Simply put: Water scarcity is when there is not enough clean water available to meet a local population’s needs.
By most forecasts, the global population is growing fast. A growing population needs more water. We use it to drink, to bathe, to grow our crops and in all sorts of industrial processes like making textiles and leather, paper and steel. But, currently, there simply isn’t enough of it to sustain us moving forward. Why is that, you might ask, given that over 70% of the world’s surface is water?
The answer lies in the difference between salinated and desalinated, or freshwater. Salinated ocean water contains too many salts and bacteria to be digested safely by humans, and although we can get rid of them through chemical processes, this costs around 15 times as much money as simply transporting local freshwater sources to populations that need them. That doesn’t mean it’s impossible: in fact, Kuwait meets its entire water supplies by converting salt water to freshwater – but Kuwait is one of the richest countries in the world by GDP per capita, as well as one of the smallest. Part of the World Bank’s Water Strategy is to encourage the uptake of desalination plants globally so that we can meet our growing water needs.
According to the World Bank, the world may face a 40% shortfall of supply of clean water by 2030, which is not far off.
Most of the freshwater we get is from aquifers. Aquifers are underground caverns where water has collected over centuries through rainfall. Many of these aquifers are being depleted at a rate faster than they can be refilled naturally, and once the water in them reaches below a certain level, they may not refill at all. Plus, warmer weather often means less rainfall in the areas where aquifers have formed. Many cities and towns in the USA rely on them for drinking water and have formed a project to manually inject drinking water back in to aquifers to ensure they stay working for future generations.
The vast majority – 70% – of our freshwater today is used in agricultural production. Irrigated crops like rice and cotton take up a lot of water. There’s a hidden trade in water called the virtual water economy which we’ll talk more about next time.
By 2050, with an additional 2 billion people on the planet, that figure will need to rise to 112% of our current water supplies. Most of that population growth will be in South Asia and sub-Saharan Africa, regions which are already suffering from water scarcity. Either we need somehow to create new water, or we need to change our agricultural and consumption habits.
Water scarcity fuels conflict, and can make drastic weather events such as floods and droughts more likely. All this puts a big question mark over how we get freshwater to be where it needs to be so that we all get adequate access, now and in future.
Sources: World Bank and UNESCO
Image: “Water Scarcity” by Alejandro Peters is licensed with CC BY 2.0. To view a copy of this license, visit https://creativecommons.org/licenses/by/2.0/