Global Decline in Freshwater Reserves | 22 Nov 2024

Source: BS 

Why in News? 

Recent data from National Aeronautics and Space Administration (NASA)- German GRACE (Gravity Recovery and Climate Experiment) satellites reveal a significant decline in Earth's total freshwater levels since 2014.

What is the Status of Decline in Freshwater Reserves? 

• Global: Between 2015 and 2023, freshwater stored on land, including lakes, rivers, and groundwater, fell by 1,200 cubic kilometres. 
  • Half of the world’s countries have degraded freshwater systems, with over 400 river basins experiencing declining water flows, including iconic watersheds like the Congo Basin. 
  • The World Meteorological Organization reports that 2023 marked the driest year in over three decades for rivers globally, exacerbating the freshwater crisis. 
• India: Home to 18% of the global population, India has just 4% of the world's freshwater resources and occupies only 2.4% of Earth's surface. Nearly half of its rivers are polluted, and over 150 primary reservoirs are at just 38% of their storage capacity, exacerbating the country’s severe water crisis. 
  • The 2018 Composite Water Management Index by NITI Aayog (National Institution for Transforming India) indicates that a significant portion of India's population faces high to extreme water stress, with approximately 600 million Indians experiencing water scarcity..  
  • Groundwater depletion is a major concern, especially in agrarian states like Punjab and Haryana, where overexploitation for irrigation and domestic use has caused water tables to drop significantly. 
  • Areas in central and western India, including Rajasthan, Maharashtra, and Gujarat, are frequently hit by droughts, further depleting already strained water reserves. 

What are the Causes for the Decline in Freshwater Levels? 

• Role of El Niño Events: The 2014-2016 El Niño event, one of the most significant since 1950, disrupted rainfall patterns globally. 
  • Warmer Pacific Ocean temperatures shifted atmospheric jet streams, intensifying drought conditions worldwide. 
• Effects of Climate Change: Climate change has caused irregular and uneven rainfall patterns, resulting in prolonged dry spells, droughts, and erratic monsoon seasons. 
  • Intense precipitation events caused surface runoff instead of groundwater replenishment. Prolonged dry periods compact soil, reducing its water absorption capacity. 
  • Climate change amplifies evaporation and increases atmospheric water-holding capacity, worsening drought conditions. 
    • Droughts have significantly affected regions such as Brazil, Australasia, North America, Europe, and Africa. 
• Over-extraction of Groundwater: Over-reliance on groundwater for irrigation, particularly in areas with inadequate rainfall, has led to its depletion, as extraction often exceeds natural replenishment.  
  • Additionally, industries and urban centres that depend on groundwater further exacerbate the depletion. 
• Loss of Ecosystems:  Destruction of natural ecosystems, such as wetlands and forests, reduces the ability of the land to retain water.  
  • The loss of forest cover leads to soil erosion, which reduces the ability of the land to absorb rainwater, further decreasing the replenishment of water bodies. 
• Agricultural Practices and Pollution: Agriculture consumes 70% of the world’s accessible freshwater, but inefficient irrigation methods and the cultivation of water-intensive crops lead to significant water waste. 
  • Industrial waste and untreated wastewater also contribute to the pollution of water bodies, with long-term impacts on water quality and availability. 

What are the Implications of Freshwater Decline? 

• Impact on Biodiversity: The World Wildlife Fund (WWF) reports an 84% decline in freshwater species since 1970, driven by habitat loss, pollution, and migration barriers like dams.  
  • These factors destabilise ecosystems, threatening biodiversity and their essential services. 
• Impact on Human Communities: The 2024 UN report on water stress highlights that reduced water availability strains farmers and communities, leading to famine, conflicts, poverty, and a higher risk of waterborne diseases.  
  • Water scarcity also hampers industries, affecting economic development and job creation. By 2025, 1.8 billion people may experience "absolute water scarcity," a crisis worsened by rapid population growth, inefficient water use, and poor governance. 
  • Urban areas are not immune to water stress. Many cities in India including Chennai, and Bengaluru, have faced severe water shortages in recent years, disrupting daily life and leading to increased costs for water transportation and management. 
• Ecosystem Services: Freshwater ecosystems support nutrient cycling, boosting agricultural productivity. Wetlands also help mitigate flooding and enhance climate resilience.  
  • Their degradation threatens these vital services, reducing both environmental and community stability. 
• Geopolitical Conflicts: Over 60% of global freshwater is shared by two or more countries. The decline in these resources, whether due to droughts, over-extraction, or pollution, can lead to disputes over water rights and usage.   
  • Water scarcity can worsen political tensions, as seen in the Nile River dispute between Egypt, Sudan, and Ethiopia.  
    • Ethiopia's construction of the Grand Ethiopian Renaissance Dam has raised concerns in Egypt over its water supply, potentially escalating into broader conflicts.  
  • Similarly, in India, disputes over river water sharing, such as those involving the Indus Water Treaty (IWT) with Pakistan and the inter-state conflicts over the Cauvery and Krishna rivers,have led to ongoing conflicts between states. 
• Science and Technology:  The decline in freshwater resources impacts Artificial Intelligence (AI) systems, which rely on water for cooling data centres.  
  • By 2027, AI is estimated to consume 4.2 to 6.6 billion cubic metres of water annually, increasing pressure on already limited water supplies. 

Way Forward

• Policy Reorientation: Countries need to treat water as a common good, reorienting public policies on water pricing, subsidies, and procurement to encourage conservation, especially among heavy water users. 
  • Ensuring vulnerable communities have access to clean water and sanitation is critical to addressing water-related inequalities. 
• Rainwater Harvesting: Rainwater harvesting systems, both large and small, offer a practical solution to supplement freshwater supplies, particularly in water-scarce regions. 
• Optimise Desalination: Desalination, though energy-intensive and costly, provides a solution to water scarcity in coastal areas.  
  • Energy-efficient technologies like reverse osmosis should be optimized to reduce costs and environmental impacts. Additionally, nanotechnology-based devices can be developed for efficient water purification with less energy-intensive processes.  
• Infrastructure Development: Optimising infrastructure like dams, stepwells, reservoirs,  and aqueducts can improve water storage and distribution, but careful planning is needed to avoid environmental and social issues.  
  • New dam projects should prioritise ecological restoration, sediment management, and equitable water distribution. 
• Bottled Water Alternatives: Sustainable alternatives like water filters and refillable containers should be promoted to reduce bottled water demand and encourage eco-friendly consumption.