There is nothing more imperative to life on earth than water – yet multiple countries on all its continents are experiencing extreme water shortages signalling a global water crisis. Of the world’s 20 megacities, fourteen are experiencing water scarcity or drought conditions – with as many as four billion individuals living in regions that experience severe droughts for at least one month a year.
As natural disasters and climate change strike, along with the world’s growing population, humanity faces a growing challenge of too much water in some places and not enough in others. So what is the current state of the world’s water resources and what threats do the human race face due to depleted water resources?
Earth’s water resources
The Earth’s hydrosphere contains approximately 1.4 million cubic kilometres (km3 ) of water, however, only a percentage of this water is fit for crop production or human and animal consumption. Roughly 90,000km3 of water a year can be accessed easily, which is less than 0.5% of the total freshwater accessible. 2.5% of the world’s water is fresh, of this roughly 69% is inaccessible in glaciers, ice caps or permanent snow cover and 30% is stored underground with the rest being found in rivers, lakes, and reservoirs. In essence, only 0.007% of Earth’s water is used to feed its eight billion people – presenting the root of the water scarcity on this planet. The demand for water An individual needs between 50 – 100 litres of water a day for basic health and sanitation, with a further 400,00 litres needed through food consumption. Water consumption across the globe is grossly unevenly spread – with countries such as the United States consuming more than eight times the average domestic water use and four times the average for food production. Increasing competition has arisen between countries and sectors within these countries for water, with demand originating from four main sources; agriculture, production of energy, industrial uses, and human consumption. Production of crops and livestock is water‐intensive, and agriculture alone accounts for 70% of all water withdrawn by the combined agriculture, municipal and industrial (including energy) sectors. The booming demand for livestock products, in particular, is increasing the demand for water, as global demand for food is expected to increase by 70% by 2050. Global energy consumption is expected to increase by about 50% by 2035 due to population growth and increasing economic activity. As regards human consumption, the main source of demand comes from urban communities requiring water for drinking, sanitation, and drainage – as the population grows, so does the demand for already sparse water. The threat of water scarcity is very real and consequences for the lack of supply can already be seen around the world. Due to limited freshwater supply, 1.1 billion people worldwide lack access to water and 2.4 billion individuals do not have access to basic sanitation – exposing them to diseases such as cholera, typhoid fever, and other water-borne illnesses.
The water systems that help entire ecosystems to thrive and feed the growing human population have become depleted and stressed. Rivers, lakes, and reservoirs around the globe are drying up or becoming too polluted for safe consumption, with over 50% of the world’s wetlands disappearing. Agriculture consumes more water than any other source and wastes much of that through inefficiencies. Climate change is altering patterns of weather and water around the world, causing shortages and droughts in some areas and floods in others. At the current consumption and population growth rate, this situation will only worsen. By 2025, two-thirds of the world’s population may face water shortages and ecosystems around the world will suffer even more – depleting water and food sources further. Countries with high water consumption due to high water theft, malpractice and leakage must be held accountable. Proper water resource management needs to be implemented to guarantee a safe and consumable future water supply – ensuring the cycle of destruction is stopped, to lead to a water plentiful future.
