HYDROGRAPHY OF VENEZUELA: HYDROGRAPHIC BASINS AND RIVERS - GEOGRAPHY - 2025

The hydrography of Venezuela is the vast set of water resources that the country has and is gathered in large rivers, lakes, lagoons and swamps. It also has three hydrographic slopes, such as the Caribbean slope, the Atlantic Ocean slope and the Valencia Lake slope.

Venezuela has 16 large basins also called hydrographic regions, some 250 sub-basins and about 5000 micro-basins. Their characterization and definition is made taking into account the territorial extension they occupy. The main official hydrographic basins are Orinoco, Cuyuní, San Juan and Río Negro, which are located on the Atlantic slope.

View of the Orinoco River

On the Caribbean side are the basins of Lake Maracaibo, the Gulf of Venezuela and the Caribbean coast, made up of the north-western, north-central and north-eastern areas. The seventh is the slope of the Lake of Valencia; This is an endorheic-type basin fed by the waters of the Güigüe, Tapa Tapa, Aragua, Tocorón and Mariara rivers.

Among the country's water resources are the mighty and extensive Venezuelan rivers, some of which are born in Colombia. The Orinoco River is the largest in the country and is the third largest in South America. It is followed by other very long and mighty rivers, such as the Apure, the Caroní, the Caura, the Ventuari and the Catatumbo, among others.

The country's abundant water resources are superficial and underground. The surface waters are drained through more than 1000 rivers, of which 124 have basins with an extension of more than 1000 km².

Watersheds of Venezuela

The hydrographic basins are portions of territory drained and delimited through a natural system of surface rivers. The waters of the basins are formed with the runoff that descends from the mountains or is the product of the thaw.

The water drained from surface rivers and other underground currents gathers in a single channel and is transported to the sea without interruption, although there are cases in which the water does not reach the sea because it is dammed in lakes or lagoons, forming the endorheic basins.

These natural channels that transport water are divided into sub-basins and these, in turn, into micro-basins. The latter are small extensions of territory that are thus divided for scientific purposes.

Classification

Watersheds are classified as:

Endorheic basins

Its waters do not reach the sea and remain stagnant in lakes or lagoons.

Exoreic basins

Its waters are drained by the depression of the territory to the sea or the ocean.

Arreicas basins

Its waters evaporate or filter through the terrain through which they circulate before reaching a drainage network. This type of basin is common in deserts, in Patagonia and elsewhere.

In Venezuela, 85% of the water that is generated each year is done as surface runoff. These are located on the right bank of the Orinoco River and the remaining 15% is generated in the rest of the country.

Venezuelan aquifers

Groundwater or aquifers occupy a total area of ​​829,000 km² and are estimated at about 5,000 million m³ annually. These aquifers are classified according to their potential in:

Aquifers of great potential

Mesa de Guanipa (Anzoátegui state), the south of Monagas state, the Apure plains, Portuguesa, Barinas and the Guárico river system.

Medium potential aquifers

Valley of Caracas and Barlovento.

Aquifers in the process of depletion

Choir and valley of Quibor in Lara.

Water sources

The distribution of the waters in the Atlantic, Caribbean slopes and the endorheic basin of Lake Valencia, is determined by the great mountain ranges of the country.

On the Atlantic slope are grouped the basins of the Orinoco, Cuyuní, San Juan and Río Negro rivers. On the Caribbean side are the basins of Lake Maracaibo and the Gulf of Venezuela. Then there is the basin of the Caribbean coast, made up of the waters of the north-western, north-central and north-eastern axes.

Finally, on the slopes of Lake Valencia -which is an endorheic basin- the waters of several rivers of the Carabobo state converge.

Main river basins

Orinoco Basin

It covers about 70% of the national territory and the eastern part of the Colombian territory. This makes it the largest in the country and the third largest in South America.

It has an area of ​​989,000 km², which is drained by the Orinoco River and its tributaries. Of these, 643 480 km² -which comprise 65% of its basin- are in Venezuela and 35% in Colombia.

Cuyuní river basin

It covers an area of ​​approximately 40,000 km² and is located in the extreme east of the country. It is an important tributary of the Essequibo River, which is located in the claimed area between Venezuela and Guyana. The main tributaries of the Cuyuní river basin are the Yuruari, Yuruán and Venamo rivers.

San Juan river basin

It is located between the Orinoco delta and the Paria river and is made up of the San Juan and Guanipa rivers, which are its largest collectors. It is a basin on the Atlantic slope, whose waters flow to the north of the Orinoco delta.

Rio Negro basin

This basin covers a territorial extension of about 42,000 km² in the part of Venezuela. It is born in Colombia with the Guainía river. It serves as a hydrographic link between the Orinoco river basin and the Amazon river basin, through the Casiquiare river that joins them.

Lake Maracaibo Basin and the Gulf of Venezuela

This exorheic basin is permanently drained by some 150 rivers. It uses the waters that run off the Sierra de Perijá (Zulia) and the high peaks of the Cordillera de Mérida (Los Andes). It has a medium extension but is of great flow.

It covers an area of ​​approximately 80,000 km² between the territories that are located in Venezuela and Colombia. Its main tributaries are the Catatumbo, Santa Ana, Palmar, Limón, Escalante, Chama and Motatán rivers.

Caribbean littoral basin

It is made up of several smaller basins and its territory is divided into three portions or zones: north-west, north-central, and north-east. The basin of the Caribbean coast covers an area of ​​approximately 80,000 km².

Most of its waters come from the Cordilleras de los Andes (extreme north) and the Cordillera de la Costa (including the Eastern Massif).

Valencia Lake Basin

Due to its nature, this basin that forms around the Lake of Valencia has no outlet to the sea. It covers an area of ​​3100 km² through whose territory the waters coming mainly from mountain rivers are drained. Its tributaries are the Güigüe, Tapa Tapa, Aragua, Tocorón and Mariara rivers, in Carabobo state.

Major rivers

Orinoco river

It is the longest river in Venezuela and one of the most important in South America due to its length and flow. It measures 2,140 km in length, but when integrated into the Orinoco-Guaviare system (Colombia) it reaches 2,800 km.

The flow of the Orinoco River is 33,000 m³ / s; This makes it the third largest in the world behind the Amazon and Congo rivers.

It is born in the Amazon state and flows into the Atlantic Ocean, where it arrives forming the Delta Amacuro state. During its journey it crosses the country and its waters flow through the border of Venezuela and Colombia.

The main tributaries of the Orinoco on the left bank are the Arauca River and the Apure River, while on the right bank are the Ventuari, Caura and Caroní rivers, among others.

When meeting the Guaviare river (on the Colombian side) it delimits the territories of Venezuela and Colombia. During its course it is divided into four sections: the upper Orinoco (242 km long), middle Orinoco (750 km), lower Orinoco (959 km) and Delta Amacuro (200 km long)

Within Venezuela it separates the Bolívar state from the Apure, Guárico, Anzoátegui and Monagas states. Its waters form the Delta Amacuro state.

Caroni River

Caroni River

It is the second largest river in Venezuela. It has an immense basin that covers a territory of more than 95,000 km2. With a flow of 4850 m³ / s, it is a river with dark waters, apparently because it houses large deposits of iron in its bed.

It is born in the Kukenán tepui in Bolívar state, but takes its name from where it joins the Yuruari river. It is a high-flow river that flows into the Orinoco, near Ciudad Guayana, and flows through numerous streams and waterfalls.

The most important are the Angel Falls, the highest waterfall in the world at almost 1000 m. fall; and the Kukenán waterfall, another immense waterfall of about 600 m. high (the tenth in the world. They are followed by other smaller but imposing waterfalls, such as the Aponwao, the Torón, the Caruay, La Llovizna, the Cachamay and the Kama-Marú.

Caura River

This other river in the Bolívar state is the third longest and most mighty in the country. It is 723 km long and also flows into the Orinoco River. It is born south of the plateau of Jaua, where it takes the name of Merevari.

Its most important tributary is the Erebato, another high-flow river. It is located between the Cedeño and Sucre municipalities of that Venezuelan entity and its basin covers an area of ​​52,000 km².

Black river

In the Colombian section, the Negro River is called Guainía. This long river located in the Amazonian territory is the one with the greatest flow of the tributaries of the Amazon.

It is also the longest on its left side and the one with the largest amount of sewage on the entire planet. It feeds from the water sources located in the basins of the Amazon River and those of the Orinoco.

Apure River

The Apure River is the largest tributary of the Orinoco River in the Venezuelan plains that reaches a length of 820 km. However, when connecting with the Uribante river - one of its tributary sources that originates in the Andes - its length extends to 1095 km.

This stream of water is born from the confluence of the Sarare and Uribante rivers in the section that is located in the Apure state. The Apure River runs through the Venezuelan plains irrigating this entire region before flowing into the Orinoco River.

Ventuari River

It is a mighty river in the state of Amazonas with a length of approximately 520 km. It is also a tributary of the Orinoco River where it flows into the final section called Delta del Ventuari (although it is not a delta).

The Manapiare River, which is about 400 km long and has a great flow, is its largest tributary. Its basin is approximately 40,000 km².

Portuguese River

It is also called La Portuguesa river (in honor of the wife of one of the founders of Guanare, the capital of the Portuguese state). This river is born in the Andes mountain range, in the vicinity of Biscucuy. It has a length of 600 km until its mouth in the Apure River.

Its basin covers an area of ​​approximately 80,000 km² and its main tributaries include the Acarigua, Morador, Guache and Ospino rivers, as well as the Cojedes, the Guanare, the Boconó and the Tiznados and Pao rivers.

Santo Domingo River

This river is born in the high Andean peaks, in the El Águila peak and in the Mucubají Lagoon, in the state of Mérida, from where it descends to the state of Barinas, making a journey of about 200 km until it converges with the Aracay river.

It is a high-flow river, as it has an average annual volume of 18 billion m³ of water. The Santo Domingo River represents 17% of the volume that flows into the Orinoco on the left bank.

Catatumbo River

This river is born in the department of Norte de Santander, Colombia, in the western part of the department, bordering Venezuela. It empties into Lake Maracaibo, being its largest tributary by providing it with about 60% of the volume of fresh water it receives.

It has a basin of 24,416 km², of which more than 16,600 correspond to Colombian territory and the rest to Venezuela.

Other major rivers

- Uribante.

- Chama.

- San Juan.

- Goal.

- A re.

- Yaracuy River.

- Tocuyo River.

- Neverí.

- Aroa River.

- Cuchivero.

- Manzanares River.

- Suapure.

- Paraguachón River.

- Motatán River.

- Apon.

- Escalante River.

- Lemon.

References

1. List of rivers of Venezuela. Retrieved April 3, 2018 from simple.wikipedia.org
2. Hydrography of Venezuela. Consulted of es.wikipedia.org
3. Major Rivers Of Venezuela. Consulted of worldatlas.com
4. Rivers. Consulted from countrystudies.us
5. Hydrographic basins of Venezuela. Consulted of issuu.com
6. Most Important Rivers of Venezuela. Consulted of goodtasks.com
7. The emblematic river of Barinas: Santo Domingo. Consulted of barinas.net.ve
8. Shapefiles (*.shp) from Venezuela (Base Layers). Consulted of tapiquen-sig.jimdo.com