Grim headlines like “Dying Dead Sea. Water Scarcity, Climate crisis in Jordan”, “Amid rising temperatures, Karachi faces acute water shortage”, “Sanctuary in Karnataka battles water scarcity as temperatures continue to rise”, “Taps run dry in Cape Town”, etc. serve as painful reminders of the severe crisis most of us are aware of – Water stress!
The above infographic highlights the problem of global water scarcity. Indeed, water scarcity or lack of water resources has now touched every continent in the world. In many regions, however, this is leading to conditions of ‘water stress’, i.e., inability to meet the human and ecological demand for water.
Worst-Affected Regions
17 countries housing about 25% of the world’s population face ‘extremely high’ levels of water stress i.e. more than 80% of their available supply of water is withdrawn every year; as many as 44 countries face ‘high’ levels of water stress i.e. more than 40% of their available supply of water is withdrawn. Therefore, there is a narrow gap between supply and demand, which may constrict further due to periods of less rainfall or drought. The majority of these 17 highly water-stressed countries are in the Middle East and North Africa (MENA).
Why is it Happening?
Shortage of water could be due to physical water scarcity, or economic water scarcity, or a combination of both. Physical water scarcity is caused when the water (supply) sources are unable to meet the demands of a particular region. This could be due to a variety of causes including increased consumption, climate change and overuse or wastage of water.
Thomas Malthus, an 18th Century economist cum demographer, had stated that ‘population multiplies geometrically and food arithmetically. Eventually in the future, there would not be enough food for the whole of humanity to consume and people would starve.’ The same seems to hold true for water. World population has been increasing exponentially over the past couple of centuries, as has industrial development. It is but natural that as population, urbanisation and industrial growth increase, so does water consumption and demand. Physical water reserves, however, have been unable to keep up with this increased consumption. This supply-demand gap is expected only to worsen with time.
Climate change is making the world warmer; therefore the world's hot regions are getting even hotter. At the same time, ‘Hadley Cell expansion’ [1], a climate-change driven phenomenon is causing clouds to move away from the equator toward the poles. This deprives equatorial regions like sub-Saharan Africa, the Middle East and Central America of rainfall.
Inefficient agricultural practices, like flood irrigation, and water-intensive industrial processes, like wet cooling at thermal power plants, use more water than necessary. Additionally, while the available water is getting polluted at an alarming rate, not even a fraction of it is getting treated. As a result, as much as 80% of the world's wastewater is discharged back into the environment without further treatment or reuse, making it unfit for consumption.
In some places, while water availability may be adequate, lack of the necessary monetary means to mobilise water leads to water scarcity. This ‘economic water scarcity’, characterised by insufficient investment in infrastructure to supply, store and distribute water equitably, is prevalent in much of sub-Saharan Africa.
So are we headed for a world with no water?
From the data, statistics and indicators, it would appear so. Existing water resources cannot match the ever-increasing demand for water. But all is not lost, yet. There have been encouraging instances of countering water scarcity as well. Israel, a small country in a semi-arid region, was water scarce in the 1950s, but is now water-surplus. This has been possible due to a combination of resolute policy-making and use of innovative technology. Over the decades, Israeli innovators and entrepreneurs have pioneered cutting-edge drip irrigation, desalination and water treatment technologies. Today, Israel reclaims 80% of its wastewater for agricultural use and is a global leader in water-use efficiency.
Another success story is that of Singapore. At the time of its independence in 1965, with no natural source of fresh water supply, it was entirely dependent on its neighbour Malaysia for its water supply. Singapore, however, is now meeting most of its fresh water demand internally. This has been possible through simultaneous demand and supply side management and an integrated water supply strategy including harnessing of rainwater, recycling and reuse of wastewater (branded NEWater) and desalination. While the country still has to import water, above-mentioned efforts have made it self-sufficient to a great extent.
Therefore, we can conclude that though water stress is indeed a serious problem, if all stakeholders i.e. individuals, entrepreneurs, corporates, academia and governments are sensitive to it and decide to resolve it, it can indeed be reversed. Also, the need of the hour is not only conservation of existing water resources but also execution of ‘out of the box’ technologies to generate new sources of water.
Benjamin Franklin quoted, “When the well’s dry, we know the worth of water.” We need to recognise the worth of water now so that we can indeed prevent our well from running dry!
References:
[1] The Hadley Cell is the most prominent tropical circulation feature. Model projections indicate that the Hadley Circulation will shift its downward branch poleward in both the Northern and Southern Hemispheres, causing drying in the subtropics as a result.
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