TIET RIVER

Portuguese Rio Tiet, So Paulo estado (state), southeastern Brazil, rising in the Serra do Mar, just east of So Paulo city, and flowing in a northwesterly direction for about 700 miles (1,130 km) before joining the Paran River at Ilha Grande, just above Urubupung Falls. Its major tributaries include the Piracicaba, Jacar, and Sorocaba, and it drains an area of 27,410 square miles (70,990 square km). Several of the state's large cities are located on or near the Tiet, but navigation along its course is impeded by frequent falls and rapids. The latter have been harnessed for power in several places.