The Freshwater Resources & Supplies On Earth, & How We Use Them

We’ve already put together a guide about the total amount of water on Earth and how it’s distributed.

However, this guide is specifically about fresh water resources/supplies on Earth, how we use them, and other important considerations such as how we might sustainably manage fresh water resources into the future. 

 

Summary – Freshwater Resources, Supply & Usage Around The World

There are different types of fresh water resources – some are renewable (generally from rainfall), and some are not

Additionally, some fresh water sources some recharge at a very slow or negligible rate (ground water for example tends to have a much slower recharge rate than surface water, taking 5 years or more in some instances to show any meaningful water renewal levels)

Fresh water as a natural resource is distributed unequally geographically around the world – some parts of the world have a lot of it and it’s easily accessible, whilst others don’t have much of it and it may not be easily accessible.

As a result, every city and region faces different challenges with their fresh water supplies

Some cities experiencing water stress or water scarcity problems augment their fresh water supply with technology such as desalination or waste water recycling

Dry and warm regions with low or variable annual rainfall levels, and higher surface temperatures, tend to be some of the more water scarce regions in the world.

This is generally because rainfall and the hydrological cycle (rainfall, evaporation, inflow into surface water sources such as rivers and lakes and eventually into ground water aquifers) tends to be the natural process that refills and renews fresh water resources

The global averages for fresh water withdrawals across the three main sectors are – agriculture (with irrigation playing a significant role) at 70%, industry (particularly wet cooling in thermo electric power plants) at 19%, and municipal (household and public services) at 11%.

But, water share across the three sectors differs between individual countries, and developed vs developing, and high vs low income countries.

Poorer countries tend to use more fresh water for agriculture in general according to ourworldindata.org

There’s many factors that can increase the demand (withdrawal and consumption) on fresh water resources within a city, and can impact the level of fresh water supplies within a city

However, every city and population of people around the world has different ratios of fresh water demand to supply depending on how sustainably governments and water suppliers managed water resources

Three of the biggest global problems or issues relating to fresh water resources are quantity of water available, quality of water available, and access to water

Some countries have much bigger fresh water supplies in terms of total volume than others (Brazil, Russia and the United States are leaders)

Some countries have a much bigger per capita water supply than others

Some countries withdraw freshwater at much higher volumes or per capita rates than others – China, India and the US are the top withdrawing countries by volume

There’s a difference between fresh water withdrawal, and consumption.

Withdrawal can include returning water back after use to it’s source such as a river or lake, whilst consumption includes water that is used and isn’t returned back to the source

There’s also a difference between potable drinking water, and non potable fresh water that is used for other uses such as irrigation for agriculture

In terms of trends with freshwater use – rates of global freshwater use have increase six fold since the year 1900, and increased sharply from the 1950s onwards, but since 2000 slowed somewhat (up to 2019 at least)

Nevertheless, fresh water usage and demand is expected to increase in the future as populations grow, more countries become developed, and demand grows for water intensive products like fossil fuels and meats, as well as energy generation and biofuels

The trends we see for some major countries right now is a slow decline in renewable internal freshwater resources per capita, which in part is impacted by withdrawal rates

India is one example of a country that fits this description – extracting a lot of water for irrigation for agriculture. Brazil is another.

 

Salt Water vs Fresh Water vs Drinking Water On Earth: How Much Of Each There Is, & How It’s Distributed

Read more in this guide about the volumes and distributions of the different types of water on Earth’s surface.

As we can see, there is far less fresh water than salt water on Earth’s surface.

There is even less fresh water once water trapped in ice and snow is taken into account.

Of the accessible and available fresh water resources, they are distributed unequally by nature in different volumes in different countries (some countries have far higher natural fresh water resources than others, and when taking into account how wet or dry a country’s climate is, some water resources refill or recharge much quicker and more consistently than others).

It’s worth reading the ‘the71percent.org’ resource in the above guide which outlines how fresh water specifically is distributed across the world.

Apart from natural fresh water resources, potable and non potable fresh water can be generated from man made technology such as desalination and atmospheric water generation, and even from waste water or storm water when used or poor quality water is treated and recycled.

 

Different Types Of (Natural) Freshwater Sources

There’s two main types of natural fresh water resources on the Earth’s surface:

1. Surface Water

Water found in lakes, rivers, dams (dams are technically man made) and above ground sources

Surface water tends to be more renewable (from the natural hydrologic cycle) and recharges at a much quicker rates compared to ground water.

This is because surface water sources and natural catchments (that filter into surface water sources) receive rain water inflow and are renewed from rainfall that isn’t evaporated or transpired by plant life.

 

– Ground Water

Water found in below ground aquifers.

Ground water tends to recharge at much slower and sometimes negligible rates on the human time scale – it can take 5 years or longer to see meaningful changes in some ground water sources.

Ground water can suffer from ground water depletion from over withdrawing, and, some ground water can also be brackish/saline and may or may not be able to be treated and used (so, quality of the water resource must be considered).

For these reasons, some ground water resources are referred to as non renewable.

 

You can read more about the different sources of fresh water in this guide.

FAO.org also explains the different types of freshwater sources in this guide 

 

Augmenting Fresh Water

Populations can augment their natural water supplies with technology such as desalination, waste water and run off water recycling and re-use, ground water replenishment, and other methods.

On a smaller scale, technology like atmospheric water generators might be used to in some instances to produce fresh water and drinking water

Rainwater harvesting is also a method of making more fresh water available

 

Internal vs Shared, Transboundary & External Water Sources

Internal fresh water sources that belong to a State or country should be differentiated from shared, or transboundary and external fresh water sources.

Shared, transboundary or external fresh water sources may be involved in water trade, and water import/export

 

Countries With The Most Fresh Water Resources – By Volume

According to Wikipedia.org, total freshwater supplies in kilometres cubed (km3) for the countries with the most internal fresh water resources are:

1. Brazil – 8233

Russia – 4508

United States – 3069

Canada – 2902

China – 2840

Colombia – 2132

European Union – 2057

Indonesia – 2019

Peru – 1913

India – 1911

Democratic Republic Of The Congo – 1283

Venezuela – 1233

Bangladesh – 1227

Myanmar – 1168

15. Nigeria – 950

Wikipedia.org shows an extended list of the top 172 countries here 

WorldAtlas also describes where most of the freshwater in each of these countries is found.

For example, the Amazon region contains over 70% of the fresh water in Brazil.

 

Countries With The Most Fresh Water Resources – Per Capita

According to Food and Agriculture Organization, AQUASTAT data, and via Indexmundi.com, renewable internal freshwater resources (internal river flows and groundwater from rainfall) per capita (in cubic metres person) worldwide are as follows:

Greenland – 10,662,190.00

Iceland – 519,264.70

Guyana – 315,695.80

Suriname – 180,680.70

PNG – 103,277.80

Bhutan – 100,457.50

Gabon – 87,433.42

Canada – 80,181.04

Solomon Islands – 77,671.05

Norway – 74,359.11

New Zealand – 72,510.37

Peru – 52,981.02

Chile – 50,244.70

Congo – 45,574.91

Liberia – 45,550.44

Colombia – 44,882.07

Belize – 43,389.99

Vanuatu – 38,632.41

Panama – 34,989.88

Fiji – 32,230.53

 

Countries That Withdraw The Most Fresh Water (By Volume, & Per Capita)

Freshwater Withdrawals, By Volume

Per OurWorldInData.org, in 2014, the biggest users of freshwater were:

India – over 760 billion cubic metres per year.

China – just over 600 billion m

United States – 480 to 490 billion m3

Pakistan – 183.5 billion m3

Indonesia – 113.3 billion m3

 

Freshwater Withdrawals, Per Capita, Per Year

Per OurWorldInData.org, in 2010, the biggest users of freshwater per person were:

Iceland – 11,042 cubic metres (per person, per year)

Turkmenistan – 5,753 cubic metres

Chile – 2152 cubic metres

Uzbekistan – 2106 cubic metres

 

Fresh Water Withdrawals Per Capita By Region

Per OurWorldInData.org … Average per person, per year, renewable freshwater withdrawal rates by region are as follows (in cubic metres):

South America – 30,428

Oceania – 29,225

Eastern Europe – 21,383

North America – 12,537

Central America and Caribbean – 8,397

Western & Central Europe – 4,006

Sub Saharan Africa – 3,879

 

Freshwater Withdrawals By Sector – Right Now

The main sectors responsible for fresh water withdrawals globally are agriculture, industry, and municipal.

What we see is that different regions and countries across the the world withdraw fresh water resources in different amounts across each sector.

There can be differences for individual countries, but also developed and developing countries, as well as high and low income countries.

The general averages across the sectors though are (according to various sources) – 70 percent of freshwater withdrawals for agriculture, 19 percent of total water withdrawals are used for industrial purposes, and 11 percent of withdrawals are used for municipal purposes [and the] majority of countries use less than 30 percent of withdrawals for domestic purposes

 

Agriculture (& Irrigation)

Per OurWorldInData.org: 

[Water used in agriculture can be rain fed, or pumped irrigation]

[Water is used for] food crop, livestock, biofuels, or non crop production

[India is the largest user of agricultural water, and China is second for agricultural water withdrawals]

[The average agricultural water use for low-income countries is 90 percent; 79 percent for middle income and only 41 percent at high incomes]

… [Some countries like] Germany and the Netherlands use less than one percent of water withdrawals for agriculture

[Irrigation levels differ across the world, and irrigation is] particularly prevalent across South & East Asia and the Middle East; Pakistan, Bangladesh and South Korea all irrigate more than half of their agricultural area. India irrigates 35 percent of its agricultural area.

 

Per globalagriculture.org:

Irrigation provides approximately 40% of the world’s food, from an estimated 20% of agricultural land, or about 300 million hectares globally.

Almost half of the total area being irrigated worldwide is located in Pakistan, China and India, and covers 80%, 35% and 34% of the cultivated area respectively.

 

In the US, agriculture accounts for 38 percent of the nation’s freshwater withdrawals but it accounts for approximately 80 to 90 percent of the nation’s consumptive water use (water that is evaporated, or otherwise removed from the watershed).

– watercalculator.org

 

Industry

Per OurWorldInData.org: 

Industry water use involves industrial applications such as … dilution, steam generation, washing, and cooling of manufacturing equipment. [It also includes] cooling water for energy generation in fossil fuel and nuclear power plants (hydropower generation is not included in this category), or as wastewater from certain industrial processes.

The United States is the largest user of industrial water, withdrawing over 300 billion m³ per year. … [and] China is the second largest, at 140 billion m³

Rates are typically much lower across Sub-Saharan Africa and some parts of South Asia

… industrial water tends to dominate in high-income countries (with an average of 17 percent), and is small in low-income countries on average 2 percent.

 

Industry accounts for nearly 20% [of fresh water withdrawals] … and there are indications this demand will rise.

In advanced economies as much as 45% of all water demand is generated by industry.

– ge.com

 

In industrialized nations … industries consume more than half of the water available for human use.

Belgium, for example, uses 80% of the water available for industry.

– worldometers.info

 

Worldwide, high-income countries use 59 percent of their water for industrial use, while low-income countries use 8 percent

– cdc.gov

 

Municipal (Households & Public Services)

Per OurWorldInData.org: 

[Defined as water use] for domestic, household purposes or public services.

[Examples include water we use for] drinking, cleaning, washing, and cooking.

… China’s domestic water demands are highest at over 70 billion m³ per year [and] India … is the third largest municipal water user.

The United States, despite having a much lower population, is the second largest user as a result of higher per capita water demands.

Domestic uses of water withdrawals can also dominate in some countries across Europe with high rainfall …

 

Freshwater Withdrawals By Sector – Future Projections

Pacinst.org also has a graphic which shows both the global water withdrawal and water consumption volumes, by sector, by the year 2040.

Agriculture by far has the highest withdrawal and consumption rates.

The graphic is available at pacisnt.org

 

Individual Industries That Use The Most Water

Read more in this guide which summarizes which individual industries within the different sectors that use the most water – directly, and indirectly.

 

Water Withdrawn vs Water Consumed – There’s A Difference

Sustainabilityreport.duke-energy.com defines water withdrawn vs water consumed as:

‘Water withdrawn is the total volume removed from a water source such as a lake or river. Often, a portion of this water is returned to the source and is available to be used again. Water consumed is the amount of water removed for use and not returned to its source’.

 

Variables & Factors That Can Affect Available Natural Freshwater Resources & Supplies

There’s three main global fresh water problems that can impact available fresh water supplies in an area – quantity related problems, quality related problems, and access related problems.

Each one of these categories of problems has different factors and variables to consider.

Read more about global fresh water problems in this guide.

 

Are We Using More Or Less Freshwater Over Time?

There are global averages for fresh water usage/withdrawal trends, and then trends and stats for each individual country, each State or province, and each city or town.

 

Globally, there is a ‘fresh water withdrawals since the year 1900’ graph available at ourworldindata.org

A growing global population and economic shift towards more resource-intensive consumption patterns means global freshwater use … has increased nearly six-fold since 1900.

Rates of global freshwater use increased sharply from the 1950s onwards, but since 2000 appears to be plateauing, or at least slowing.

[Evidence of that can be seen by looking at 2004 where the global population used 3.85 trillion cubic metres of freshwater, and 2014 where the global population used 3.99 trillion cubic metres of freshwater]

– OurWorldInData.org

 

From worldometers.info:

Freshwater withdrawals have tripled over the last 50 years.

Demand for freshwater is increasing by 64 billion cubic meters a year (1 cubic meter = 1,000 liters)

[Some of the reasons for these increases might be:]

The world’s population is growing by roughly 80 million people each year.

Changes in lifestyles and eating habits [are more water intensive]

The production of biofuels has … increased sharply in recent years [and it’s water intensive]

Energy demand is also accelerating, with corresponding implications for water demand.

 

You can view a live global water use counter here (worldometers.info)

 

Forecast For Water Use In The Future

Specifically with agriculture and energy related water usage:

– By 2050, the global water demand of agriculture is estimated to increase by a further 19% due to irrigation needs (globalagriculture.org)

– As the world’s population reaches 9 billion, demand will require a 50 percent increase in agricultural production and a 15 percent increase in … water withdrawals. By 2035, the world’s energy consumption will increase by 35 percent, which in turn will increase water use by 15 percent and consumption by 85 percent (worldbank.org)

 

Per Capita Renewable Fresh Water Resources Are Declining Across Major Countries

According to OurWorldInData:

[… many major countries’ per capita renewable fresh water resources are declining as replenishment slows or isn’t moving quick enough, and populations grow]

[Brazil by far has the biggest per capita supply decrease from 1962 to 2014, going from over 70,000 cubic metres of water, to under 30,000 cubic metres]

[In that same time span, the United States has gone from 15,106 cubic metres to 8,845 cubic metres]

[China has gone from 4,225 cubic metres, to 2,016 cubic metres]

 

At worldometers.info, if you click through to India’s data for example, you can see a decrease in per capita renewable fresh water resources since 1962.

 

Will We Have Enough Fresh Water In The Future? (To 2050 & Beyond)

This guide summarises some factors that may impact whether we will have enough fresh water resources in the future.

 

Sources

1. Hannah Ritchie and Max Roser (2018) – “Water Access, Resources & Sanitation”. Published online at OurWorldInData.org. Retrieved from: ‘https://ourworldindata.org/water-use-stress’ [Online Resource]

2. http://www.fao.org/docrep/005/y4473e/y4473e06.htm

3. https://www.worldatlas.com/articles/countries-with-the-most-freshwater-resources.html

4. https://en.wikipedia.org/wiki/List_of_countries_by_total_renewable_water_resources

5. https://www.indexmundi.com/facts/indicators/ER.H2O.INTR.PC/rankings

6. http://www.fao.org/docrep/005/y4473e/y4473e08.htm#TopOfPage

7. https://web.archive.org/web/20150612123716/https://www.cia.gov/library/publications/the-world-factbook/fields/2201.html

8. http://www.worldometers.info/water/

9. https://www.ge.com/reports/global-thirst-water-use-industry/

10. https://www.cdc.gov/healthywater/other/industrial/index.html

11. https://pacinst.org/worlds-water-challenges-2017/

12. https://sustainabilityreport.duke-energy.com/2008/water/withdrawal.asp

13. https://www.worldbank.org/en/news/feature/2014/01/16/will-water-constrain-our-energy-future

14. https://www.globalagriculture.org/report-topics/water.html

15. https://www.watercalculator.org/water-use/foods-big-water-footprint/

16. https://www.bettermeetsreality.com/will-we-have-enough-usable-water-in-the-future-what-will-happen-if-we-dont-have-enough-the-future-of-freshwater-for-humans-society/

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