Brief  Description  of the Basin

• The catchment area of the Ganga lies between east longitudes 73° 30’ to 89° 0’ and north latitudes 22° 30’ to 31° 30’ which falls in four countries, namely India, Nepal, Tibet (China), and Bangladesh with major part in India.

• The Ganga basin extends over an area of 1,086,000km².

• The drainage area lying in India is 862,769 km²  which is nearly 26.2% of the total geographical area of the country.

• The total length of the Ganga River is 2,525 km. and the navigable length is 631 km.

• The entire length of Ganga River in India can be divided in three stretches:

  • Upper reach from the origin to Narora;

  • Middle reach from Narora to Ballia, and

  • lower reach from Ballia to its delta.

• The main physical sub-divisions of the Ganga basin are

  • The Northern Mountains, comprise the Himalayan ranges including their foothills

  • The Gangetic Plains between the Himalayas and the Deccan plateau and

  • The Central Highlands. lying to the south of the Great Plains consists of mountains.

• Predominant soil types found in the basin are sand, loam, clay and their combinations, such as sandy loam, loam, silty clay loam and loamy sand soils.

Topography

• The Ganga and its tributaries have formed a large flat and fertile plain in North India.

• The availabilities of abundant water resources, fertile soil, and suitable climate have given rise to a highly developed agriculture based civilization and one of the most densely populated regions of the world.

• The net sown area in the Ganga basin in India is around 44 million hectares (M-ha) and the net irrigated area is 23.41 M-ha.

• Migration of the tributaries draining the eastern part of the basin has resulted in conspicuous back-swamp and meander bolt deposits. These sedimentological features play a dominant role in the hydrodynamics of the region.

Water Potential of the Basin

Surface Water potential

525.02Km³

Ground Water potential

170.99Km³

Hydropower Potential

The hydroelectric potential of the Ganga basin has been assessed 20711 MW. Out of the 142 identified schemes in the basin , schemes with a total installed capacity of 4987 MW are in operation as on 31.7.2014 and schemes with an installed capacity of about 1751 MW are in various stages of construction. (Source: www.cea.nic.in )

Water Utilization

Surface Water Utilization

Drinking and Irrigation purposes

Ground Water Utilization

Drinking and Irrigation purposes

Tributaries with Drainage Area in sq. km.

Name of the Tributary

Drainage area (Km²)

Ganga including Karmnasa Baya, Bagmari-Pagla

113,163

Yamuna including Chambal, Betwa & Ken

363,082

Sone

71,259

Ghaghra

57,647

Ramganga

32,493

Damodar including Khari-Gangur-Ghia

31,220

Gomti

30,435

Rupnarayan including Haldi, Rasulpur & Kangsabati

23,760

Mahananda

17,440

Tons

16,860

Kiul-Harohar

16,661

Kosi

11,070

Burhi-Gandak

10,150

Punpun

8,530

Mayurakshi-Babla

8,530

Gandak

7,620

Ajay

6,050

Jalangi

5,640

Badua-Chandan

4,840

Bagmati

3,720

Adhwara

2,600

Kamla-Balan

2,980

Tidal rivers

15,650

Major Projects

Ganga canal systems (Upper Ganga Canal, Madhya Ganga Canal, Lower Ganga Canal, Agra Canal, East Ganga Canal), Yamuna Canal Systems (Eastern Yamuna Canal, Western Yamuna Canal, Betwa Canal, Dhasan canal, Ken Canal, Ghagar Canal, & Sarda Canal), Tehri dam project, Lakhwar dam, Tapovan Vishnugarh project, Ramganga Multipurpose project, Dhalipur Hydropower project, Rihand dam, Chilla Hydrpower project, Tanakpur Barrage, Kishau Dam, Maneri Bhali Hydropower project, Khara Hydropower project, Khodri Hydropower project, Chobro Hydropower project, Rajghat Dam, Halali Dam,Gandhisagar Dam, Ranapratap Sagar Dam, Jawahar Sagar Dam, Chambal Valley Project, Obra Dam, Bansagar Tons dam, Parbati dam, Matatila Reservoir, Ramsagar Dam, Massanjore Reservoir, Dhauliganga Power Project, DVC System (Tilaiya, Konar,Maithon & Panchet dams), Farakka Barrage

Water Quality of Ganga Basin

A sharp decline in the quality of Ganga water is due to increasing level of pollution from urban and industrial areas. The problem has arisen largely due to the discharge of untreated urban wastes and industrial effluents from the cascade of large and medium cities located along the course of Ganga and its tributaries. Although Ganga is considered as a holy river in mythology, people do not hesitate while dumping domestic and industrial waste in the river.

Numerous cities located in the Ganga basin generate and discharge huge quantities of wastewater, a large portion of which eventually reaches the river through natural drainage system. Over the years, the Ganga and its tributaries have become the channels of transport of industrial effluents and the drains for the wastewater of the cities. It is estimated that some 900 million litres of sewage is dumped into the Ganga every day; three-fourths of the pollution in the Ganga is from untreated municipal sewage. In particular the middle reach of the basin between Kanpur and Buxar is the most urbanized and industrialized, as also the most polluted segment of the basin. Municipal and industrial wastes with dangerous concentration find entry into the watercourse in this segment and pose a grave threat to society.

In the hilly reaches up to Rishikesh, Ganga water is quite clean except for sediments. From Rishikesh onwards, disposal of sewage into Ganga begins. Besides the municipal waste of Rishikesh and Haridwar, industrial units discharge partly treated effluents into the river. Haridwar City has a population of 1.5 lakh and nearly 60,000 people visit the city every day on an average. This number rises to a few lakh on important religious days and may go up to 15 lakh on the auspicious days during Kumbha Mela (fair).

Considerable lengths of sewer lines are clogged by silts that flow in from the adjoining hills. Further downstream from Haridwar, Ganga flows through Bijnor, Garhmukteshwar,Narora and Kannauj. Here, water is not much polluted as these two towns do not have any large industry. Moving downstream, the situation changes for the worse at Kanpur from the quality point of view. Sewage from the city (population 2.7 million) coupled with untreated toxic waste discharge from about 150 industrial units results in severe damage to water quality.

The mean value of DO at 3 mg/l at Jajmau, near Kanpur, reflects the levels of pollution caused by discharge from 80 tanneries and other industries. At Allahabad with population of more than a million, municipal wastes are the major contributor to river pollution. Yamuna whose water is highly polluted joins Ganga at Sangam. Large volume of municipal and industrial waste is dumped in the river at Varanasi, a city with approximately 1.2 million population. The Varuna River, which joins the Ganga in the vicinity of Varanasi, receives waste from many drains. Besides, due to the religious belief that those who die in Varanasi are sure to go to heaven, on average, more than 40,000 dead bodies are cremated on the river bank and the ashes and remains are dumped in the river.

Entering in Bihar, a number of industries (including fertilizer and oil refining) have come up along Ganga River. Patna is the most populous city whose wastes are dumped in the river. At Kolkota in West Bengal, the Hooghly (Ganga) river basin is highly populated as the waster from numerous industries as well as municipal sewage is dumped in the river.

In view of the magnitude of water quality problems in the Ganga basin, two actions plans were launched by the government of India: the Ganga action plan and the Yamuna action plan.

Problems in Ganga Basin

• Highly productive irrigated agriculture is practiced in fertile soils of Ganga basin since time immemorial and recent rapid industrialization has generated large demands for water and hydropower. The domestic water demand in high-population density urban areas scattered throughout the Ganga basin has outstripped the supplies.
• Bangladesh which lies at the downstream end, requires a mechanism that can augment the dry season flow as well as control floods.
• The irrigation infrastructure in Ganga basin, as elsewhere in the country, is getting old. A number of large irrigation projects are over 100 years old. During the past 50 years, many of these have been modernized by replacing the weirs and anicuts by gated barrages and repairing the canal systems. Large dams on the perennial rivers are an inevitable solution to the above problems. A few smaller projects have been already completed and several larger ones are planned in the Himalayan catchments of the northern tributaries to the Ganga and Brahmaputra. There is no doubt that storage of even a fraction of the huge flow and generation of hydroelectricity would go a long way in advancing economic transformation and development within the GBM. In short, these dams have been described as panacea for the poverty in the Himalayan region. However, decisions regarding construction of these dams is no longer guided by hydrology and engineering; other factors have started influencing the decisions.
• The basic problem in utilizing water resources in the Ganga basin is that in relation to the relatively large annual flow in the basin, the storage capacity of existing and foreseeable reservoirs in India is not large enough to permit conservation of flows during high flow season. The live storage capacity of all reservoirs in the Ganga basin is less than one-sixth of the annual flow, which does not permit a significant degree of flow regulation. Lean season flows in the basin without an adequate storage backup are not sufficient to meet the requirements for various demands while monsoon flows are so high that the Ganga and its tributaries remain in spate almost every year.
• Many of the diversion works are not backed by any large upstream storage. Therefore the supply of water for irrigation is limited by the flow of the rivers. Only a few tributaries, namely Chambal, Betwa and Sone have large reservoirs and are relatively better developed.
• Although there is a vast canal networks in Upper Ganga basin, there are no large existing reservoirs except on Ramganga. The construction of Tehri Dam has not only stabilised irrigation facilities in about 6lac hectare area in Ganga Yamuna doab but it has created an additional irrigation of about 2.7lac hectare. Besides 300cusec water is being supplied to Delhi through Upper Ganges Canal after the construction of the Tehri Dam 
• In the Yamuna system, the possibility of any upstream reservoir in near future is bleak. Although the Lakhwar Vyasi Dam is under construction for over 3 decades, no significant progress has been made. Similarly, two other reservoirs, namely Kishau and Renuka are in pipeline for more than 10 years. Gandhisagar dam on Chambal River with a storage capacity provides regulated supplies to Rana Pratap Sagar, Jawahar Sagar and Kota Barrage.
• Rihand dam on a tributary of Sone River is the other large reservoir in the system. Rihand is primarily a hydropower station and is operated to meet the peaking demands. The power releases from the project supplement Sone Barrage particularly during dry season. Bansagar an interstate project of UP, Bihar and Madhya Pradesh is nearing completion. It will further improve the water availability at Sone barrage.
• Sharda Sahayak and Saryu Nahar in U.P. and Kosi and Gandak Projects in Bihar also do not have any back up storage. Despite being very attractive hydropower projects, Karnali and Pancheshwar projects, little headway is made in construction. Kosi and Gandak dam projects are still on drawing boards. There appears to be poor coordination between India and Nepal on joint execution of projects.
• Delay in implementing the projects will result in escalation of costs. Irrigation potential developed from surface water is around 45% and that from ground water is around 80% in Bihar while the same in U.P. is around 60% and 90% respectively.
• After the formation of Jharkhand and Uttaranchal States, the hydropower potential in U.P. and Bihar is only 403 and 60MW respectively. This has been developed to the extent of 70 to 80 percent. The hydropower potential in Uttaranchal is about 9,341MW of which only 9% is developed. Similarly in Jharkhand, only 15.73% of the total 478MW has been developed. This underlines the need for more large dams to be taken up in Uttaranchal for hydropower generation and these will also provide regulated releases to stabilize existing irrigation systems in Ganga and Yamuna basins.
• No large reservoir has been constructed on Ken River which is a major tributary of Yamuna. Ken multipurpose project has been under consideration for several decades but no progress was made in absence of agreement on sharing of its waters between UP and MP. This project will also transfer surplus water to Betwa basin where construction of Rajghat and Matatila have affected the development in the upstream reaches.
• Development of large reservoirs in southern tributaries of Ganga has not been satisfactory. The North Koel dam project remains to be completed for several decades for some environmental hitches. Similarly Auranga dam is yet to be taken up for implementation. Bue even pending projects are completed, after the total live storage capacity created in Ganga basin will be about 52 BCM. This will be less than 10% of the average annual runoff and less than 20% of the utilizable runoff. Therefore, sincere efforts are needed to complete the major storage dams which have already been identified in Uttaranchal, U.P., Bihar and M.P. Of late, the problems encountered in constructing dams in India are increasing.
• A majority of good storage sites of the basin are in Nepal and this is a cause of delay in the construction of dams on the northern tributaries of Ganga. Agreements with Nepal are to be made for implementation of identified projects.
• In the Ganga basin, the flooding problem is mainly confined to the middle and terminal reaches. In general, the severity of the problem increases from west to east and from south to north. The worst flood affected states in the Ganga basin are Uttar Pradesh, Bihar, and West Bengal. In Uttar Pradesh, flooding is largely confined to the eastern districts where the rivers that cause flooding include the Sarada, the Ghagra, the Rapti, and the Gandak. The major causes of flooding here are drainage congestion and bank erosion. North Bihar is in the grip of floods almost every year due to the spillage of rivers. In West Bengal, floods are caused due to the drainage problems as well as tidal effects. The Ganga Flood Control Commission was set up by the Government of India for flood management in the Ganga Basin.
• The Ganga basin has an extremely high density of population. This dense population, coupled with high growth rate is expected to generate huge demand for additional water in Ganga basin. Further, industries are rapidly growing in the region. This will create substantial additional water demand as well as problems of water quality. This scenario will be similar in all the countries in the Ganga basin:
• Nepal, India, and Bangladesh. In the absence of a well-coordinated water resources developing and sharing agreement, the local, regional, and international conflicts may become critical. Nepal and India should come to agreements on joint developments of major water projects. Between Bangladesh and India, the sharing of the flow in the Ganga below Farakka has evaded a long term solution. In the overall interest of sustainable development in the region, early resolution of these problems is very much needed.

Mythology

The Ganga River has been considered as the most sacred river of India in Puranas. It is called as Ganga Maa (or mother Ganga) or Ganga ji (or reverend Ganga). People of India believe that a bath in the holy waters of Ganga washes all the past sins of a person. Numerous pilgrimages such as Allahabad, Rishikesh, Haridwar, Varanasi and Patna are present all along the river. Water from the Ganga is used to cleanse any place or object for ritual purposes. Bathing in the river is believed to wash away one’s all sins. The word Ganga is considered as a synonym of pure and holy water. According to a mythological legend, Lord Brahma collected the sweat of Lord Vishnu’s feet and created Ganga. Being touched by two members of the Trimurti (Brahma, Vishnu, and Mahesh), Ganga became very holy. The other synonyms of Ganga are Vishnu Padee, Mandakini, Devnadi, Sursari, Tripathga, Jahanvi, Bhagirathi, Patalganga, etc.