Water Resource Notes in English Class 10 Geography Chapter 3 Book-Contemporary India

 

Water scarcity and the need for water conservation and management

• As soon as we talk about water scarcity, we immediately think of areas with low rainfall or drought-stricken areas.

• Images of the desert of Rajasthan and women balancing pots full of water and walking long distances to fetch water immediately get painted in our minds. 

• It is true that due to annual and seasonal variations in rainfall, the availability of water resources varies over time and space. 

• Most of the water scarcity is caused due to its overexploitation, excessive use and unequal distribution of water among different sections of the society.

• Water scarcity is the result of excessive and growing population and the resulting increasing demand for water and its unequal distribution. 

• Water is needed not only for domestic use for the larger population but also to grow more food. 

• To increase the production of grains, irrigated area can be increased only by exploiting water resources and farming can be done even in dry season. 

• Water is used the most in irrigated agriculture. 

• There is now a need to revolutionise agriculture by developing dry farming techniques and drought resistant crops.

• India experienced rapid industrialisation and urbanisation, and opportunities for development arose. 

• Due to the increasing number of industries, pressure on fresh water resources is increasing. 

• Apart from huge amount of water, industries also require energy to run them and this is largely supplied by hydropower.

• Due to the increasing number of cities and population, not only has the need for water and energy increased but other problems related to these have also arisen. 

• If you look at urban housing societies or colonies, you will find that tube wells have been installed inside them for water supply.

Jal Jeevan Mission

• By announcing this, the Government of India has given priority to improving the quality of life and making the living easier for the people living in rural areas. 

• Objective:- To enable every rural household to have assured supply of potable piped water at a service level of 55 litres per capita on a regular basis on a long-term basis. 

Multi-purpose river projects and integrated water resources management

• Archaeological and historical records show that since ancient times, excellent water works such as dams, embankments of reservoirs or lakes and canals have been constructed from stones and rubble for irrigation. 

• Traditional dams used to collect river and rainwater and later make it available for irrigation of fields. 

• Nowadays dams are also used for power generation, domestic and industrial use, water supply, flood control, recreation, inland navigation and fisheries.

• Therefore dams are also called multipurpose projects where multiple uses of the collected water are coordinated. 

• For example, the Bhakra Nangal project in the Sutlej-Beas basin is used for both hydropower generation and irrigation.

• Multipurpose projects were seen as a vehicle to take the country on the path of development and prosperity by overcoming the obstacles created during the colonial period. 

• Jawaharlal Nehru proudly called dams the 'temples of modern India'. 

• He believed that through these projects, agriculture and rural economy, industrialization and urban economy would develop in a coordinated manner.

Damage caused by the dam  

• Damming rivers and controlling their flow obstructs their natural flow, which reduces sediment flow and causes excess sediment to accumulate at the bottom of the reservoir, making the river bed more rocky and causing a lack of food in river aquatic life habitats. 

• Dams divide rivers into pieces, thereby obstructing the movement of aquatic animals in the rivers, especially during the spawning season. 

• When reservoirs are built in flood plains, the vegetation and soil present there get submerged in water and get decomposed over time.

• Irrigation has changed the cropping pattern in many areas where farmers are moving towards water-intensive and commercial crops. 

• This can have serious ecological consequences such as salinization of soils. 

• Pradhan Mantri Krishi Sinchai Yojana ensures access to some means of protective irrigation to all agricultural farms in the country, bringing the desired rural prosperity

• Dams are built for flood control but they cause flooding when sediments accumulate in their reservoirs. 

• In case of excessive rainfall, even big dams sometimes fail to control floods.

• These floods not only caused loss of life and property but also caused large-scale soil erosion. 

• The deposition of sediment in the dam's reservoir also means that this sediment, which is a natural fertiliser, does not reach the flood plains, leading to land degradation problems. 

• Multipurpose projects also increase the possibility of earthquakes and excessive use of water causes water-borne diseases, bacterial diseases in crops and pollution.

Atal Ground Water Scheme 

• It is being implemented in 8220 water stressed Gram Panchayats in 229 administrative blocks/talukas of 80 districts in seven states, Gujarat, Haryana, Karnataka, Madhya Pradesh, Maharashtra, Rajasthan and Uttar Pradesh. 

• The selected States account for about 37 per cent of the total number of water stressed (severely exploited, severe and semi-critical) blocks. 

• One of the key aspects of Atal Jal is to change the behaviour of the public from the existing attitude of water use towards water conservation and judicious water management.

Water works in ancient India

• An excellent water storage system was built at Shringavera near Allahabad, a century before Christ, to conserve the flood water of the River Ganges.

• During the time of Chandragupta Maurya, dams, lakes and irrigation systems were constructed on a large scale.

• There is evidence of excellent irrigation systems in Kalinga (Orissa), Nagarjunakonda (Andhra Pradesh), Bennur (Karnataka) and Kolhapur (Maharashtra).

• Bhopal Lake, one of the largest artificial lakes of its time, was built in the 11th century.

• In the 14th century, Iltutmish built the Hauz Khas (a special pond) for water supply in the Siri Fort area of ​​Delhi.

Krishna-Godavari dispute

• The dispute began with the Maharashtra government constructing a dam on the Koyna river for a hydroelectric project, and the Karnataka and Andhra Pradesh governments objected to this. 

• This will reduce water flow in the lower reaches of the river in these states and will adversely affect agriculture and industry.

Prime Minister's Agricultural Irrigation Scheme

Objective: 

• Increasing the actual availability of water on the farm  

• Expanding the sown area under assured irrigation, 

• Reducing wastage 

• Improving on-farm water use efficiency to increase availability

• Adoption of irrigation and other water saving technologies 

• Adoption of sustainable water conservation systems etc.

Sardar Sarovar Dam

• Sardar Sarovar Dam is built on the Narmada River in Gujarat.

• This is a major water resources project of India which involves four states – Maharashtra, Madhya Pradesh, Gujarat and Rajasthan. 

• Sardar Sarovar Project will fulfill the water needs of drought-prone and desert areas. 

• Sardar Sarovar Project will provide irrigation facility to 18.45 lakh hectare area of ​​3112 villages in 15 districts of Gujarat. 

• This will also irrigate 2,46,000 hectares of strategically important desert districts of Barmer and Jalore in Rajasthan and 37,500 hectares of land in tribal hilly areas of Maharashtra through lift. 

• About 75 per cent of the command area in Gujarat is drought prone while in Rajasthan the entire command area is drought prone. 

• Assured water availability will soon make the region drought-proof.

rainwater harvesting

• Due to controversies arising over multipurpose projects, rainwater harvesting can be a practical alternative.

• In ancient India, along with excellent aquatic constructions, water storage structures were also found. 

• People had deep knowledge about rainfall patterns and soil properties. 

• They have developed many methods of harvesting rainwater, groundwater, river water and flood water as per the local ecological conditions and their water requirements. 

• In hilly and mountainous regions, people have constructed channels like 'Gul' or 'Kul' (Western Himalayas) by changing the course of the river flow to irrigate the fields. 

• The method of 'rooftop rainwater harvesting' was common in western India, especially Rajasthan, to collect rainwater. 

• In the flood plains of West Bengal, people used to build flood water channels to irrigate their fields. 

• In arid and semi-arid areas, pits were dug in the fields to collect rainwater so that the soil could be irrigated and the conserved water could be used for farming. 

• 'Khadin' in Jaisalmer district of Rajasthan and 'Johad' in other areas are its examples.

• In the semi-arid and arid areas of Rajasthan, especially in Bikaner, Phalodi and Barmer, almost every house used to have underground tanks or 'tanka' to store drinking water. 

• Its size can be as big as a large room. 

• A house in Phalodi had a tanka measuring 6.1 m deep, 4.27 m long and 2.44 m wide. 

• Tankas are an integral part of the well-developed rooftop rainwater harvesting system here, which is built inside the main house or in the courtyard. They are connected to the sloping roofs of the houses by pipes. 

• Rainwater from the roof passed through these pipes to the underground tank where it was collected. 

• The first rain water was not collected. The rain water that came after that was collected.

• This makes it a water source providing drinking water even during water-scarce summers. 

• Rainwater or 'palar paani' as it is called in these areas, is considered to be the purest form of natural water. 

• In some houses, underground rooms are also built along with tanks because this source of water keeps these rooms cool as well, providing relief from heat in summers.

• In western Rajasthan, the practice of rooftop rainwater harvesting is declining due to the availability of perennial drinking water from the Indira Gandhi Canal. 

• Some homes still have the facility of tankers because they do not like the taste of tap water. 

• Even today this method of water conservation and storage is being used in many rural and urban areas of India. 

• In Gandachoor, a remote village located in Mysore district of Karnataka, the villagers have made arrangements for rooftop rainwater harvesting to meet their water needs at home. 

• Around 200 houses in the village have this facility and this village has earned the fame of rain water rich village. 

• The village receives about 1,000 mm rainfall every year and with 10 fillings, the storage efficiency is 80 per cent. 

• Each household here can collect and use approximately 50,000 m³ of water each year. 

• Approximately 1,000,000 litres of water is collected every year by 200 households.

Bamboo Drip Irrigation System

• This 200 year old method is prevalent in Meghalaya.  

• In this, water from rivers and springs is collected through pipes made of bamboo and is carried to a distance of hundreds of meters.

• Finally the flow of water is reduced to 20 to 80 drops per minute and released on the plant.

• Tamil Nadu is one state where it has been made mandatory to have rooftop rainwater harvesting structures in every house across the state. 

• In this context, legal action can be taken against the guilty persons. Rooftop rainwater harvesting is prevalent in Shillong, the capital of Meghalaya. 

• This is interesting because Cherrapunji and Mawsynram, which receive the highest rainfall in the world, are located just 55 kilometres from Shillong and the city faces severe problem of drinking water shortage. 

• Almost every house in the city has a rooftop rainwater harvesting system. 

• About 15-25 percent of the total domestic water demand is met through rooftop water storage system.