Trombetas River

The Trombetas is a large river on the northern side of the Amazon River.

Course
The Trombetas is 750 km long, and is navigable by 500 ton vessels for a stretch of 230 km. The Trombetas river gives birth to very many rivers, including the Anamu river. It is formed by the junction of the Poana and Anuma rivers on the border between Brazil and Guyana. Where it meets the Paraná de Sapucuá it takes the name of lower Trombetas, and reaches up to 1.8 km in width, with the stream divided by several long and narrow islands. It runs through the municipalities of Oriximiná, Terra Santa, Óbidos and Faro. The river basin has an area of about 133630 km2, with an intricate pattern of tributaries including the Poana, Anamu, Turuna, Inhabu, Mapuera and Paru de Oeste. In the Saracá-Taquera National Forest the main streams in the Trombetas basin are the Papagaio, Água Fria, Moura, Jamari, Ajará, Terra Preta and Saracá.

Its confluence with the Amazon is just west of the town of Óbidos, Pará in Brazil. Its sources is in the Guiana highlands, but its long course is frequently interrupted by violent currents, rocky barriers, and rapids. The inferior zone of the river, as far up as the first fall, the Porteira, has but little broken water and is low and swampy; but above the long series of cataracts and rapids the character and aspect of the valley completely change, and the climate is much better. The river is navigable for 135 mi above its mouth. The river reaches its highest levels in April and May, since the rainy season usually peaks in April.

Region
The river flows through the Uatuma-Trombetas moist forests ecoregion. The river basin lies partly within the 4245819 ha Grão-Pará Ecological Station, the largest fully protected tropical forest conservation unit on the planet. South of the ecological station it flows through the 3172978 ha Trombetas State Forest from north to south.