” and their self-name means “boat people. This is also what the Guajiro Indians call the Orinoco. How long ago people began settling on the shores of the Orinoco is still not fully elucidated, there is only one evidence that they lived here at least three thousand years ago – it is the rock paintings of the Arawak Indians on the border of Venezuela and Colombia, passing along the river.


The Orinoco begins with a fast stream in the Venezuelan state of Amazonas, near the border with Brazil, on the slopes of Mount Dilgado Chilbaud of the Serra Parima range of the Guiana Plateau. From it and the spurs of the Andes to the west, numerous rivers flow into it, and the Orinoco current is rapidly gaining ground in the upper reaches. Rounding the Guiana Highlands, before flowing into the Meta River, the Orinoco passes through many rapids and rapids, the most important of which are Maipures and Atures. In some places in the upper Orinoco, low waterfalls, up to 17 meters, are formed. Descending from the heights of the highlands, the river flows through the lowlands of Guiana, expanding to 3-10 km. In the gorges, called Angosturas (trenches) in Venezuela, the Orinoco channel narrows to 250 m in some places. Below the largest port of the river – Ciudad Bolivar – its bed expands sharply, and near the town of Barrancas it branches off, forming a complex network of water channels and oxbows, poured between the plots of land overgrown with dense, wet jungle and mangroves. Numerous lagoons and swamps adjoin them. This network forms 36 arms stretching over a large area. Boca Grande, the most important of them, is up to 20 km wide, while the Macareo is the most navigable. These two natural channels flow into the Gulf of Paria of the Atlantic Ocean, while most of the other arms flow into the Boca del Serpiente Strait, between the continent and the island of Trinidad.


When Christopher Columbus saw the Orinoco Delta on August 1, 1498, on his third expedition to the New World, he called it “the river of paradise,” and he is understandable.
The Warao Indians, who still live in the delta today, were friendly to the newcomers, but the Spaniards had no time for them: obsessed with the desire to find El Dorado, they were sure that their dream country was somewhere near. They encountered nothing similar and took their frustration out on the same waraos, destroying their villages. For a very long time the Orinoco was considered in Europe the most mysterious river in South America. Its source was discovered only in 1951, but the delta was explored in the XVI century. In 1531 the conquistador Diego de Ordas went from the mouth of the Orinoco to the Meta River in search of El Dorado, which was, incidentally, the first such deep penetration of the European deep into the South American continent. In the same year the delta was explored by the German expedition of Ambrosius Ehinger. The great journey along the Orinoco and its tributaries was made by the governor of Trinidad, Antonio de Berrio. The first real scientific study of the Orinoco was made by the founder of the geography of vegetation, Alexander Humboldt, who described both the features of the river and its flora and fauna; he was also the first to describe the river pink dolphin.


The natural world of the delta is extremely rich and colorful. The sky is striving tall palms, fruit trees are hung with ripe fruit, orchids bloom under their canopy, bromeliads and other marvelous tropical plants, spread their powerful feather-like leaves and arboreal ferns. Jaguars, ocelots, capuchin monkeys, giant otters, manatees, hundreds of bird species, as well as anacondas, caimans and crocodiles live here.

The life cycles of the river are directly related to the wet and dry seasons. During the rainy season, the Orinoco’s water rises 8-10 meters and vast expanses of water form in the lowlands, and when the water recedes, many small Orinoco tributaries turn into chains of small enclosed swamps, immediately infested by malarial mosquitoes. Further on, things are even harsher: in the open spaces of the savannah in the middle reaches, the grasses become withered, clouds of dust begin to walk, and some trees even shed their leaves. Not counting delta thickets, only the tropical palm gallery forests of the southwestern Llanos Orinoco, stretching parallel to the watercourse, remain fully intact during the drought. Then, of course, there are the savanna cacti.

The avian world of the savanna is as diverse as that of the delta area, with many species of ibis, herons, storks, flamingos and other wading birds, wood ducks, as well as parrots, hawks, kites, falcons and vultures. In savannahs there are a myriad of insect species, and large colonies of termites are often found as well.

And the main predators, just as in the delta, are jaguars, cougars and ocelots. All in all, counting all species of fish, crustaceans, birds, reptiles and mammals living in the Orinoco basin, we can talk about many hundreds of species. And all this rich fauna, judging by the fact that the drought does not cause much damage to its numbers, is perfectly adapted to the extremes of the local climate. It’s humans that do the damage. The Orinoco crocodile, the rarest of the reptiles, is today listed in the Red Book. Only 250 individuals of this endemic of the Orinoco are left, because poachers have killed it for its beautiful pelt. Several dozen other mammal species are on the verge of survival, and for the same reason.


On the banks of the Orinoco live most of the indigenous population of Venezuela. They are Indians of relatively numerous tribes (from 10 to 30 thousand people): Tamanuca, Guayacho, Maquiritare, Yaruro, Yanomami, Warao, Guajiro (this tribe also lives on Lake Maracaibo); mestizos, people of European type – a small number. The growth of towns and ports in the Orinoco Basin began about the middle of the 20th century, when iron ore and other minerals began to be mined in the Guiana highlands, but as a rule all these towns, standing on high ground for protection against flooding, are small. The largest town in the Orinoco Basin is Ciudad Guayana at the confluence of the Orinoco and the Caroni, it was established in 1961 at the Macagua Hydroelectric Plant and the Guri Reservoir, and stretches 40 km. With a population of more than 900,000, it includes two cities: the old San Felix (founded in 1576) and the new Puerto Ordas (founded in 1952).

There are plantations of crops and pastures on the Llanos Orinoco, but even today the area is not so large that it is possible to talk about serious economic development of these expanses by man. With the exception of oil extraction in the oil-bearing, or, in the scientific sense, bituminous, sands of the Orinoco Belt, in which oil is contained in the form of oil shale. Specialists call such oil “unconventional”: its carriers require processing at the initial stage of their production. In 2011. OPEC announced that Venezuela, thanks mainly to the bituminous sands of the “Orinoco belt” (previously they were not very much considered), became the world leader in oil reserves. A year later the same position was confirmed by BP: as of December 31, 2011. Venezuela had 296.5 billion barrels of proven oil reserves, or 17.9% of its total world reserves, while Saudi Arabia, which has for many years been the world record holder in terms of oil reserves, had 265.4 billion barrels on the same date.

General Information

  • One of the largest rivers in South America and the northernmost major river on the continent. It flows mainly in Venezuela, partly along the Venezuelan-Colombian border.
  • It comes from Mount Delgado Chilbaud (highlands of Guiana), at an altitude of 1,047 m. The river has its source in the Bay of Paria Atlantis, where it flows from the Columbia River.
  • Mouth: Gulf of Paria in the Atlantic Ocean.
  • Feeding: mainly rainwater.
  • Major tributaries: right – Ventuari, Caura, Caroni, left – Guaviare, Vichada, Meta, Arauca, Apure.
  • Major cities and ports: Ciudad Guayana, which includes San Felix and Puerto Ordas, Ciudad Bolivar, Santa Barbara, Puerto Ayacucho.
  • Largest reservoir: Guri (on the Caroni River).
  • Nearest airports: Caracas – Simon Bolivar International Airport; Ciudad Guayana – Manuel Carlos Piar Airport; Ciudad Bolivar – Ciudad Bolivar-Thomas de Jerez Airport.
  • Length: 2,736 or 2,410 km (different data).
  • Maximum width (during the spill): 22 km.
  • Maximum depth: 100 m.
  • Water flow rate: 30,000 m3/s (varies from 5-55,000 m3/s depending on the season).
  • Annual runoff: about 915 km3.
  • Area of the basin: 1,086,000 km2. 76.3% of it belongs to Venezuela, the rest to Colombia.
  • The area of the delta: 41,000 km2.
  • The total length of the Orinoco basin shipping routes: about 12,000 km.


  • Natural resources of the Orinoco basin: oil, gas, gold, iron ore, manganese, nickel, vanadium, chromium, bauxites, gold and diamonds.
  • Industries: ferrous and non-ferrous metallurgy (aluminum smelting), pulp-and-paper and food industries in Ciudad Guayana. Cascade of hydroelectric power plants on the Caroni River of the Orinoco basin with reservoirs that provide 76.3% of Venezuela’s electricity needs.
  • Agriculture: cattle breeding, cultivation of cassava, maize, cotton and rice.
  • Fishery.
  • Shipping: vessels of 8 t displacement reach from the mouth to Ciudad Bolivar (435 km from the mouth), lighter vessels during the Orinoco flooding – to Puerto Ayacucho (1127 km).
  • Services: eco-tourism.

Climate and weather

  • Tropical.
  • Rainy seasons last on average from April to October, dry from November to March. In the northern Orinoco Plain, where the northeastern trade winds enter first, the dry season lasts longer and the rainy season lasts only three summer months.
  • Throughout the year, temperatures do not drop below +20°C.
  • The average temperature even in the coolest months of the dry season is +25 ° – +26 ° C, and at the beginning and end of the rainy season it reaches +29 ° C.
  • The average annual rainfall is 800 mm in the north of the Orinoco Plain and up to 1,000 mm in the south.


  • Angel Falls (in Venezuela, they are called Querepa-Cuqui Meru) on the Carrao (Churun) River, which flows into the Apure, one of the largest left tributaries of the Orinoco, the highest waterfall in the world (979 m, according to some sources – 1054 m, the free water fall height – 807 m). Canaima National Park, where the waterfall is located, and the waterfall itself are listed as a UNESCO World Natural Heritage Site.
  • A network of plateaus of different heights of the Gran Sabana (Great Savannah) between the Lemma and Carrao rivers, near the city of Ciudad Guayana (on the territory of the Gran Sabana is Canaima National Park).
  • Ciudad Bolívar: The Angostura Bridge (1967) in the city of Ciudad Bolívar. Length – 1678 m, the height of the supporting towers – 119 m. For some time after its opening it was considered one of the most outstanding technical structures in South America. Colonial architecture; the Cathedral; the Museum of Contemporary Art named after Jesus Rafael Soto, the famous creator of the style of kinetic sculpture and painter, a local native, with a collection of his works; in the city airport – the plane “Flamingo” of James Aingel, who in 1933 flew over Angel Falls and thus discovered it to the world. The waterfall was named after him, although it was Ernesto Sanchez La Cruz who first visited it in the early 20th century.

Fun Facts

  • The Casiquiare River, which branches off from the Orinoco (a phenomenon in which the riverbed divides into two parts, called a bifurcation), flows into the Rio Negra, one of the tributaries of the Amazon. This forms a natural channel linking the Amazon and the Orinoco.
  • The electric eel, a fish native to Orinoco waters capable of generating a discharge of up to 1,300 V and up to 1 A, grows up to 2.4 meters long and weighs up to 19 kilograms. Needless to say, an encounter with this fish can cost the life of both man and horse? The Orinoco catfish, which the Indians call the kuyu-kuyu, can reach a meter in length and 18 kilograms in weight. This fish has spurs at the back of its body that support its tail fin, which makes it look like a prehistoric fish.
  • In 1532, when the conquistadors attacked a warao village, they used environmental weapons. These were red-hot frying pans with hot red pepper powder poured on them. The pungent smoke made the Spaniards sneeze, cough, tears welled up in their eyes, and they and their rifles were powerless against the tomahawks of the Indians.
  • Jules Verne has a novel, The Magnificent Orinoco (1894), about the adventures of several Frenchmen on the river itself and in the jungle.
  • The city of Ciudad Bolivar, which until 1846 was called Santo Tomé de Guayana de Angostura del Orinoco, adopted the Venezuelan Constitution of 1811, written by Simon Bolivar (1783-1830), leader of the Venezuelan and several other revolutions, after whom the city was renamed.
  • The Indians say that several small tribes still live at the source of the Orinoco, avoiding all contact with the outside world.
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