01 · Explore
India's Water Resource Profile
Water is a cyclic resource, yet its freshwater component is extremely limited and under increasing stress due to population growth and over-utilisation.
While approximately 71 per cent of the Earth's surface is covered by water, freshwater accounts for only about 3 per cent of the total. In India, the geographical distribution of this resource is highly uneven. India possesses about 2.45 per cent of the world's surface area and 4 per cent of the world's water resources, but it must support more than 17 per cent of the global population.
The total annual precipitation in India is estimated at 4,000 cubic km. The availability from surface water and replenishable groundwater is 1,869 cubic km. Due to topographical, hydrological, and other constraints, only about 60 per cent of this available water can be put to beneficial use. This brings the total utilisable water resource in the country to 1,122 cubic km.
The scarcity of water is becoming a major challenge, leading to disputes between communities and states. Efficient assessment and conservation are no longer optional but necessary for sustainable development.
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What percentage of the world's water resources does India possess compared to its share of the world's population?
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02 · Explore
Surface Water Resources
Surface water is primarily found in rivers, lakes, ponds, and tanks, with river basins serving as the main catchment areas.
India has approximately 10,360 rivers and tributaries longer than 1.6 km each. The mean annual flow in these basins is estimated at 1,869 cubic km, but only about 690 cubic km (32 per cent) of the available surface water can be utilised. This limitation is due to the seasonal nature of rainfall, which is concentrated in the monsoon months, and the topographical challenges of storing and diverting water.
River basins like the Ganga, Brahmaputra, and Barak have huge catchment areas and receive high precipitation. Consequently, while these basins cover only one-third of the country's area, they account for 60 per cent of the total surface water resources. In contrast, while much of the flow in South Indian rivers like the Godavari and Krishna has been harnessed, the potential of the Brahmaputra and Ganga basins remains under-utilised.
Lagoons and backwaters also form significant surface water resources in states like Kerala, Odisha, and West Bengal. Although this water is often brackish, it is vital for fishing and irrigating specific crops like coconut and certain paddy varieties.
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Why is only 32 per cent of India's available surface water utilised?
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03 · Explore
Groundwater Resources
Groundwater is a vital replenishable resource, but its extraction levels vary significantly across Indian states.
The total replenishable groundwater resources in India are approximately 432 cubic km. The level of utilisation is highest in the north-western region and parts of South India. States like Punjab, Haryana, Rajasthan, and Tamil Nadu have very high groundwater utilisation rates, often exceeding their recharge capacity.
In contrast, states like Chhattisgarh, Odisha, and Kerala utilise only a small fraction of their groundwater potential. Others, such as Gujarat, Uttar Pradesh, and Bihar, show moderate usage. Over-exploitation in high-use states has led to a declining water table and serious environmental issues.
For example, over-withdrawal in Rajasthan and Maharashtra has increased fluoride concentrations in groundwater. In parts of West Bengal and Bihar, it has led to increased arsenic concentrations, rendering the water hazardous for human consumption.
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What are the environmental consequences of over-exploiting groundwater in states like West Bengal and Rajasthan?
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04 · Explore
Water Demand and the Role of Irrigation
Agriculture is the largest consumer of water in India, driven by the need for food security in an agrarian economy.
India's water demand is dominated by irrigation, which accounts for 89 per cent of surface water and 92 per cent of groundwater utilisation. This high demand stems from the spatio-temporal variability of rainfall. Large parts of the country, such as North-western India and the Deccan Plateau, are drought-prone and receive insufficient rain for year-round farming.
Irrigation makes multiple cropping possible and significantly increases agricultural productivity. High-yielding varieties (HYV) of crops require a regular and assured moisture supply, which only developed irrigation systems can provide. This was a cornerstone of the Green Revolution's success in Punjab, Haryana, and Western Uttar Pradesh.
Certain crops like sugarcane, rice, and jute have extremely high water requirements, making irrigation indispensable even in areas with relatively high rainfall, especially during dry spells or monsoon breaks.
Sectoral Water Utilisation in India
- 1
Agriculture
Dominates usage: 89% of surface water and 92% of groundwater.
- 2
Domestic Sector
Higher share in surface water (9%) compared to groundwater.
- 3
Industrial Sector
Lowest current share: 2% of surface water and 5% of groundwater.
The distribution of water usage across different sectors in India, showing the heavy reliance of agriculture on both surface and groundwater.
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Why is irrigation essential for the success of Green Revolution crops?
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05 · Explore
Deterioration of Water Quality
Water quality refers to the purity of water, and its degradation limits the availability of usable resources.
Water pollution occurs when foreign substances like micro-organisms, chemicals, and industrial wastes enter water bodies. These pollutants can be dissolved or suspended, harming aquatic ecosystems and often seeping into groundwater. Major rivers generally have better quality in their upper hilly reaches, but quality deteriorates sharply in the plains due to intensive human activity.
The Central Pollution Control Board (CPCB) monitors water quality across the country. Data shows that organic and bacterial contamination is the primary source of river pollution. The Yamuna is identified as the most polluted river in India, particularly between Delhi and Etawah. Other severely affected rivers include the Sabarmati at Ahmedabad and the Ganga at Kanpur and Varanasi.
Legislative measures like the Water (Prevention and Control of Pollution) Act 1974 and the Environment Protection Act 1986 have been enacted, but their implementation has often been ineffective, as evidenced by the continued presence of hundreds of polluting industries along major water bodies.
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Which river is considered the most polluted in India and in which stretch?
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06 · Explore
Watershed Management and Conservation
Watershed management is an integrated approach to managing all natural and human resources within a hydrological unit.
Watershed management involves the efficient conservation of surface and groundwater through methods like percolation tanks, recharge wells, and check dams. Its broader goal is to achieve a balance between natural resources (land, water, plants) and the community. Success depends heavily on community participation.
Several government and NGO-led programs exist. 'Haryali' is a central government project executed by Gram Panchayats to enable rural populations to conserve water for drinking and irrigation. Other notable programs include 'Neeru-Meeru' in Andhra Pradesh and 'Arvary Pani Sansad' in Alwar, Rajasthan, which involved constructions of water-harvesting structures such as percolation tanks and dug out ponds (Johad).
Tamil Nadu has taken a pioneering step by making rainwater harvesting structures compulsory for all buildings. No new construction is permitted without these structures, ensuring long-term groundwater recharge.
Ralegan Siddhi Case Study
Community Participation + Watershed Management = Prosperity
In Ralegan Siddhi, Maharashtra, villagers under the leadership of Anna Hazare transformed a poverty-stricken area. They banned open grazing and water-intensive crops (like sugarcane) and used voluntary labour to repair percolation tanks. This led to a rise in the water table and agricultural self-sufficiency.
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What is the primary objective of the Haryali project?
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07 · Explore
Rainwater Harvesting Techniques
Rainwater harvesting is a low-cost, eco-friendly method of capturing and storing rainwater to recharge aquifers and bridge the demand-supply gap.
Rainwater harvesting involves guiding rain from rooftops or open spaces into borewells, pits, or wells. This practice increases water availability, prevents soil erosion, and improves groundwater quality by diluting contaminants like nitrates and fluorides. In coastal areas, it is particularly useful for arresting saltwater intrusion into freshwater aquifers.
Traditional methods vary by region. In rural Rajasthan, communities build 'Kunds' or 'Tankas' (covered underground tanks) to store water. In urban areas, where demand often exceeds supply, harvesting is essential to reduce dependence on municipal water and save energy used for pumping groundwater.
Beyond harvesting, other remedies for India's water crisis include the desalinisation of water in coastal regions and the proposed inter-linking of rivers to transfer water from surplus to deficit areas.
- 1
Capture rainwater from rooftops or catchment areas.
- 2
Filter the water to remove debris and large particles.
- 3
Direct the water through pipes into a storage tank or recharge pit.
- 4
Allow the water to percolate into the ground to recharge the aquifer or use it directly for non-potable domestic needs.
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What are 'Kunds' or 'Tankas'?
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08 · Explore
National Water Policy and Jal Kranti Abhiyan
The Indian government has framed policies and campaigns to ensure water security through a unified national perspective.
The National Water Policy 2012 emphasizes treating water as an economic good to promote conservation, after meeting basic needs for drinking and sanitation. It advocates for a national water framework law and stresses community participation in managing water services. It also highlights the need for 'water footprints' and water auditing to track efficiency.
The Jal Kranti Abhiyan (2015-16) was launched to ensure water security through per capita availability. Key features include the creation of 'Jal Grams' (selecting one water-stressed village in each of the 672 districts) and the identification of model command areas of about 1000 hectares in different parts of the country. It also focuses on pollution abatement and the construction of arsenic-free wells.
The Atal Bhujal Yojana (Atal Jal) is another significant initiative targeting 8,220 water-stressed Gram Panchayats. It aims to bring about behavioral changes in communities, shifting the focus from consumption to smart water management and conservation.
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What is a 'Jal Gram' under the Jal Kranti Abhiyan?
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According to the National Water Policy 2012, how should water be treated to promote conservation?
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