The Caroní River is the second most important river of
Venezuela
Venezuela, officially the Bolivarian Republic of Venezuela, is a country on the northern coast of South America, consisting of a continental landmass and many Federal Dependencies of Venezuela, islands and islets in the Caribbean Sea. It com ...
, the second in flow, and one of the longest, from the
Kukenan tepui
A tepui , or tepuy (), is a member of a family of table-top mountains or mesas found in northern South America, especially in Venezuela, western Guyana, and northern Brazil. The word tepui means "house of the gods" in the native tongue of the ...
through to its confluence with the
Orinoco River
The Orinoco () is one of the longest rivers in South America at . Its drainage basin, sometimes known as the Orinoquia, covers approximately 1 million km2, with 65% of it in Venezuela and 35% in Colombia. It is the List of rivers by discharge, f ...
. The name "Caroní" is applied starting from the confluence of the Kukenan with the Yuruaní River at from the source of the Kukenan and from its discharge in the Orinoco. The confluence takes place in
Bolivar State. The Caroní River is the longest river located entirely within Venezuela.
Hydraulic regime

The Caroní is one of the rivers with the highest discharge rates in the world, with respect to the area of its basin. The average discharge is , with variations caused by the wet/dry seasons. The average maximum discharge is , and the average minimum is . Among the historic extremes are . The Caroní supplies 15.5 percent of the discharge of the Orinoco river. One of the characteristics of the Caroní's water is the dark color, caused by the high amount of
humic acid
Humic substances (HS) are colored relatively recalcitrant organic compounds naturally formed during long-term decomposition and transformation of biomass residues. The color of humic substances varies from bright yellow to light or dark brown lead ...
s due to the incomplete decomposition of the phenol content of the vegetation. The Caroní thus belongs to the
blackwater rivers, as does the
Negro River, or Rio Negro in Brazil, Venezuela and Colombia. In the late 1940s
diamonds
Diamond is a solid form of the element carbon with its atoms arranged in a crystal structure called diamond cubic. Diamond is tasteless, odourless, strong, brittle solid, colourless in pure form, a poor conductor of electricity, and insol ...
were found in the
Caroní basin near the famous ''Lost World Region'' which then was accessible only by aircraft and four wheel drive vehicles.
Basin
The river drain the
Guayanan Highlands moist forests ecoregion.
The Caroní basin covers and is part of the Orinoco basin, the most important river of Venezuela. This means for the two big rivers that they have very similar hydrographic characteristics. The Caroní itself and its tributary the
Paragua are rivers with a ''staircase'', in the sense that many falls and rapids are alternated with stretches with gentle slopes, with many meanders and
oxbow lake
An oxbow lake is a U-shaped lake or stream pool, pool that forms when a wide meander of a river is meander cutoff, cut off, creating a free-standing body of water. The word "oxbow" can also refer to a U-shaped bend in a river or stream, whether ...
s (naturally cut off meanders). Among the most important falls of these rivers and their tributaries are
Angel Falls
Angel Falls (; Pemon: ''Kerepakupai Merú'' or ''Parakupá Vená'') is a waterfall in Venezuela.
It is the world's tallest uninterrupted waterfall, with a height of , and a plunge of . The waterfall drops over the edge of the Auyán-tepui m ...
, with the highest free fall of the world, almost , and Kukenan Falls, the tenth on the world scale with a free fall. Others falls with less height but high volume are the Aponwao, Caruay and La Llovizna waterfalls.
Hydroelectric power
Because of its high discharge rate, with a yearly average of and a steep slope, the Caroni ideally suited for the generation of
hydroelectric energy with four
plants
Plants are the eukaryotes that form the kingdom Plantae; they are predominantly photosynthetic. This means that they obtain their energy from sunlight, using chloroplasts derived from endosymbiosis with cyanobacteria to produce sugars f ...
along its course (
Macagua I, II and III), near its mouth, the
Caruachi, some aback, and lastly the plant of
Guri, in the middle of Necoima or Necuima, some from Puerto Ordaz. This plant has its reservoir, with an area of , in the middle of the river, and has a power of 10,000 MW, and is now the third biggest in the world, after the
Three Gorges Dam
The Three Gorges Dam (), officially known as Yangtze River Three Gorges Water Conservancy Project () is a hydroelectric gravity dam that spans the Yangtze River near Sandouping in Yiling District, Yichang, Hubei province, central China, downs ...
in China (22,500 MW) and the
Itaipu Dam
The Itaipu Dam ( ; ; ) is a hydroelectric dam on the Paraná River located on the border between Brazil and Paraguay. It is the third largest hydroelectric dam in the world, and holds the 45th largest reservoir in the world.
The name "Itai ...
in Paraguay and Brazil (14,000 MW)
National Parks
In the high basin of the rivers that form the Caroni (Aponguao, Cuquenán and Yuruaní) the
Gran Sabana
La Gran Sabana (, ) is a region in southeastern Venezuela, part of the Guianan savanna ecoregion.
The savanna spreads into the regions of the Guiana Shield, Guiana Highlands and south-east into Bolívar, Venezuela, Bolívar State, extending fu ...
is spread out, partly belonging to the
Canaima National Park
Canaima National Park () is a park in south-eastern Venezuela that roughly occupies the same area as the La Gran Sabana, Gran Sabana region. It is located in Bolívar State (Venezuela), Bolívar State, reaching the borders with Brazil and Guya ...
.
Mining
Along the Caroní River between the confluence with the
Icabarú River and San Salvador de Paúl, there are several artisanal gold mines, mainly on the left hand side of the river outside the national park, but a few can also be found on the right hand side inside the
Canaima National Park
Canaima National Park () is a park in south-eastern Venezuela that roughly occupies the same area as the La Gran Sabana, Gran Sabana region. It is located in Bolívar State (Venezuela), Bolívar State, reaching the borders with Brazil and Guya ...
. Besides the devastating effects of logging and deforestation to clear the site for the mines, the far greater danger is the use of mercury which poisons the Caroní river, its fauna and inhabitants living along its shore. High levels of mercury have been found not only in the Caroní river but also in Lake Guri and further downstream. The government of Venezuela pledged to reduce
illegal mining
Illegal mining is mining activity that is undertaken without state permission. Illegal mining is the extraction of precious metals/rocks without following the proper procedures to participate in legal mining activity. These procedures include pe ...
activities with the sustainable development plan for mining from 2016-18.
Illegal mining surged under the government of
Hugo Chávez
Hugo Rafael Chávez Frías (; ; 28 July 1954 – 5 March 2013) was a Venezuelan politician, Bolivarian Revolution, revolutionary, and Officer (armed forces), military officer who served as the 52nd president of Venezuela from 1999 until De ...
, due to the nationalization of mines run by international mining companies and this had the negative consequence of an increase of mercury use as other processes are more difficult and costly to use for illegal,
artisanal mining
Artisanal and small-scale mining (ASM) is a blanket term for a type of subsistence mining involving a miner who may or may not be officially employed by a List of mining companies, mining company but works independently, mining minerals using the ...
.
References
{{DEFAULTSORT:Caroni River
Rivers of Venezuela
Rivers of Bolívar (state)