Uses of water, rising demand and water shortages

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Uses of water, rising demand and water shortages

Uses of water

Water consumption worldwide has dramatically increased, from 1.22 trillion cubic meters in 1950 to over 4 trillion cubic meters in 2018. This escalation is more than double the population growth rate during the same period.

Analysing the global water usage by different sectors reveals that agriculture is the leading consumer, accounting for 69% of total water use. The industrial sector comes next, using 19% of the global water supply. Domestic usage, which includes household consumption, is at 12%.

We see stark contrasts when we look at water consumption patterns between developed and developing countries. In developing nations, agricultural usage dominates, making up more than 80% of total water consumption, with a large portion dedicated to irrigation. On the other hand, in developed countries, while agriculture and industry remain significant users, there has been a marked increase in water demand for recreational activities.

Rising demand for water

Since the 1950s, global water use has tripled, driven by several factors, including population growth, improved living standards, dietary shifts from grain-based to protein-based diets, increasing urbanisation, and a surge in industrial water demand.

Increasing waters supply

The ultimate goal of all water supply methods is to transport water from its source to its place of use. As of 2015, about 91% of the world’s population had access to piped water supply, a significant increase from 76% in 1990. However, over 660 million people lack access to an improved water source. This amplified water consumption has largely been facilitated by investments in water infrastructure, such as dams and reservoirs. In some countries, water is delivered daily to urban areas yet connected to the main supply network.

Areas of water shortage

Regions Facing Water Scarcity Water shortage is most acute in the Middle East, North Africa, Central Asia, and Northern India. The bulk of the Earth’s precipitation is either inaccessible or distributed unevenly. Arid regions, which cover 40% of the world’s land area, receive only 2% of global rainfall. Water scarcity, related to the availability of drinkable water, threatens global food supplies, impedes economic and social development, and can lead to severe conflicts among countries sharing drainage basins.

Water scarcity is when the water supply drops below 1000 cubic meters per person per year, placing a country under water stress. If the water supply falls below 1000 cubic meters per person per year, a country experiences water scarcity for all or part of the year.

Water stress is when the demand for water resources exceeds the available resources, or the quality is too poor to use. A country is said to experience water stress when its water supply is below 1700 cubic metres per person, per year.

Water depletion hotspots can result from drought, groundwater depletion, ice sheet and glacier loss or retreat, drying of surface water bodies (like the Aral and Caspian Seas), and the filling of large reservoirs (such as the Three Gorges Dam).

Aquifers supply approximately half of the global drinking water, but many have experienced significant declines in their water tables. A notable example is the Ogallala Aquifer in the American Midwest, where the water table has dropped by over 35 meters in the past five decades. This reduction in water levels can lead to serious environmental, economic, and social challenges. For instance, aquifer depletion in China has reduced rice yields in several areas.

Water surplus

Water surplus occurs when the water supply surpasses the demand for it. This typically happens in temperate and tropical humid regions, including significant portions of North America, Western Europe, and the basins of the Amazon and Congo rivers.

Countries and specific regions within countries experiencing a water surplus typically exhibit the following characteristics:

Beneficial geographical factors related to water – they have high rainfall and surface run-off levels, substantial surface water reserves, and sizeable aquifers. Moderate rates of evaporation can also contribute significantly.
They usually have low population density and effective water management strategies (both in terms of quantity and quality).

Summary

Water usage has significantly increased, with agriculture being the largest consumer, and stark differences in usage patterns exist between developed and developing nations.
The demand for water has tripled since the 1950s due to factors like population growth, improved living standards, and increased industrial water demand.
While 91% of the world’s population had access to piped water by 2015, over 660 million people still lack access to an improved water source. This increase in consumption has been facilitated by infrastructural investments.
Regions like the Middle East, North Africa, Central Asia, and Northern India face acute water shortages. In contrast, areas with high rainfall, abundant surface water, and effective water management often experience water surplus.