The river Ganga occupies a unique position in the cultural ethos of India. Legend says that the river has descend. from Heaven on earth as a result of the long and arduous prayers of King Bhagirathi for the salvation of his d.eas. ancestors. From times immemorial. the Ganga has been India, river of faith, devotion and worship. Millions of Hindus accept its water as sacred. Even today, people carry treasured Ganga water all over India and abroad because it is "holy.' water and known for its "curative" properties.
However, the river is not just a legend. it is a. a life-support system for the people of India. It is important because:
The densely populatated Ganga basin is inhabited by 37 percent of India's population .
• The entire Ganga basin system effectively drains eight states of India.
• About 47 per cent of the total irrigated area in India is located in the Ganga basin alone.
• It has been a major source of navigation and communication since ancient times.
• The Indo-Gangetic plain has witnessed the blossoming of India, great creative talent.
The Ganga rises on the southern slopes of the Himalayan ranges (Figure 2) from the Gangotri glacier at 4000 m above mean sea level. It flows swiftly for 250 km in the mountains, descending steeply to an elevation of 288 m above mean sea level. In the Himalayan region the Bhagirathi is joined by the tributaries Alaknanda and Mandakini to form the Ganga. After entering the plains at Hardiwar, it winds its way to the Bay of Bengal, covering 2,500 km through the provinces of Uttar Pradesh. Bihar and West Bengal (Figure 1). In the plains it is joined by Ramganga, Yamuna, Sai, Gomti, Ghaghara, Sone, Gandak, Kosi and Damodar along with many other smaller rivers.
The Ganga river carries the highest silt load of any river in the world and the deposition of this material in the delta region results in the largest river delta in the world (400 km from north to south and 320 km from east to west). The rich mangrove forests of the Gangetic delta contain very rare and valuable species of plants and animals and are un parallel among many forest ecosystems.