| Sarabia, Jaltepec|
| El Corte, Uxpanapa|
Sierra de Niltepec
| 1,163 m/s (41,071 cu ft/s)|
Antonio Dovalí Jaime Bridge
The Coatzacoalcos is a large river that feeds mainly the south part of the state of Veracruz; it originates in the Sierra de Niltepec and crosses the state of Oaxaca in the region of the Isthmus of Tehuantepec, flowing for 325 kilometres (202 mi) toward the Gulf of Mexico. Tributaries include El Corte, Sarabia, Jaltepec, Chalchijalpa, El Chiquito, Uxpanapa, and Calzadas. The merging of all these rivers creates one of the largest current flows in the entire region. Two-thirds of the streams are navigable.
Juan de Grijalva's 1518 expedition discovered the river. Hernan Cortes sent Diego de Ordaz to explore the river as a possible port.
Coatzacoalcos River Wikipedia
According to legend, the Olmec god Quetzalcoatl was aboard a raft made of a serpent skin and navigated until getting lost into the horizon. Ever since, the river has been known as Coatzacoalcos, which means “the place where the serpent hides” in Nahuatl.
The city of Coatzacoalcos, at the river's mouth, is one of the most commercial and industrialized ports, considered the third most important in the Gulf of Mexico, offering one of the most important means of transportation for an international commerce whose products are important to the local industrial farming business, forestry, and commerce in general for the Isthmus of Tehuantepec.
The Coatzacoalcos is also among the world's most contaminated rivers, partly because of the lack of environmental laws protecting the public water. According to the Mexican Center of Environmental Law (CEMDA) the biggest polluting body is the petrochemical industry of Mexico Pemex.