Water Resources Notes in English Class 12 Geography Chapter-4 Book-India-People And Economy

 

Chapter- 4

Water Resources

Water Resources

• Water is a natural resource .

• Life is not possible without water .

• 71% of the earth's surface is covered with water .

• Thus there is abundant water on earth .  

• But fresh (  fresh water)  water is only about 3 percent of the total water.

• The availability of fresh water varies according to place and time. 

• Tensions and conflicts over the distribution and control of water resources have become a subject of dispute between communities, regions and states. 

• Water assessment, proper use and conservation have become essential to ensure development. 

surface water resources

There are four main sources of surface water- 

1. Rivers 

2. Lakes

3. Talaiya 

4. The Pond

Status of water resources 

• There are a total of 10,360 rivers  in the country, including the main rivers and their tributaries   .

• The average annual flow across all river basins in India has been estimated to be 1,869 cubic km.

• However, due to topographical, hydrological and other constraints, only about 690 cubic km (32%) of the surface water available can be used.

• India experiences great spatial variation in rainfall and rainfall is mainly concentrated in the monsoon season. 

• Some rivers in India, such as Ganga, Brahmaputra and Indus, have very large catchment areas. 

• The catchment areas of the Ganga, Brahmaputra and Barak rivers receive relatively higher rainfall. 

• These rivers are found in about one-third of the total area of ​​the country, in which 60 percent of the total surface water resources are found.  

• In southern Indian rivers such as the Godavari, Krishna and Kaveri, most of the annual water flow is utilised but this is still not possible in the Brahmaputra and Ganga basins.

ground water resources

• The water that is inside the earth is called ground water 

1. Low use of ground water Chhattisgarh, Odisha, Kerala

2. Moderate use of groundwater Gujarat, Uttar Pradesh, Bihar, Tripura, Maharashtra

3. Excessive use of ground water Punjab, Haryana, Rajasthan, Tamil Nadu

• If the trend of falling ground water level continues, there will be a need to supply water demand. Such a situation will be detrimental to development and may cause social upheaval and disintegration.

Lagoons and backwaters

• India has a vast coastline and in some states the coastline is highly indented. 

• Due to this reason many lagoons and lakes have been formed. 

• These lagoons and lakes in Kerala, Orissa and West Bengal have large surface water resources. 

• These reservoirs contain saline water, which is used for fish farming and irrigation of certain varieties of rice, coconut etc. 

Water demand and use 

• India is an agricultural economy and about two-thirds of its population depends on agriculture.

• Therefore, in the Five Year Plans, development of irrigation has been given a very high priority to increase agricultural production and multipurpose river valley projects have been developed.

• As -

Bhakra Nangal, Hirakud, Damodar Valley Nagarjuna Sagar,  Indira Gandhi Canal Project etc. have been started. 

• India's current demand for water is high for irrigation needs. 

• Surface and ground water are most used in agriculture. 

• In this, 89 percent of surface water and 92 percent of ground water is used. 

• Whereas in the industrial sector, only 2 percent of surface water and 5 percent of ground water is used.

demand for water for irrigation

• In agriculture, water is mainly used  for irrigation. 

• Most parts of the country are rainless and drought-stricken. 

• North-western India and the Deccan plateau come under this. 

• Farming without irrigation is difficult during the dry season. 

• Even in areas with adequate rainfall like West Bengal and Bihar, scanty rainfall or its failure during the monsoon season creates drought-like conditions which are detrimental to agriculture. 

• Water scarcity makes irrigation necessary  for some crops  . For example, rice, sugarcane, jute etc.  require a lot of water  which is possible only through irrigation.

• Irrigation system makes multiple cropping possible.  It has been found that the agricultural productivity of irrigated land is higher than that of non-irrigated land.

• Punjab, Haryana and Western Uttar Pradesh have  benefited the most from the Green Revolution strategy of agricultural development in the country  .

depletion of ground water 

• In these states, wheat and rice are mainly grown with the help of irrigation.

• These states use a large portion of their potential groundwater, which is causing depletion of groundwater in these states

• In these states , ground water level has gone down  due to excessive use of ground water resources  .

• Fluoride concentration in groundwater has increased due to excessive water extraction in some states, such as Rajasthan and Maharashtra 

• And this led to increased concentration of arsenic in some parts of West Bengal and Bihar.

States suffering from ground water shortage 

•  Fluoride concentration in groundwater has increased due to excessive water extraction in Rajasthan and Maharashtra 

• The concentration of arsenic increased in some parts of West Bengal and Bihar.

Prime Minister Agricultural Irrigation Scheme (PMKSY)

• The main objective of this scheme launched by the Central Government during 2015-16 was  to provide irrigation facilities  for agricultural purposes  . 

• Expansion of cultivable land under irrigation 

• Best use of water through technologies and practices

• Improving water use efficiency on farm, irrigation and other water saving technologies (more crop per drop)

• Achieving development through water conservation such as  regeneration of groundwater, preventing runoff

Possible water problem 

• Due to increasing population, the availability of water  is decreasing day by day. 

• The available water resources are becoming polluted by  industrial, agricultural and  domestic discharges

• Due to this, the availability of useful water resources  is becoming more limited. 

Degradation of water properties

• Water quality refers to the purity of water or water free from unnecessary foreign substances. 

• Water gets polluted by external substances such as microorganisms, chemicals, industrial and other waste materials. 

• These types of substances degrade the properties of water and make it unfit for human use. 

• When toxic substances enter lakes, streams, rivers, oceans and other bodies of water, they dissolve in the water 

• This increases water pollution and aquatic systems are affected due to deterioration in water quality.

• Sometimes the pollutants reach down  and pollute groundwater. 

• The country has two highly polluted rivers, Ganga and Yamuna. 

Water conservation and management

• At present, fresh water is depleting  but the demand for water is increasing,  in such a situation, the need for conservation and management of this important life-giving resource  has increased  for sustainable development  .

• India needs to take immediate steps for water conservation  and make effective policies and laws,  and adopt effective measures for water conservation. 

• Apart from developing water saving techniques and methods,  efforts should also be made to prevent pollution. 

• For watershed development, rain water harvesting, recycling  and reuse of water and long term water supply 

• There is a need to encourage conjunctive use of water.

Prevention of water pollution

• Available water resources are rapidly depleting. 

• Good water quality is found in  the upper hilly regions and sparsely populated areas of the country's main rivers  .

• In the plains, river water is intensively used  for agricultural, drinking, domestic and industrial purposes.

• The concentration of pollutants in rivers is very high during the summer season because water flow is low at that time. 

• The Central Pollution Control Board (CPCB)  in collaboration with the State Pollution Control Boards (SPCs)  are monitoring the national water resource quality at 507 stations. 

• The data obtained from these stations indicate  that biological and bacterial contamination is the main source of pollution in rivers.

1. Yamuna River between Delhi and Etawah is the most polluted river in the country. 

2. Other polluted rivers are Sabarmati in Ahmedabad,  Gomti in Lucknow, Kali in Madurai

3. Musi in Hyderabad  is Ganga in Kanpur and Varanasi. 

• Ground water pollution is caused by the concentration of heavy/toxic metals, fluorides and nitrates in various parts of the country. 

• Statutory provisions, such as the Water (Prevention and Control of Pollution) Act 1974 and the Environment Protection Act 1986,  have not been implemented effectively. 

• The result was that in 1997, 251 polluting industries were set up on the banks of rivers and lakes. 

Water Cess Act 1977

• Which also aims to reduce pollution, but its effect was limited. 

• There is a need to spread  awareness about the importance of water and the effects of water pollution  .

• Through public awareness and participation,  agricultural activities and domestic and industrial discharges 

• The pollutants emitted can be reduced very effectively.

Recycling and reusing water

• Recycling and reuse are other methods  by which the availability of fresh water can be improved. 

• The use of lower quality water, such as treated wastewater, is an attractive option for industries and 

• By using it for cooling and fire-fighting they can reduce the cost on water. 

• Similarly, in urban areas,  water used for bathing and washing utensils can be used for gardening.

• Water used for washing vehicles  can also be used for gardening.  This will conserve good quality water for drinking purposes. 

• Currently, water recycling has been done to a limited extent.  However, the usefulness of water replenished through recycling is widespread.

watershed

• The aim of watershed management is to bring balance between natural resources and society. 

• The success of the watershed system mainly depends on the cooperation of the community.

• The central and state governments have launched several watershed development and management programmes in the country. Some of these are also run by non-governmental organisations.

Greenery

• 'Hariyali' is a watershed development project promoted by the Central Government  with the objective of enabling the rural population to conserve water for drinking, irrigation, fisheries and  afforestation. 

• The project is being executed by Gram Panchayats with the cooperation of the people.

  

Neeru-Meeru  Program 

• Under the Neeru-Miru (Water and You) Programme (in Andhra Pradesh) and Aravari Pani Sansad (in Alwar, Rajasthan), various water storage structures like percolation ponds, lakes (johads) have been excavated and check dams constructed with the cooperation of people. 

• In Tamil Nadu, it has been made mandatory to build water storage structures in homes. No building can be constructed without building a water storage structure. 

benefits of rainwater harvesting 

• In some areas, watershed development projects have been successful in rejuvenating the environment and the economy. 

• There is a need to create awareness among the people in the country by telling them the benefits of watershed development and management 

• Rainwater harvesting is the method of capturing and storing rainwater for various uses. 

• It is a low cost and eco-friendly method 

• Through which rainwater is collected in tube wells, pits and wells to conserve every drop of water. 

• Rainwater harvesting increases water availability,  prevents depletion of groundwater levels,  improves groundwater quality by reducing contaminants such as fluoride and nitrates,  prevents soil erosion and flooding

• Various communities in the country have been harvesting rainwater using various methods for a long time. 

• In rural areas, traditional rainwater harvesting is done in surface harvesting reservoirs like lakes, ponds, irrigation ponds etc. 

• In Rajasthan, rainwater harvesting structures known as Kund or Tanka (a covered underground tank) are  constructed near the house or village to collect and store rainwater inside the house. 

National Water Policy - 2012

The aim of National Water Policy – ​​2012 is to conserve the country's water resources,  develop water resources and manage them better. 

 

Salient features of National Water Policy 

• Emphasis on the need for a National Water Framework Act, a comprehensive legislation for the development of rivers and river valleys. 

• to achieve safe drinking water and sanitation, food security,  support poor people who depend on agriculture for their livelihood 

• The emphasis is on adaptation strategies to climate change for the design and management of water resources structures.

• To ensure efficient use of water, a system of benchmarking water use for various purposes should be developed, i.e. water footprinting and water auditing.

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