, name_etymology = , image = Maranon.jpg , image_size = 270 , image_caption = Valley of the Marañón between Chachapoyas (

Leimebamba Leimebamba (or Leymebamba) is a district of the province of Chachapoyas, located in the northern Peruvian department of Amazonas, in the valley of the Utcubamba River, about 60 kilometers (37 miles) south of Chachapoyas. Geography Leimebamba i ...

) and

Celendín Celendín is an Andean town in northern Peru, capital of the province of Celendín, in the department of Cajamarca. It is on the road between the city of Cajamarca and the city of Chachapoyas. History The history of the city of Celendín beg ...

, map = Maranonrivermap.png , map_size = 270 , map_caption = Map of the Amazon Basin with the Marañón River highlighted , pushpin_map = , pushpin_map_size = 270 , pushpin_map_caption= , subdivision_type1 = Country , subdivision_name1 =

Peru , image_flag = Flag of Peru.svg , image_coat = Escudo nacional del Perú.svg , other_symbol = Great Seal of the State , other_symbol_type = Seal (emblem), National seal , national_motto = "Fi ...

, subdivision_type2 = , subdivision_name2 = , subdivision_type3 = , subdivision_name3 = , subdivision_type4 = , subdivision_name4 = , subdivision_type5 = , subdivision_name5 = , length = , width_min = , width_avg = , width_max = , depth_min = , depth_avg = , depth_max = , discharge1_location= , discharge1_min = , discharge1_avg = , discharge1_max = , source1 =

Andes The Andes, Andes Mountains or Andean Mountains (; ) are the longest continental mountain range in the world, forming a continuous highland along the western edge of South America. The range is long, wide (widest between 18°S – 20°S ...

, source1_location = , source1_coordinates= , source1_elevation = , mouth = Amazon River , mouth_location = , mouth_coordinates = , mouth_elevation = , progression = , river_system = , basin_size = , tributaries_right = Yanayacu, Huallaga, Cahuapanas, Potro, Apaga, Saramiriza, Nieva, Cananya, Chiriaco, Congón, Rumirumi, Shuve, Chumuch, Pusac, Lavasen, Gansul, San Miguel, Challas River, Tantamayo,

San Juan San Juan, Spanish for Saint John, may refer to: Places Argentina * San Juan Province, Argentina * San Juan, Argentina, the capital of that province * San Juan, Salta, a village in Iruya, Salta Province * San Juan (Buenos Aires Underground), ...

, tributaries_left = Tigre, Cunincu, Urituyacu, Nucuray, Ungumayo, Pastaza, Sasipahua, Morona, Cangaza,

Santiago Santiago (, ; ), also known as Santiago de Chile, is the capital and largest city of Chile as well as one of the largest cities in the Americas. It is the center of Chile's most densely populated region, the Santiago Metropolitan Region, who ...

, Cenepa, Chinchepe, Choros, Linlín, Artesamayo, Choropampa, Madgalena, Cortegana, Chipche, Mireles, Chusgón, San Sebastián, Casga, Mamara,

Mayas The Maya peoples () are an ethnolinguistic group of indigenous peoples of Mesoamerica. The ancient Maya civilization was formed by members of this group, and today's Maya are generally descended from people who lived within that historical re ...

, Actuy, Rupac, Yanamayo, Puchca, Contan, Vizcarra , custom_label = , custom_data = , extra = The Marañón River ( es, Río Marañón, ) is the principal or mainstem source of the Amazon River, arising about 160 km to the northeast of

Lima Lima ( ; ), originally founded as Ciudad de Los Reyes (City of The Kings) is the capital and the largest city of Peru. It is located in the valleys of the Chillón, Rímac and Lurín Rivers, in the desert zone of the central coastal part of t ...

, and flowing through a deeply eroded Andean valley in a northwesterly direction, along the eastern base of the Cordillera of the

, as far as 5° 36′ southern latitude; from where it makes a great bend to the northeast, and cuts through the jungle Andes, until at the Pongo de Manseriche it flows into the flat

Amazon basin The Amazon basin is the part of South America drained by the Amazon River and its tributaries. The Amazon drainage basin covers an area of about , or about 35.5 percent of the South American continent. It is located in the countries of Boli ...

. Although historically, the term "Marañon River" often was applied to the river all the way to the

Atlantic Ocean The Atlantic Ocean is the second-largest of the world's five oceans, with an area of about . It covers approximately 20% of Earth#Surface, Earth's surface and about 29% of its water surface area. It is known to separate the "Old World" of Afr ...

, nowadays the Marañon River is generally thought to end at the confluence with the

Ucayali River The Ucayali River ( es, Río Ucayali, ) is the main headstream of the Amazon River. It rises about north of Lake Titicaca, in the Arequipa region of Peru and becomes the Amazon at the confluence of the Marañón close to Nauta city. The city of ...

, after which most cartographers label the ensuing waterway the Amazon River.

Geography

The Marañón River is Peru’s second-longest river, according to a 2005 statistical publication by the

Instituto Nacional de Estadística e Informática The Instituto Nacional de Estadística e Informática (INEI) ("National Institute of Statistics and Informatics") is a semi-autonomous Peruvian government agency which coordinates, compiles, and evaluates statistical information for the country ...

Source of the Amazon

The Marañon River was considered the source of the Amazon River starting with the 1707 map published by Padre Samuel Fritz, who indicated the great river “has its source on the southern shore of a lake that is called Lauriocha, near Huánuco." Fritz believed that the Marañón contributed the most water of all the Amazon's tributaries, making it the most important headstream. For most of the 18th–19th centuries and into the 20th century, the Marañon River was generally considered the source of the Amazon. Later explorations have proposed two headwaters rivers of the Marañon in the high

as sources of the Amazon: the Lauricocha and Nupe Rivers. The Lauricocha and Nupe unite near the village of Rondos to form from their confluence downstream the river that is called the Marañon. Although the Apurimac and Mantaro rivers also have claims to being the source of the Amazon, the Marañon River continues to claim the title of the "mainstem source" or "hydrological source" of the Amazon due to its contribution of the highest annual discharge rates.

Description

The initial section of the Marañon contains a plethora of ''pongos'', which are gorges in the jungle areas often with difficult rapids. The Pongo de Manseriche is the final'' pongo'' on the Marañon located just before the river enters the flat Amazon basin. It is long and located between the confluence with the Rio Santiago and the village of Borja. According to Captain Carbajal, who attempted ascent through the Pongo de Manseriche in the little steamer ''Napo'', in 1868, it is a vast rent in the Andes about 600 m (2000 ft) deep, narrowing in places to a width of only 30 m (100 ft), the precipices "seeming to close in at the top." Through this canyon, the Marañón leaps along, at times, at the rate of 20 km/h (12 mi/h). The ''pongo'' is known for wrecking many ships and many drownings. Downstream of the Pongo de Manseriche, the river often has islands, and usually nothing is visible from its low banks, but an immense

forest A forest is an area of land dominated by trees. Hundreds of definitions of forest are used throughout the world, incorporating factors such as tree density, tree height, land use, legal standing, and ecological function. The United Nations' ...

-covered plain known as the ''selva baja'' (low jungle) or

vian Amazonia. It is home to

indigenous peoples Indigenous peoples are culturally distinct ethnic groups whose members are directly descended from the earliest known inhabitants of a particular geographic region and, to some extent, maintain the language and culture of those original people ...

such as the

Urarina The Urarina are an indigenous people of the Peruvian Amazon Basin ( Loreto) who inhabit the valleys of the Chambira, Urituyacu, and Corrientes Rivers. According to both archaeological and historical sources, they have resided in the Chambira B ...

of the Chambira Basinbr>
the Candoshi, and the Cocama-Cocamilla peoples. A 552-km (343-mi) section of the Marañon River between Puente Copuma (Puchka confluence) and Corral Quemado is a class IV raftable river that is similar in many ways to the Grand Canyon of the United States, and has been labeled the "Grand Canyon of the Amazon". Most of this section of the river is in a canyon that is up to 3000 m deep on both sides – over twice the depth of the Colorado's Grand Canyon. It is in dry, desert-like terrain, much of which receives only 250–350 mm/rain per year (10–14 in/yr) with parts such as from Balsas to Jaén known as the hottest ''infierno'' area of Peru. The Marañon Grand Canyon section flows by the village of Calemar, where Peruvian writer Ciro Alegría based one of his most important novels, ''La serpiente de oro'' (1935).

Historical journeys

La Condamine, 1743

One of the first popular descents of the Marañon River occurred in 1743, when Frenchman Charles Marie de La Condamine journeyed from the Chinchipe confluence all the way to the Atlantic Ocean. La Condamine did not descend the initial section of the Marañon by boat due to the ''pongos''. From where he began his boating descent at the Chiriaco confluence, La Condamine still had to confront several ''pongos'', including the Pongo de Huaracayo (or Guaracayo) and the Pongo de Manseriche.

The Grand Canyon of the Amazon

The upper Marañon River has seen a number of descents. An attempt to paddle the river was made by Herbert Rittlinger in 1936. Sebastian Snow was an adventurer who journeyed down most of the river by trekking to Chiriaco River starting at the source near

Lake Niñacocha Lake Niñacocha (possibly from Quechua language, Quechua ''nina'' fire ''qucha'' lake) is a lake in Peru located in the Huánuco Region, Lauricocha Province, Queropalca District.escale.minedu.gob.pe - UGEL map of the Lauricocha Province (Huánuco ...

. In 1976 and/or 1977, Laszlo Berty descended the section from Chagual to the jungle in raft. In 1977, a group composed of Tom Fisher, Steve Gaskill, Ellen Toll, and John Wasson spent over a month descending the river from Rondos to Nazareth with kayaks and a raft. In 2004, Tim Biggs and companions kayaked the entire river from the Nupe River to Iquitos. In 2012, Rocky Contos descended the entire river with various companions along the way.

Hydroelectric dams

The Marañon River may supply 20 hydroelectric megadams planned in the Andes, and most of the power is thought to be destined for export to Brazil, Chile, or Ecuador. Dam survey crews have drafted construction blueprints, and the environmental impact statements have been available since November 2009 for the Veracruz dam, and since November 2011, the Chadin2 dam. A 2011 law stated "national demand" for the hydroelectric energy, while in 2013, Peruvian President Ollanta Humala explicitly made a connection with mining; the energy is to supply mines in the Cajamarca Region, La Libertad,

Ancash Region Ancash ( qu, Anqash; es, Áncash ) is a department and region in northern Peru. It is bordered by the departments of La Libertad on the north, Huánuco and Pasco on the east, Lima on the south, and the Pacific Ocean on the west. Its capital ...

, and

Piura Region Piura () is a coastal department and region in northwestern Peru. The region's capital is Piura and its largest port cities, Paita and Talara, are also among the most important in Peru. The area is known for its tropical and dry beaches. It ...

. Construction of the 406 MW dam in Chaglla District started in 2012.

Concerns

Opposition arose because the dams are expected to disrupt the major source of the Amazon, alter normal silt deposition into the lower river, damage habitat and migration patterns for fish and other aquatic life, displace thousands of residents along the river, and damage a national treasure "at least as nice as the Grand Canyon in the USA". Residents have launched efforts to halt the dams along the river with conservation groups such as SierraRios and International Rivers. Potential ecological impacts of 151 new dams greater than 2 MW on five of the six major Andean tributaries of the Amazon over the next 20 years are estimated to be high, including the first major break in connectivity between Andean headwaters and lowland Amazon and deforestation due to infrastructure.

References

{{DEFAULTSORT:Maranon River Rivers of Peru Tributaries of the Amazon River

Rivers A river is a natural flowing watercourse, usually freshwater, flowing towards an ocean, sea, lake or another river. In some cases, a river flows into the ground and becomes dry at the end of its course without reaching another body of wat ...

Upper Amazon