Outdoor landscape of mountain reservoir body of water.

(January 27, 2026) Water is one of Earth’s most essential resources. It regulates climate, keeps our bodies running, and supports everything from farms to factories. From surprising science facts to insights about conservation, agriculture, and human use, here are 100 amazing water facts that will make you see every drop in a whole new way.

Earth’s Water Supply and Distribution

  1. There is about the same amount of water on Earth now as there was millions of years ago.9
  2. Earth holds about 1.386 billion cubic kilometers of water.39
  3. Of all the water on the planet, about 2.5 – 2.75 % is freshwater, and an even smaller fraction — around 0.3 % — is surface water in rivers and lakes that people use most directly.48
  4. Only roughly 0.014 % of all water on Earth is both fresh and easily accessible in surface and near-surface sources that people can use directly.49
  5. More than 68 % of freshwater is stored in ice sheets and glaciers, making these frozen reservoirs the planet’s largest freshwater pool.50
  6. About 30 % of freshwater is stored as groundwater in aquifers below the surface.51
  7. Antarctica and Greenland together hold the vast majority of the world’s ice-bound freshwater, but human-accessible fresh water is spread across glaciers, groundwater, lakes and rivers.52
  8. Roughly 2.1 % of all Earth’s water is frozen in glaciers and ice caps — a bigger share than older figures suggested.51
  9. The length of the side of a cube which could hold the Earth’s estimated total volume of water in km = 1150.10

Glaciers, Ice and Frozen Water

  1. Water expands by 9% when it freezes.8
  2. The freezing point of water lowers as the amount of salt dissolved in it increases. With average levels of salt, seawater freezes at -2 °C (28.4 °F).2
  3. In Washington state alone, glaciers provide 1.8 trillion liters (470 billion gallons) of water each summer.32
  4. In a 100-year period, a water molecule spends 98 years in the ocean, 20 months as ice, about 2 weeks in lakes and rivers, and less than a week in the atmosphere.31
  5. A 2.6-billion-year-old pocket of water was discovered in a mine, 2 miles below the earth’s surface.41
  6. In 2023, glaciers lost more than 600 gigatons of water, the largest mass loss registered in the last five decades.61

Water Science and Physical Properties

  1. Water can dissolve more substances than any other liquid including sulfuric acid.1
  2. Hot water can freeze faster than cold water under some conditions (commonly known as the Mpemba effect).22
  3. Water weighs about 8 pounds a gallon.5
  4. Water regulates the Earth’s temperature.23
  5. Water is the most common substance found on earth.31

Water and the Human Body

  1. Water makes up about 66 percent of the human body.33
  2. 70% of the human brain is water.5
  3. Children in the first 6 months of life consume seven times as much water per pound as the average American adult.11
  4. A person can live about a month without food, but only about a week without water.8
  5. Each day, we also lose a little more than a cup of water (237 ml) when we exhale it.17
  6. Drinking too much water can be fatal (known as water intoxication).33
  7. There are no scientific studies that support the recommendation to drink 8 glasses of water per day.33
  8. It takes about 12 gallons per day to sustain a human (this figure takes into account all uses for water, like drinking, sanitation and food production).16

Water Use in the United States

  1. In the United States, total water withdrawals were about 322 billion gallons per day (2015 USGS estimate).47
  2. In 2015, thermoelectric power accounted for 133 billion gallons per day, about 41% of total US withdrawals.47
  3. In one year, the average American residence uses over 100,000 gallons (indoors and outside).1
  4. Americans drink more than one billion glasses of tap water per day.11
  5. The United States draws more than 40 billion gallons (151 million liters) of water from the Great Lakes every day—half of which is used for electrical power production.12
  6. The average cost for water supplied to a home in the U.S. is about $2.00 for 1,000 gallons, which equals about 5 gallons for a penny.8
  7. Americans use 5.7 billion gallons per day from toilet flushes.15
  8. Flying from Los Angeles to San Francisco, about 700 miles round-trip, could cost more than 9,000 gallons of water.25
  9. 1/3 of what the world spends on bottled water in one year could pay for projects providing water to everyone in need.4
  10. Refilling a half-liter water bottle 1,740 times with tap water is the equivalent cost of a 99-cent water bottle at a convenience store.15

Household Water Use and Waste

  1. The average family of four uses 180 gallons of water per day outdoors. It is estimated that over 50% is wasted from evaporation, wind, or overwatering.20
  2. It takes about 70 gallons of water to fill a bathtub.25
  3. The average pool takes 22,000 gallons of water to fill.24
  4. A swimming pool naturally loses about 1,000 gallons (3,785 liters) a month to evaporation.28
  5. A water-efficient dishwasher uses as little as 4 gallons per cycle, but hand-washing dishes uses 20 gallons of water.20
  6. If everyone in the US flushed the toilet just one less time per day, we could save a lake full of water about one mile long, one mile wide and four feet deep.30
  7. If everyone in the US used just one less gallon of water per shower every day, we could save some 85 billion gallons of water per year.30
  8. It takes seven and a half years for the average American residence to use the same amount of water that flows over the Niagara Falls in one second (750,000 gallons).34

Leaks and Infrastructure Loss

  1. 1 in 6 gallons of water leak from utility pipes before reaching customers in the US.15
  2. Household leaks waste nearly 1 trillion gallons of water annually nationwide.53
  3. About 10% of homes have leaks that waste 90 gallons or more per day.54
  4. A leaky faucet that drips at the rate of one drip per second can waste more than 3,000 gallons per year.37
  5. Up to 50% of water is lost through leaks in cities in the developing world.6
  6. On average, 10 gallons per day of your water footprint (or 14% of your indoor use) is lost to leaks.24

Agriculture, Food and Water Footprints

  1. Agriculture remains the largest water-using sector globally, accounting for about 70% of freshwater withdrawals worldwide.55
  2. Of the estimated 1.4 billion hectares of crop land worldwide, around 80 percent is rainfed and accounts for about 60 percent of global agricultural output (the other 40% of output is from irrigated crop land).36
  3. 40% of freshwater withdrawals in the United States are used for agriculture.29
  4. Freshwater withdrawals for agriculture exceed 90% in many countries: Cambodia 94%, Pakistan 94%, Vietnam 95%, Madagascar 97%, Iran 92%, Ecuador 92%.29
  5. About 6,800 gallons of water is required to grow a day’s food for a family of four.3
  6. 1 pound of beef requires 1,799 gallons of water.43
  7. 1 gallon of wine requires 1,008 gallons of water.43
  8. A 0.3-pound burger requires 660 gallons of water.43
  9. 1 slice of bread requires 11 gallons of water.43
  10. 1 apple requires 18 gallons of water.43
  11. 1 pound of chocolate requires 3,170 gallons of water.43
  12. To create one pint of beer it takes 20 gallons of water.3
  13. Over 42,000 gallons of water (enough to fill a 30×50-foot swimming pool) are needed to grow and prepare food for a typical Thanksgiving dinner for eight.31
  14. It takes 120 gallons of water for one egg.5
  15. A jellyfish and a cucumber are each 95% water.5
  16. Chicken and goat are the least water intensive meats to consume.21
  17. It takes more than twice the amount of water to produce coffee than it does tea.21
  18. An acre of corn will give off 4,000 gallons of water per day in evaporation.31

Water and Production

  1. 300 tons of water are required to manufacture 1 ton of steel.15
  2. Producing a gallon (3.79 liters) of corn ethanol consumes 170 gallons (644 liters) of water in total, from irrigation to final processing. On the other hand, the water requirement to make a gallon of regular gasoline is just five gallons (19 liters).28
  3. 500 sheets of paper require 1,321 gallons of water.43

Global Water Access and Inequality

  1. As of 2024, about 2.1 billion people still lacked safely managed drinking water.56
  2. Diarrheal disease kills about 444,000 children under 5 each year, and a significant share is preventable through safe drinking water, sanitation and hygiene.57
  3. 40 billion hours are spent collecting water in Africa alone.7
  4. Women and girls collectively spend an estimated 200 million hours every day collecting water.58
  5. In Nairobi, the urban poor pay 10 times more for water than in New York.6
  6. 80% of all illness in the developing world is water related.6
  7. $260 billion is the estimated annual economic loss from poor water and sanitation in developing countries.7
  8. 65% of freshwater withdrawals in China are used for agriculture.29
  9. 85% of the world population lives in the driest half of the planet.13
  10. 263 rivers either cross or demarcate international political boundaries.35
  11. Various estimates indicate that, based on business as usual, ~3.5 planets Earth would be needed to sustain a global population achieving the current lifestyle of the average European or North American.13

Water Scarcity, Stress and the Future

  1. Around 4 billion people experience severe water scarcity at least one month each year.59
  2. A recent UN University report described a shift toward “global water bankruptcy,” warning that large parts of the world are now living beyond sustainable water supplies.60
  3. Water use has grown at more than twice the rate of population increase in the last century.26
  4. Thirty-six states are anticipating water shortages by 2016.14
  5. Groundwater occurs almost everywhere beneath the land surface. The widespread occurrence of potable groundwater is the reason that it is used as a source of water supply by about one-half the population of the United States.44
  6. Hydrologists estimate, according to the National Geographic Society, U.S. groundwater reserves to be at least 33,000 trillion gallons — equal to the amount discharged into the Gulf of Mexico by the Mississippi River in the past 200 years.45
  7. There have been 265 recorded incidences of water conflicts from 3000 BC to 2012.21
  8. At any given moment, groundwater is 20 to 30 times greater than the amount in all the lakes, streams, and rivers of the United States.45
  9. About 27 trillion gallons of groundwater are withdrawn for use in the U.S. each year.46
  10. The High Plains Aquifer covers eight states and 175,000 miles.46
  11. There is more fresh water in the atmosphere than in all the rivers on the planet combined.34
  12. In some countries, less than half the population has access to clean water.7
  13. Three quarters of all Americans live within 10 miles of polluted water.27

Water Beyond Earth

  1. NASA has discovered water in the form of ice on the moon.40
  2. Each cubic foot of Martian soil contains around two pints of liquid water, though the molecules are not freely accessible, but rather bound to other minerals in the soil.38
  3. If all the water vapor in the Earth’s atmosphere fell at once, distributed evenly, it would only cover earth with about an inch of water.34

References

1. http://water.epa.gov/learn/kids/drinkingwater/water_trivia_facts.cfm
2. http://www.sciencekids.co.nz/sciencefacts/water.html
3. http://www.water.siemens.com/en/about_us/Pages/Water_Footprint.aspx
4. http://blueplanetnetwork.org/water/
5. http://www.fs.usda.gov/Internet/FSE_DOCUMENTS/stelprdb5303137.doc
6. http://www.cnn.com/SPECIALS/road-to-rio/secret-life-drinking-water
7. http://fieldnotes.unicefusa.org/infographic-world-water-crisis
8. http://water.epa.gov/learn/kids/drinkingwater/waterfactsoflife.cfm
9. http://dnr.wi.gov/org/caer/ce/eek/earth/conserve.htm
10. http://www.brita.net/blue_wonder.html
11. http://www.baycountyfl.gov/water/facts.php
12. http://aqua.wisc.edu/waterlibrary/Default.aspx?tabid=74
13. http://www.unwater.org/water-cooperation-2013/water-cooperation/facts-and-figures/en/
14. http://www.campusrec.illinois.edu/goGreen/facts.html
15. http://images.fastcompany.com/magazine/154/infographic/water-world.html
16. http://science.howstuffworks.com/environmental/earth/geophysics/run-out-of-water.htm
17. http://science.howstuffworks.com/environmental/earth/geophysics/h2o.htm
18. http://www.ifad.org/english/water/key.htm
19. http://www.worldwatercouncil.org/fileadmin/world_water_council/documents_old/Library/WWVision/Chapter3.pdf
20. http://awesome.good.is/transparency/web/1204/your-daily-dose-of-water/flash.html
21. http://pacinst.org/publication/10-shocking-facts-about-worlds-water/
22. http://math.ucr.edu/home/baez/physics/General/hot_water.html
23. http://www.waterwise.org.uk/pages/fun-facts.html
24. http://environment.nationalgeographic.com/environment/freshwater/water-conservation-tips/?rptregcta=reg_free_np&rptregcampaign=20131016_rw_membership_r1p_us_se_w
25. http://environment.nationalgeographic.com/environment/freshwater/water-conservation-tips/?rptregcta=reg_free_np&rptregcampaign=20131016_rw_membership_r1p_us_se_w
26. http://environment.nationalgeographic.com/environment/freshwater/freshwater-crisis/
27. https://donate.nationalgeographic.org/SSLPage.aspx?pid=1071
28. http://www.scientificamerican.com/article/top-10-water-wasters/
29. http://data.worldbank.org/indicator/ER.H2O.FWAG.ZS
30. http://www.sandiego.gov/water/conservation/kids/funfacts.shtml
31. http://www.cleanwaterways.org/kids/fun_facts.html
32. http://nsidc.org/cryosphere/glaciers/quickfacts.html
33. http://www.scientificamerican.com/article/strange-but-true-drinking-too-much-water-can-kill/
34. http://www.afcec.af.mil/shared/media/document/AFD-130322-056.pdf
35. http://www.transboundarywaters.orst.edu/publications/atlas/atlas_html/interagree.html
36. http://www.fao.org/ag/save-and-grow/en/5/index.html
37. http://www.epa.gov/WaterSense/pubs/fix-leak.html
38. http://www.theguardian.com/science/2013/sep/26/nasa-curiosity-rover-mars-soil-water
39. https://www.usgs.gov/water-science-school/science/how-much-water-there-earth
40. http://www.cnn.com/2009/TECH/space/11/13/water.moon.nasa/index.html?iref=24hours
41. http://www.livescience.com/32028-oldest-water-found-underground.html
42. http://online.wsj.com/news/articles/SB123483638138996305
43. http://environment.nationalgeographic.com/environment/freshwater/embedded-water/
44. http://pubs.usgs.gov/circ/circ1186/html/gen_facts.html
45. http://www.ngwa.org/Fundamentals/use/Pages/Groundwater-facts.aspx
46. http://www.groundwater.org/get-informed/facts.html
47. https://www.usgs.gov/faqs/how-much-water-used-people-united-states
48. https://genaq.com/percentage-of-water-on-earth
49. https://en.wikipedia.org/wiki/Water_scarcity
50. https://education.nationalgeographic.org/resource/earths-fresh-water
51. https://www.usgs.gov/faqs/how-much-earths-water-stored-glaciers
52. https://www.grida.no/resources/5608
53. https://www.epa.gov/watersense/fix-leak-week
54. https://19january2017snapshot.epa.gov/www3/watersense/pubs/fixleak.html
55. https://www.unwater.org/news/fao-2025-aquastat-water-data
56. https://www.who.int/news/item/26-08-2025-1-in-4-people-globally-still-lack-access-to-safe-drinking-water—who–unicef
57. https://data.unicef.org/topic/child-health/diarrhoeal-disease
58. https://www.unicefusa.org/what-unicef-does/childrens-health/water-sanitation/safe-water-projects/girls-water-burden
59. https://www.unicef.org/wash/water-scarcity
60. https://www.reuters.com/sustainability/climate-energy/looming-water-supply-bankruptcy-puts-billions-risk-un-report-warns-2026-01-20
61. https://library.wmo.int/records/item/69033-state-of-global-water-resources-report-2023