The Tietê River is a Brazilian river in the state of São Paulo. The name Tietê was registered for the first time on a map published in 1748 by d’Anville. The name signifies "The truthful river", or "truthful waters” in Tupi.
Navigation on the waterway Tietê-Paraná
In several dams, for instance, the Barra Bonita, systems of locks were implemented to make navigation on the river possible. Many barges transport produce of the region at a cost which is lower than road transport. The waterway of the Tietê-Paraná permits navigation over a length of between Conchas on the River Tietê and São Simão, on the Paranaíba Riverand then, up to ltaipu, attaining of waterway. It already moves more than one million metric tons of grains per year, at an average distance of. If we calculate the loads with a small distance like sand, gravel, and sugarcane, the movement on the River Tietê is approximately 2 million metric tons.'' Of this waterway, about of the Tietê River is fully navigable
Although the Tiete River is said to be one of the most important rivers economically for the state of São Paulo and for the country, the Tietê River is best known for its environmental problems, especially for the stretch through the city of São Paulo. The pollution of the Tietê River did not start long ago. Even in the 1960s, the river still had fish in the stretch within the capital. However, the environmental degradation of the Tietê River started subtly in the 1920s with the construction of the Guarapiranga Reservoir, by the Canadian firm São Paulo Tramway, Light and Power Company, for the later generation of electrical energy in the hydroelectric power stations Edgar de Souza and Rasgão, situated in Santana de Parnaíba. This intervention altered the regime of the waters in the capital and was accompanied with some rectification works also by the São Paulo Tramway, Light and Power Company, which left the bed of the river less winding, in the region between Vila Maria and “Freguesia do Ó.” Even in the 1920s and 1930s, the river was utilised for fishing and sports activities were famous as were the nautical races on the river. During this period boat race clubs were created along the length of the river, such as the Club of the Tietê races and the Espéria, clubs that exist till now. , with the Tietê River, in São Paulo. In September 2010 National Geographic identified the river as the most polluted in Brazil. Several species from the Tietê River are considered threatened and one of these, the catfish Heptapterus multiradiatus, is possibly already extinct.
The Tietê project
The governor of São Paulo ordered Sabesp, the company responsible for sanitation in the state, to establish a program to clean up the river. The state at the same time sought help at the Inter American Development Bank, and proposed a project based on the former studies of SANEGRAN. , west of the Metropolitan Region of São Paulo. After more than 16 years, the cleaning up of the River Tietê is still far short of desired levels, but encouraging progress has been made. At the end of the 1990s, the capacity of sewage treatment has been expanded: Sabesp has expanded the treatment capacity of the Wastewater Treatment Plant in Barueri, and the Seasons of the Sewage Treatment at San Miguel, to treat the rest of the sewage of the city of São Paulo.
