When compared to the other major rivers in India, the Brahmaputra is less polluted but it has its own problems: petroleum refining units contribute most of the industrial pollution load into the basin along with other medium and small industries. The main problem facing the river basin is that of constant flooding. Floods have been occurring more often in recent years with deforestation, and other human activities being the major causes.
About 1,800 miles (2,900 km) long, the river is an important source for irrigation and transportation. Its upper course was long unknown, and its identity with the Yarlung Tsangpo was only established by exploration in 1884-86. This river is often called Tsangpo-Brahmaputra river. The average depth of river is 124 feet (38 m) and maximum depth is 380 feet (120 m).