About River Ganga Basin and its tributaries
- The Ganga basin outspreads in India, Tibet (China), Nepal and Bangladesh over an area of 10,86,000 Sq.km.
- In India, it covers states of Uttar Pradesh, Madhya Pradesh, Rajasthan, Bihar, West Bengal, Uttarakhand, Jharkhand, Haryana, Chhattisgarh, Himachal Pradesh and Union Territory of Delhi.
- It drains an area of 8,61,452 Sq.km which is nearly 26% of the total geographical area of the country.
- The basin is bounded by the Himalayas on the north, by the Aravalli on the west, by the Vindhyas and Chhotanagpur plateau on the south and by the Brahmaputra Ridge on the east.
- The Ganga rises in the Gangotri glacier in the Himalayas at an elevation of about 7,010 m in the Uttarkashi district of Uttarakhand.
- At its source, the river is called as the Bhagirathi.
- It descends down the valley upto Devprayag where after joining another hill stream Alaknanda, it is called Ganga.
- The total length of river Ganga up to its outfall into Bay of Bengal is 2,525 km.
- The principal tributaries joining the river from right are the Yamuna and the Son.
- The Ramganga, the Ghaghra, the Gandak, the Kosi and the Mahananda join the river from left.
- The Chambal and the Betwa are the two other important sub- tributaries.
Significance of River Ganga basin
- The major part of basin in Indian Territory is covered with agricultural land accounting to 65.57% of the total area and 3.47% of the basin is covered by water bodies.
- The basin provides over a third of India’s available surface water and contributes more than half the national water use, of which 90% is for irrigation.
- The Ganga river basin is the most populated river basin in the world and is home to half the population of India, including two-thirds of the nation’s poor people.
- The government has committed to reduce pollution in the Ganga by 70% by March 2019.
- The World Bank has submitted a report on the assessment on the future of the Ganga river basin to the Central Water Commission.
- The aim of the report was to Strengthen the “capacity for strategic basin planning, develop a set of scenarios for the development of the Ganga basin and build a strong and accessible knowledge base.”
- The assessment report is based on river flow, water quality and groundwater levels in the different States and regions within the Ganga river basin.
- Also, it has taken into account the land use, infrastructure, population, industry and agriculture settings as well as the precipitation and temperature settings.
- The report has triggered a new protest by Ecologists and river activists to highlight the government’s apathy towards addressing ill-healthof Ganga.
Highlights of the World Bank assessment
- As flow in the river would decline and pollution will worsen, there will be less irrigation and drinking water available in the areas of the Ganga Basin. As a result-
- There could be three-fold rise in crop failures in the Ganga river basin.
- Drinking water shortage may go up by as much as 39% in some States between now and 2040.
- If there is no intervention done-
- Uttarakhand, Himachal Pradesh, Uttar Pradesh and Bihar are likely to see a deficit in irrigation water of 28%, 10%, 10% and 15% respectively in 2040 as compared to the current levels.
- Madhya Pradesh would see a 39%, Delhi 22% and Uttar Pradesh a 25% deficit in drinking water during the same period.
- The groundwater is expected to be extracted more than double, which would lead to an increase in the critical blocks.
- River water flow in the river is predicted to decline compared to present levels.
- The critical water quality and environmental flow conditions will deteriorate further.
- There is no single solution to this problem and combinations of different interventions are required as discussed below.
- Increasing water use efficiency and implementing a ‘more job per drop’ rather than striving for wholesale crop production.
- Improvement of municipal waste water treatment to reduce pollution loads, which would result in availability of clean water as well as a drastic reduction in water-related illnesses and deaths.
- Some environmentalists suggest that the natural flow of the river should be maintained as it has propensity to clean itself.
Section : Environment & Ecology