GCSE Geography | Global Demand for Water (Resource Management - Water 1)

97.5% of all water found on Earth is found in seas and oceans so therefore is salt water that can't be used unless it goes through the expensive process of desalinisation. This means that only 2.5% of global water is freshwater - and in fact only about 20% of total freshwater is available to use, as the majority it is in the form of glaciers and ice sheets.

So what do we need water for?

• About 69% is used in agriculture - crop irrigation and drinking water for livestock
• About 20% is used in industry - for processing/manufacturing, but also as an ingredient in many food and drink products
• About 6% is domestic use (in the home) - drinking/cooking, bathing/showering, flushing toilets, washing machines/dishwashers
• Energy use - generating hydroelectric power (HEP) and cooling in other power stations
• Leisure use - e.g. outdoor water sports, swimming pools, water needed in hotels, artificial watering of golf courses, etc

The global pattern

Unfortunately across the world there is a gap between supply and demand for water - there are places where the water supply exceeds the demand (water surplus) and places where the demand for water exceeds the supply (water deficit). There are many areas suffering from serious water deficit issues, which are said to be experiencing water stress - which is the temporary inability to meet the water needs of the population, either because there is not enough water, or the water is poor quality (following contamination).

Water scarcity - the lack of fresh water resources to meet the standard water demand.

Water security - having reliable access to a sufficient quantity of clean water (when people don't have this they are said to be experiencing water insecurity).

Most countries suffering from water scarcity are in the southern hemisphere - there is plenty of fresh water in the northern hemisphere (which is dominated by HICs), where large areas across Asia and Africa suffer water stress where they struggle to meet the water needs of their populations, and are largely LICs and NEEs. Many of these countries are also bordering hot deserts so are areas where rainfall totals are low. Most of Europe and South America have water security for the majority of the time, but can be at risk of water insecurity in times of drought.

There is also water inequality within countries. For example in the UK - the north and west has a water surplus due to high rainfall, lower evaporation rates and plenty of potential reservoir sites, and has a relatively low population density. Whereas the south and east has a water deficit. This is the most densely populated part of the country and has the lowest annual rainfall. Another example is Nigeria in Africa, where access to water is much higher in the south of the country, with areas in the north experiencing desertification.

Why has the global demand for water increased?

Population growth

The first and main reason is global population growth - in 1950 the world's population was estimated to be around 2.5 billion people, increasing to around 6 billion by 1998, and 7 billion in 2010. On 15th November 2022 the global population hit 8 billion, which was considered a huge milestone in human development - taking just 12 years to increase by 1 billion people. The global population is predicted to hit 9 billion in 2037 - taking 15 years to increase by another billion, which does show that overall population growth is starting to slow down.

However, we need to remember that the countries with the highest level of population growth are those countries that are already struggling with resources, and are already experiencing food, water and energy insecurity, so therefore population growth is likely to lead to more people suffering from water stress as the demand for water for domestic use increases. Countries with the lowest Gross National Income (GNI) per capita also tend to have the highest fertility rates. This means that global population growth is mainly concentrated in the poorest countries - usually in sub-Saharan Africa. In fact, population growth across the whole of Africa is 2.5% per year, compared to 0.1% in Europe.

Economic development

The second reason is economic development. As countries start to develop economically the population will have more money to spend on better housing which may have baths and showers, as well as flushing toilets. They may also have water intensive domestic appliances such as washing machines, which will drive up the domestic demand for water. Economic development will also see investment into 'thirsty' manufacturing industries that use huge amounts of water in production, and a shift from subsistence agriculture to commercial farming, which uses a significant amount of water for irrigation. As wealth increases, so does the demand for water, and HICs have been consuming huge amounts of water for these reasons for many decades.