Укаяли
The Ucayali River, originating in the Peruvian Andes, borders the eastern part of the El Sira mountain range, with a south - north route. It is characterized by being meandering with few lentic environments in the area adjacent to the aforementioned Cordillera. Its water course has a great lateral migratory activity, which causes the formation of lentic environments - locally known as "tipishcas". These environments are the product of a meander that has been abandoned by the course of the river. The flow of the Ucayali river at the height of Pucallpa is 11,599 m3/s, and at the height of Atalaya 6613 m3/s.