The Ganga River Basin

The Ganga river and its tributaries drain more than one million sq. km of China, Nepal, India and Bangladesh. The Ganga basin in India, which includes the Yamuna sub-basin, covers over 861,000 sg. km in northern India or one fourth of India's geographical area (Das Gupta 1984:5). The Ganga river begins at the confluence of the Bhagirathi and the Alaknanda, located within the Himalayan foothills of northern India. The Bhagirathi flows from the Gangotri glacier at Gomukh and the latter from a glacier near Alkapuri. Flowing across the great alluvial Indo-Gangetic plains, the Ganga is bordered by the Himalayas to the north and the Vindhya-Satpura ranges to the south.

The mainstem that carries the name Ganga is entirely within India and this channel and its water are what are most sacred to Hindus. Along the river's traverse, large tributaries enter the Ganga and significantly increase its flow and change its character. The Ganga is joined by the Ram Ganga, Yamuna, Ghaghara, Gomti, Gandak and Kosi tributaries. However, the major tributaries, the Ram Ganga, Yamuna and Ghaghara are the only Himalayan rivers that have significant base and flood flows. Water also comes from snowmelt and from monsoon season rainfall. The rivers of the Ganga basin carry one of the largest sediment loads in the world. Today sediment loads in the Ganga are higher than in the past due to the complete deforestation of the Gangetic plains and the ongoing deforestation of the Himalayan foothills.

The river is dewatered at several sites. The most upstream site is located at Haridwar, where the plains meet the foothills of the Himalayas. At Haridwar, a significant portion of the main stream is diverted into the Upper Ganga Canal. This is an irrigation channel that feeds the alluvial tract lying between the Ganga and Yamuna rivers. The long canal system through the Doab has two names. The upstream part is referred to as the Upper Ganga Canal. The downstream section, starting at Aligarh, is the Lower Ganga Canal. At Kanpur, the irrigation return flow reenters the parent stream. Scientists argue that the reach of the river from Kannauj to Allahabad is particularly vulnerable to human induced pollution because significant dewatering has occurred upstream. Beyond this reach, the Ganga gains stream flow from the Yamuna river at Allahabad and from the Ghaghra, Kosi and Gandak rivers farther downstream.

The level of pollution in the river depends upon the concentraion of pollutants and the discharge of the river. Both concentration and discharge are affected by hydrological, geomorphologic, topographic and cultural factors. Today, over 45 million people reside in the Ganga basin. The Ganga passes alongside 29 cities with populations above 100,000, 23 cities with populations between 50,000 and 100,000, and 48 towns less than 50,000. The Central Pollution Control Board estimates that the main sources of pollution along the reach of the river are urban liquid waste (sewage/sullage), industrial liquid waste, large scale bathing of cattle, throwing of dead bodies in the river, surface run-off from solid waste landfills and dumpsites, and surface runoff from industrial solid waste landfills or dumpsites. The Central Pollution Control Board reports that three-fourths of the pollution of the river comes from the discharge of untreated municipal sewage, of which 88% is created in Class-I cities (cities with populations above 100,000). Without more specific data on discharge amounts, however, the Central Pollution Control Board can only provide estimates that are tallied from the estimates of wastewater flows generated in each of the cities through which the Ganga passes. Generally, scientists cite the loss of discharge as the more serious factor contributing to the rise in levels of pollution since without adequate flow, toxins and bacteria cannot be flushed and degraded.

Industrial wastewater is discharged by a number of industries situated in this riparian zone. In 1995, the Central Pollution Control Board listed 191 grossly polluting industries in the state of Uttar Pradesh, 6 in the state of Bihar, and 67 in the state of West Bengal. These industries were discharging toxic substances into effluent flows with BOD concentrations of more than 100 mg per liter and each unit was generating over one million liters of wastewater per day. The industries represented in this river basin are sugar and paper mills, cloth, woolen, cotton and rayon mills, tanneries, ordinance factories, battery industries, thermal power houses, chemical plants, metal and steel factories, distilleries, and fertiliser corporations. Heavy metals such as cadmium, zinc, nickel, lead, chromium and copper are concentrated in the river water and the sediments. The Central Pollution Control Board reports high levels of zinc and nickel in the sediment of the Yamuna river downstream from the capitol city of Delhi.

The Ganga basin is the cradle of Hindu and Buddhist pilgrimage culture. Some of the most important centers of spiritual learning and healing have thrived for centuries along her banks and those of her tributaries. At the headwaters of the Ganga in the Himalayas, sacred shrines at Tapavan, Gomukh, Bhojbasa, and Gangotri mark the sources of her power. The shrines of Kedarnath and Badrinath also celebrate their position in the upper reaches of the watershed. Farther downstream in the Himalayas are Uttarkashi and Rishikesh and along the plains lie Haridwar, Allahabad (Prayag), Banaras, Vindhyachal, Nadia and Kalighat. Along the river Yamuna, we find the sacred complexes of Mathura and Vrindavan and inland within the Ganga basin, the Hindu center of Vindyachal and the Buddhist sites of Gaya, Rajgir and Nalanda. In these pilgrimage centers and in countless other smaller sacred spots along her great traverse, pilgrims worship the Ganga and carry away her pure water for worship and purification.