In these areas of southern Venezuela we will observe the consequences of erosion, caused by the very high rainfall that characterizes the region and together with other natural agents, helps shape the landscape. The precipitation per year with an average of 3,250 mm, giving the case in some places where the annual average was 4,000 mm, and in the mouth of the river or the Arm Ocamo Cassiquiare. This should not speak properly dry season because only north of the state is where there are three months with low precipitation of 70 mm on average.
The major rivers of the basins covered are: Orinoco Ventuari or Ventuario, Sipapo Guanía-Black River and the special case Cassiquiare Arm.
The Orinoco River father (Uriaparí, Baraguá, Baraguan, Ibinoco), is the collector of nearly all the rivers of Venezuela and through him lead directly to the Atlantic waters, especially the Amazonas state, but here another portion of tributaries are to Guanía-Black River and carry their waters to the giant Amazon. There are two well-defined basins, but by Cassiquiare our giant Orinoco also pays tribute to its waters. The Cassiquiare turn receives in its course several navigable rivers Large volume Pamoni, Passive, Siapa Pasimoni.
In the far SE is the sources of the Orinoco, on the hill Chalbaud to 1,047 mt. altitude. Sierra Parime borders with Brazil, 2 º 19 '05.7'' North latitude and 63 º 21' 42.6'' West longitude, according to the Gral.F. Risquez Iribarren, who discovered the 27/11/51 front of Expedition Venezuelan Franco, remembering that after a second source was discovered 16 km. Further north, according to official information from the Boundary Commission Venezuela-Brazil. We take Shaili.ko, Dr. Paul J. Anduze, page 410:
"One of the Venezuelan Commission members Mr. Jorge Panchenko, accompanied by five men, one who raised two rivers that form the Orinoco River. He found that for the source stream runs north from its inception and throughout its course on a bed of coarse sand and small beaches form. Its waters are crystal clear and do not contain suspended solids, or colors, as in other waterways in the region. The altitude of the source is of 1,144 mt. 0 '. "
"The source of the Orinoco River South, already explored in 1951, has a very different look to the north. In effect she runs in the first kilometers on a muddy throat with fetid emanations and its bed is poorly defined. Suddenly, after a run of just two kilometers, the aspect changes to make the characteristics of the North and is only source at the confluence where rediscovers training ground vegetation and muddy. "
The course divides Orinoco and Amazonas State in Venezuela by a diagonal axis SE to NE and from its source to its mouth in the Atlantic monstrous through a large delta, which gives its name to Delta Amacuro. It forms a great arc so pronounced that their sources come from close meridian of Ciudad Bolivar. Get to Atlantic after covering the course of 2,800 miles away. Get over 2,000 streams and this volume is being considered as the fifth largest river in the world. The average flow volume or year in Boca Grande is 35,000 cubic meters per second and in the rainy season are estimated 100,000 cubic meters per second, compared to Barrancas. For the length of your course is ranked as the ninth planet.
The Orinoco basin covers most of the country's river system calculated its surface in 850,000 km2, approximately near the land surface.
The Orinoco basin covers most of the country's river system, calculating its 850,000 km2 surface. Approximately slightly smaller than Venezuela. It looks like a giant arm clothing throughout the South or Guiana Shield, excluding sub. Apure River basin. According to calculations it is estimated that the Orinoco near its mouth and before partition into the arms of the Delta, poured annually into the Atlantic Ocean 400 million metric tons of valuable alluvial, rich in various minerals. On this point could be very interesting studies.
During the rainy season, in the months June and July, the Orinoco beyond its borders, flooding thousands of km2, forming huge overflows and lagoons. In this rainy season are hardly powerless camping dry parts when navigating rivers. In contrast, in the dry season, the landscape changes completely: recur ravines and beaches, islands widen, emerge dry rocks and some Cañitos, become ways. Some disappear fast rapids and water flow be cut by rocks, but instead other speed increase when between these boulders and rocks very hilly, water slides unstoppable. It is true that large vessel navigation is difficult, but the landscapes are more beautiful by the huge clean sandy beaches and rocky rare and suggestive forms that emerge across the river. And the talk here about our Orinoco, we can say equally large rivers. The landscapes and aspects completely change from winter to summer, and also change slightly the activities of the inhabitants, according to the facilities and possibilities given the nature for their survival. During the summer abundant fishing and hunting is facilitated practiced as a means of subsistence, survival, also facilitates the exploitation of certain forest products.
This river should be split better in Alto Orinoco from birth to fork Cassiquiare middle Orinoco from this bifurcation until Atures and lower Orinoco from Atures to its mouth by the great Delta.
Within the state, this great river receives most of its tributaries on the right bank, some of which are true sub watersheds. For this we have the largest margin: Potomao, Manaviche, Ocamo, Padamo, Iguape, Cunucunuma, Guanamé, Puruname, Yagua Ventuari, IBOA, Sipapo Cataniapo, Parhueña.
As for the left bank tributaries we write: Ugueto, Gobber, Mavaca, Ydije, Cabirima, Atabapo, plus Colombian rivers Guaviare, Zama, Matabeni, Vichada, Tomo, Tuparro Plateau.
To complete the list of the major rivers of this entity, we have Black Guainia-River North-South course, which by its Venezuelan bank receives the streams and rivers Pimichin, San Miguel, Tiriquín, Guape, Columbus, almost all navigable. But as a special case should be the channel or arm Cassiquiare that shedding Orinoco empties into the Guanía, which will start from here called Black River. Its main tributaries on the left bank fall: Caripo, Pamoni, Pasiba and bigger, the Siapa and Pasimoni, almost all navigable.
Among the major tributaries of the Orinoco is the Padamo, that originating in the high southern flank of Mount Marahuaca in its 135 km. of course, receives the rivers Continamo, Uotamo, Metacuni and other minor, this sub-basin covers about 10,000 km2. But Ventuari, whose source is in the Sierra Parime border with Brazil, is the largest tributary of the Amazon, with a sub-basin of about 50,000 km2. and receives several navigable rivers. You will be divided into High Ventuari from its headwaters to the big jump of 25 mt Tencua. Fall and thence to its mouth in the so-called delta in Lower Ventuari Ventuari. Its course is estimated at 550 km., With half waterway, its largest tributary is the Manapiare, which in its 150 km. of course, the vast waters of the Valleys area of almost 7000 km2 Manapiare. This in turn has the Parucito as the main tributary, the Atababo Apure, a stream in winter; also several pipes. Other important tributaries in the Upper Ventuari we note: Féuete, Antabare, Uajuña, Madadejara, Duck, Uesete, Yatito, Uiue, Axe, in Lower Ventuari: Caño Black, Asita, Camani, Marieta, Paru, Taui-Taui, Marueta, Yureba , Iamara, Yakiguapo, Guapuchí, almost all navigable.
The river runs Atabapo-South-North Temi Franco, forming the border with Colombia. Start with the name of Atabapo from the triple junction (cross-shaped) Santa Cruz with Atacavi and the Guasacavi (Colombia), and Temi, Atabapo true origin, all with dark brown water, flows in the Orinoco twinned with earthy Guaviare waters. Tracing the Atabapo-Temi until Yavita port, then overland to reach Maroa, you can then go down the Guanía-Rio Black to Brazil, which is the shortest way to the southern border.
According to calculations, the tributaries of the watershed between the rivers Guanía Temi and has a level difference is less than 10 mt. by what has been said of the project an artificial canal that waters of these two basins, or narrow gauge train about 15 km. fast giving way to the boats that traffic between Guanía Samariapo and without having to go through the Upper Orinoco and Cassiquiare, saving several days of travel by this route short.
Among the major tributaries is the pipe Caname Atabapo with the detail that this pipe headers ¬ so relatively near the Orinoco, but instead of going to its giant neighbor, its waters flow westward to search the river Atabapo; near the headwaters of the pipe is Caname Ca ¬ rida yes runs to the Orinoco. During the rainy season stronger, they are huge gaps and overflows connecting the headwaters of these two pipes and in this way to navigate with small canoes and a good practical, the Atabapo Orinoco, through what are large savannas summer.
Another tributary, the Sipapo with 270 km. of course, forms a sub. basin of about 13,000 km2. It collects water from the mountains of Sipapo. Born south of this mountainous west direction, straightens its course to the north, running parallel to the Orinoco to its mouth on it, opposite the island of mouse. But before receiving the Cuao of greenish waters pure and capricious course, the Guava and Autana of dark waters, all with beautiful and abundant waterfalls and wonderful natural monuments, this relatively near Puerto Ayacucho. Without cheap energy untapped yet Cataniapo River.
A few kilometers from the state capital leads the torrential Cataniapo the Orinoco River, with the characteristic green color of its waters, which have already been studied by Humboldt makes supplanted purity of drinking water to the capital. During the year 1981, projected the works of the great river hydroelectric Cataniapo, of vital importance to the region and neighboring areas. Just 45 km. Puerto Ayacucho, the dam would have a height of 35 mt. with a reservoir of 655 million mt. Cubic. Can be reached in the winter have a length of 20 kilometers, covering an area of 650 km ². As for the mechanical equipment is designed for 4 turbines with a capacity of 10,000 kW. The pipe borne water would gravity Puerto Ayacucho.