Rio Balsas

Balsas River
Balsas River
Watersheds of Mexico
Native name	Mezcala River
Country	Mexico
Basin features
River mouth	Mangrove Point, Pacific Ocean
River system	Confluence of the San Martín River and Zahuapan River
Physical characteristics
Length	771 kilometers (479 mi)

The Balsas River (Spanish Río Balsas, also locally known as the Mezcala River, or Atoyac River) is a major river of south-central Mexico.

The basin flows through the states of Puebla, Morelos, Guerrero, and Mexico. The river flows through the Sierra Madre del Sur, and empties into the Pacific Ocean at Mangrove Point, adjacent to the city of Lázaro Cárdenas, Michoacán. Several rapids along the course of the Balsas River limit its navigability and thus the river has been largely used for generation of hydroelectric power, flood control and irrigation.

The Balsas River valley was possibly one of the earliest maize growing sites in Mexico, dating from around 9200 years ago. Though it is known that successive communities of Yop, Coixica, Matlatzinca (Chontal), Tlahuica and Xochimilca with Nahua succeeding in the end have lived in the region, archeological excavations in the area are yet to establish the hierarchical succession of the various communities. During the period of 1100–480 BC, the region between the lower Balsas river valley and the Lerma-Santiago River fell under control of the Purépecha Empire.

According to the 1980 Census, 47,000 people lived along the Balsas river banks, spread over 37 communities, within the six municipalities of the region. Nahua peoples constite 47% of the population, 15% are indigenous people (speaking four different languages), other large communities are Mixtec (23%) and Tlapenc (19%), and the balance 4% are Amuzgo. The population increased to 60,000 in the 1990s. The communities, while retaining their individualities, show close linguistic, kinship, and cultural relationships - revealed, for example, when they perform the rituals of patronal feasts.

The upper Balsas River basin includes the State of Puebla, the States of Mexico, Morelos, and the Guerrero Mountain Zone, as well as several river systems of the Mesa Central plateau. The main system is of the Tlapanec River, with tributaries originating in the mountains such as the Oaxaca Mixteca. It is joined by the Amacuzac River fed by streams around Xonacantapec volcano and by the San Jeronimo and Chontalcoatlan rivers. The last two rivers originate around Popocatepetl volcano and flow through the State of Morelos.