The Papaloapan River () is one of the main

river 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 wate ...

s of the

Mexican state The states of Mexico are first-level administrative territorial entities of the country of Mexico, which is officially named Mexico, United Mexican States. There are 32 federal entities in Mexico (31 states and the capital, Mexico City, as a sepa ...

Veracruz Veracruz (), formally Veracruz de Ignacio de la Llave (), officially the Free and Sovereign State of Veracruz de Ignacio de la Llave ( es, Estado Libre y Soberano de Veracruz de Ignacio de la Llave), is one of the 31 states which, along with Me ...

. Its name comes from the

Nahuatl Nahuatl (; ), Aztec, or Mexicano is a language or, by some definitions, a group of languages of the Uto-Aztecan language family. Varieties of Nahuatl are spoken by about Nahua peoples, most of whom live mainly in Central Mexico and have smaller ...

''papaloapan'' meaning "river of the

butterflies Butterflies are insects in the macrolepidopteran clade Rhopalocera from the Order (biology), order Lepidoptera, which also includes moths. Adult butterflies have large, often brightly coloured wings, and conspicuous, fluttering flight. The ...

". In 1517, Juan de Grijalva's expedition spotted the river, naming it Río de Alvarado.Diaz, B., 1963, The Conquest of New Spain, London: Penguin Books, The Papaloapan rises in the Sierra Madre de Oaxaca on the border between the states of

and

Oaxaca Oaxaca ( , also , , from nci, Huāxyacac ), officially the Free and Sovereign State of Oaxaca ( es, Estado Libre y Soberano de Oaxaca), is one of the 32 states that compose the political divisions of Mexico, Federative Entities of Mexico. It is ...

. It is formed where the

Santo Domingo River Santo Domingo River is a river of Venezuela. It is part of the Orinoco River basin. See also *List of rivers of Venezuela This is a list of rivers in Venezuela. By drainage basin This list is arranged by drainage basin, with respective tributa ...

and the

Valle Nacional River The Valle Nacional River is a river of Oaxaca state in Mexico. The river originates in the Sierra Juárez. The ecology of the region, originally one of pine forests, is threatened by logging, agriculture and grazing. The Valle Nacional flows past ...

join to the southwest of San Juan Bautista Tuxtepec in

. The

Tonto River The Tonto River is a river of Oaxaca, Mexico that flows from the mountains of Zongolica. It is dammed by the Miguel Alemán Dam near the town of Temascal or Nuevo Soyaltepec, forming the Miguel Alemán Lake. Below the dam, the river flows southea ...

is another major tributary. The Papaloapan meanders for in a northeasterly direction through the coastal plain before draining into

Alvarado Lagoon The Alvarado Lagoon System is a large estuary and wetland complex in Veracruz state of eastern Mexico. It is located on the southern Gulf Coastal Plain, where the Papaloapan and Blanco rivers meet the Gulf of Mexico. Geography The lagoon system ...

. The river basin covers , the second largest in Mexico, and contains 244 municipalities with a population of about 3.3 million people. The cities of San Juan Bautista Tuxtepec and Tlacotalpan (Veracruz) are situated on the banks of the Papaloapan. In the past the Papaloapan river basin was subject to frequent flooding, with the damage sometimes compounded by cyclones. A particularly severe flood in September 1944 covered , with great loss of life and property. The

Miguel Alemán Dam The Miguel Alemán Dam is on the Tonto River in the Papaloapan Region of Oaxaca state in southern Mexico, just upstream from the town of Temascal or Nuevo Soyaltepec, forming the Miguel Alemán Lake with an area of 47,800 hectares. The dam opera ...

on the Tonto river reduced the problem, but further floods occurred after it had been completed in 1955. A flood in 1958 covered and one in 1969 covered . Meanwhile, the drainage capacity of the Papaloapan river was being reduced by silt carried by the Santo Domingo river. Construction of the

Cerro de Oro Dam The Cerro de Oro Dam ( en, Gold Hill Dam), also called the Miguel de la Madrid Hurtado Dam, is on the Santo Domingo River in the San Juan Bautista Tuxtepec municipality of the Papaloapan Region of Oaxaca state in southern Mexico. The dam operates ...

in 1989 on the Santo Domingo river reduced the extent of floods to a manageable level. The states of Oaxaca and Veracruz are cooperating in developing the river basin. Plans include irrigation to improve agricultural production, promotion of forestry and fish farming and improvements to roads and river navigation. The planned projects will be designed to avoid ecological damage. Environmental damage has been the subject of considerable study.Patrick H. Cosby, "Leviathan in the Tropics: A postcolonial environmental history of the Papaloapan Projects in Mexico." PhD diss. University of Florida 2011.

References

Geography of Mesoamerica Rivers of Veracruz Petén–Veracruz moist forests {{Mexico-river-stub