Question: What is the main cause of water scarcity?
Hypothesis: I think that population growth is the main reason for water scarcity. The reason is because population growth increases the use of water, & some people are careless about saving water. Also, when there are more people, there is more pollution & climate change because of more usage
What is water & the importance of water:
Water is the liquid that makes life on Earth possible. All living things,from tiny bacteria to giant blue whales, need water to survive. Without it, we wouldn’t even be alive! Water is used for almost everything! For food, to drink it, showers, toilets, & MANY more! Water is important because it carries nutrients to all our cells in our body & oxygen to our brain. Water allows the body to absorb and soak in minerals, vitamins, amino acids, glucose and other things. Water purifies the body. It helps to control body temperature. In fact, you can only survive 3-4 days without water! If we didn’t have water or if all the water evaporated, temperatures would become hot, humans & animals would die. Then plants would die. Then, Earth would become somewhat like Venus. Also, if all the water was gone, there may never be life on Earth again because after all, 4 billion years ago, the first life forms that we know of appeared on water!
Water is a very important thing, yet many of us around the world take it for granted. Water is fast becoming even more precious than gold or oil. Earth simply does not have enough usable water to go around. Most of Earth’s water, almost 97% is salty, which we can’t drink or use to water our crops. Only about 3% of Earth’s water is fresh, & most of that is locked away in polar ice caps, glaciers, or underground layers of rock called aquifers.
Will we ever run out of water?
Water never seems to end! It's almost everywhere you go. But is that true? Nope! There are many places in the world where water is scarce & where water is dried up. Take for example; Lake Victoria. In Africa, this lake has dropped many feet, & has actually dried up 2 times already many thousands of years ago! The rainfall in this area is decreasing. Scientist say that in the future, it will be very dry & the rainfall in Lake Victoria area will lessen. Many people in Africa depend on Lake Victoria for food, drink, showers, & many more. Or how about the Aral Sea? Well, this freshwater lake was the 4th largest lake in the world. It was drained for irrigation. So, this lake wasn’t dried up, it was drained. This means this area is very dry now. If more lakes are drained liked this, then we won’t have enough water, & there will be a water scarcity & that might lead to running out of water. If we ever do have very less water, then what will happen is that clean water will be protected, & saved up only for the the people who can afford it. Then the people who could not afford water, will become sick because of contaminated water or even worse, die. So basically, draining rivers are not a very good idea, it's basically going to lessen the freshwater that is available around the world. UNO says that 4 out of 10 people are affected by water scarcity.
What is water scarcity?
When you hear the words “water scarcity”, what comes to your mind? Well, water scarcity is a big problem, especially in developing countries but sometimes, also in developed countries too. In short, you could say that water scarcity is a worldwide problem.
Water scarcity is the shortage of freshwater supplies to meet the normal water needs in a given area. It mostly affects dry & deserted areas, & places where the water is too polluted to drink. It is a social, environmental and economic problem in many countries.
There are two types of water scarcity. Economic & physical water scarcity.
Economic Water Scarcity: Economic water scarcity is the poor management of the drinkable & available water.
Physical Water Scarcity: Physical water scarcity is when water cannot meet all the needs of an area.
Cause of water scarcity:
Today, we can only reach & use 1% of Earth’s freshwater. That 1% is under stress because of 3 major problems; pollution, increased demand (world’s ever-increasing population), & climate change. Water scarcity is also caused by deforestation, uneven distribution of water around the world, natural calamities such as droughts and floods, overuse of aquifers and its consequent slow recharge, overuse & wasting of water. Also poor management & uneducation leads to water scarcity.
Water Scarcity: Cause #1
Pollution comes in many types. One of them is water pollution! Water pollution is caused by the dirtying of water, whether it is throwing garbage, throwing excrement in water, or oil & chemical spills. This makes that certain amount of water undrinkable, & since developing countries cannot handle that because of problems, there will be a water shortage in those countries. Water pollution is a problem on many continents. South America’s Amazon rainforest is about 7 million km² & about 10 million people & more than 30,000 plant species live there. For decades, people have been throwing human waste & toxic chemicals into the Amazon River. These poisons will slowly destroying the jungle ecosystem. In other poor areas where freshwater is not treated, disease-carrying organism grows & makes people sick in many ways. Some examples of diseases are Cholera, food poisoning, Typhoid fever, Giardia, Dysentery & many more.
When people don't have enough running water, they dump their waste outside their houses. Then, the bacteria dirties the water which makes it unusable & when people do use it, they will most likely get diseases or sickness. In Haiti, (the poorest country in the Western Hemisphere), 7 out of 10 people do not have clean water to drink. Each year, waterborne illnesses cause more than half the deaths in Haiti. A massive earthquake hit in 2010, damaging wells & water pipes there, making clean water even more unavailable! Many children & adults have to walk miles to find clean water to drink. In Bangladesh, people have to drink dirty, polluted, untreated water. The water is so polluted that all the fish have died!
Water Scarcity: Cause #2
In 2011, the world’s population reached 7 billion. Experts say, that by 2050, world's population will be 9 billion & the people will be walking the planet, looking for food, energy, land & water. Growing populations reduce the amount of water available for each person. Around 60 years ago, the 2.5 billion people on Earth only used a third of the freshwater we use today! Many people thought of water as an unlimited resource. Today, research shows that more than 1.1 billion people-1 in every 6 people in the world don’t have enough clean water to drink. They live on less than 8 liters a day. Experts say that by 2035, 3.6 billion people will be living in areas where there is less water. In Bangladesh, water pollution is caused in part by poverty & in part by overpopulation. Yet its population is expected to increase quickly to 200 million by 2050-more than 50 million more people than the country holds now. Wealthy countries are less likely to have polluted drinking water because they often have the ways to purify their water & throw away of human waste properly. However, population growth in a wealthy country can lead to water shortages too. One reason is that people in wealthy countries, use more water. In the United States, 4-person family, on average, uses 1514 liters on water a day, or about 379 liter per person. This level of use would be sustainable if only a few people were using the water. Instead, more & more people rely on limited water resources. For example: the Los Angeles population is about 12 million 500,000, yet the area can only support 1 million people on its own water. So Los Angeles & many other cities in the Western United States pull their water from distant rivers. Pulling water is expensive & there is no longer enough river water to go around.
Water Scarcity: Cause #3
Many scientists think that climate change is already affecting people around the world by producing extreme weather conditions such as storms & floods. Yet the threat that climate change presents the global water supply may be the worst threat of all. Scientists predict that by 2050, one-fifth of the world’s population may face a severe water shortage as a result of climate change. Climate change occurs as a result of too much carbon dioxide & other greenhouse gases in the atmosphere.
These gases produced in large parts by the burning of fossil fuels, trap the sun’s heat close to Earth’s surface, like a greenhouse. The result is an overall increase in Earth’s temperature. That warming, in turn, leads to climate change. The warmer temperatures disrupt the water cycle.
Warmer temperatures increase evaporation of surface water into the atmosphere affecting different parts of the world in different ways. Increased evaporation might dry out some areas unlike producing excess precipitation in others. Droughts are long periods of abnormally low precipitation that result in shortage of water. Regions at the highest risk include the Mediterranean & in the Middle East.
In the United States, most scientists say that climate change is responsible for an extreme drought in the Southwest & California. The drought in the South West has been causing problems in the region since 1999. The water level of Lake Mead, on the border between Nevada & Arizona, has dropped to 40%.
The lake which is fed by the Colorado River, is a source of freshwater for about 40 million people.
Scientists say climate change is also responsible for the melting of glaciers high in the Himalayan mountains. The glaciers help provide freshwater for 1.9 billion people living in India, Pakistan, Afghanistan, Nepal, China, Bhutan, Bangladesh, and Myanmar. They use it for drinking, agriculture, energy, or other purposes.
In the past, melting glaciers slowly released water into the stream of the Indus, Ganges, & Brahmaputra Rivers. Now the rapid melting of the glaciers in reducing the water supply. At the same time, the increased glacier melt has caused flooding along each of the 3 rivers.
As climate change worsens, less water is available for producing energy, raising livestock, & growing crops. Wildlife & natural ecosystems suffer. Conflicts break out between cities, states, & even countries over who has the best claim to water.
Tensions over water are growing between India & at least 2 of its neighbors- Pakistan & China. All 3 are racing to build dams on headwaters in the Himalayas that feed important rivers below.
Meanwhile, some countries in Africa argue over who has the best right on the Nile River. In the middle East-one of the driest areas on Earth-some experts predict that the next world war will be over water.
Warmer air can hold more humidity than cold air. This means that if the air gets warmer, the water evaporates, which makes the area dry, & more likely to suffer drought, & weird weather patterns. Also, studies say that the South is expected to get drier and the North is expected to get wetter. This means that the North will obviously have more drinkable water than the South, because water will be dried up there. So, there will be an unequal distribution of water. So if there is climate change, it will lead to problems for countries in the South & sometimes in the North.
Water Scarcity & Deforestation
Forests control the water cycle by balancing precipitation, evaporation and water springs. Forest canopies store and release water vapor, which controls rainfall. Forests can also help reduce the impacts of flood from storms by blocking and slowing down the flow of runoff. Deforestation weakens this process, leading to irregular rainfall patterns including drought and flooding & also decreases the amount of groundwater.
Forests act as a filter to keep pollutants away from water.
In the early 2000s, Colorado had wildfires that destroyed forests. Ash and debris from the fires made its way into the main water sources, forcing Denver's water utility, which served 1.4 million people, to temporarily rely upon reserved water supply. Cleaning up this alone cost Denver’s water utility $26 million.
Crops that use a lot of water:
There are a lot of crops that require a lot water. Here are some of them.
- Alfalfa: This crop is used to feed livestock. Because it contains protein & it is easy to transport. But unfortunately the water amount used to grow this is higher than some other crops. Alfalfa uses 18-36 inches per season.
- Rice: We all have probably ate rice before. Rice grows in paddy fields. This means that rice has to be in a “flooded” area for it to grow which uses a lot of water.
- Almonds: Almonds use a LOT of water. To grow ONE almond, it requires about 1.1 gallons of water! That is a lot of water to grow one almond!
- Cotton: Cotton is what is used to make some clothes you wear. To produce just one kilogram, it takes 5,283 gallons of water!
- Sugarcane: Sugarcanes are sometimes used to make sugar. It needs about 210 liters of water to produce 1 kilogram.
- Wheat: Wheat uses a lot of water & also, it is used for many, many things. To produce 1 kilogram of wheat, we need to use more than 1,800 litres of water.
Animals that use a lot of water:
And it's not just plants that use water, it's also animals. Here are some animals that use water:
- Cows: Cows use a lot of water. They drink about 100 gallons a day!
- Elephants: Elephant’s are the largest land mammal. No wonder they drink about 50 gallons a day!
- Hippo: Hippo’s drink about 56 gallons a day.
- Blue whale: Blue whales are the biggest animal in the world, they drink about 10,000 gallons a day.
HUMANS: We drink a lot of water. Everyday, from all the people in the world combined, we use about 10 billion gallons of water for our everyday needs!
Overuse & wasting of water:
- One of the most common ways in which people waste water is by leaving the water running when brushing their teeth or doing the dishes.
- The water overuse that leads to water scarcity, often happen in areas of irrigation agriculture, harms the environment in several ways including increased salinity, nutrient pollution, and the loss of floodplains and wetlands.
- Taking long showers & baths.
- Using your toilet as an ashtray or wastebasket so it can get clogged & may need to waste a lot of water & money to fix it. Every cigarette butt or tissue you flush away also flushes away five to seven gallons of water.
- Leakage of taps and pipelines. Even a small drip can waste 50 or more gallons of water a day.
- Instead of using broom to clean the sidewalks and steps, using a hose wastes hundreds of gallons of water.
- Ignoring the leaks outside the house, since they don’t mess up the floor or keep us awake at night. However, they can be even more wasteful than inside water leaks, especially when they occur on your main water line.
Uneven disdribution of water:
The distribution of water on the Earth’s surface is extremely uneven. Only 3% of water on the surface is fresh; the remaining 97% is in the ocean. From all the freshwater, 69% is in glaciers, 30% underground, and less than 1% is located in lakes, rivers, and swamps. So, only 1% of the freshwater on the Earth’s surface is usable by humans, and 99% of the usable quantity is situated underground. Also water is not equally distributed around the world. Some countries have more water than others, but most have enough to meet people's needs. What they don’t always have is the way to make that water available to people. Rich developed countries can tap into hard-to-reach sources of water much more easily than poor, developing countries, where people often don’t have enough money and resources to dig wells or build dams to create reservoirs.
Problems of population growth: The number of people around the world is always changing. Everyday, about 220,000 people are born & increased to Earth’s population. Doesn't that seem like a lot? Well it is! Increased population causes many problems but we can’t stop them all because if we tried to reduce the human population, people would basically have to die. Problems that population growth cause are, climate change, poverty, lack of health care, lack of food & drink, deforestation, stress, conflicts over natural resources and many more.
Population growth & water scarcity: For thousand of years, human population grew slowly, but now, it is increasing rapidly. This rise has led to a population explosion in the last two hundred years. This uncontrolled rise in population has quickly increased the demand for water and the pressure on the already scarce resources of Earth. The demand for water for domestic, industrial, agricultural and many more– these have increased in the past few decades. Certain areas have been more affected than others. The areas that mostly have water scarcity are the areas with fewer water resources, like rivers, lakes, streams & more. The little amount of water we can use around the world has brought problems between many nations. A country is classified water scarce if they have less than 1000 cubic meters of renewable freshwater per person for a year. Water scarcity affects population because of the deaths of people from drinking contaminated water or no water at all. The increase in population leads to the increase in demand for freshwater. Also, when there is population growth, more crops & plants have to be grown so people can survive & this uses more water.
Based on one of the Findings of the Worldwatch Institute’s Family Planning and Environmental Sustainability Assessment (FPESA) and based on the recent scientific evidence, we can say that ongoing growth of human population is a bigger cause of water scarcity than climate change.
After 2 years of assessing about 900 scientific papers published in 12 years, FPESA released a report of finding the relationship between family planning & environmental sustainability. Slow population growth means slower increase of pressure on the environment from human activity. And the same applies to the water crisis.
According to United Nations World Report & Population Institute, the connections between a growing population that needs a higher demand for drinking water and water for agriculture shows that the shortages of water that are expected to affect many regions of the world will have severe consequences on the lives of millions of people, and that world leaders will need to find solutions in order to conserve and protect water resources for their countries, or find alternative methods to find new sources of water, such as desalination.
According to WHO, population growth will also increase water pollution. Millions of people don’t have access to safe drinking water, while billions of people don’t have proper water sanitation. Urban areas have a high risk of water pollution as the area is densely populated.
Runoff from streets can carry oils, heavy metals, and other contaminants, while sewage water can leak into groundwater, bringing bacteria, nitrates, phosphorus and other chemicals. Waste dumping also can pollute existing sources of freshwater with hazardous materials and toxic chemicals. It is estimated that between forty to fifty percent of all available freshwater sources on Earth are polluted, and the pollution of groundwater is on the rise.
More urbanization with dense population, lead to more water pollution in urban settings.
In the last few decades, meanwhile, population growth in many or even most water basins has been more dramatic than any changes in climate.
Overpopulation will lead to local and international conflict over control of available quantities on water resources. According to many experts, if there is another world war, it could be over water resources.
Middle Eastern countries, such as Iraq, Iran, Afghanistan, Yemen, and Syria, countries in Africa like Darfur, Sudan, and Somalia, and the South American countries of Peru and Brazil have all experienced conflicts involving scarce water supplies. These conflicts are due to multiple countries relying on a single water source, such as the Shatt al-Arab river between Iran and Iraq. A dispute over water withdrawal from the river was an important factor that caused the Iran-Iraq war in 1980.
The city of Chennai in India faced a huge water crisis in 2019, because 4 of the main reservoirs that supply the city with water dried up due to lack of rainwater and groundwater. The lack of groundwater and rainwater is due to buildings taking up natural space (trees and the natural wetlands of Chennai have decreased due to urbanization), because of the high population, industrialization and Chennai being the sixth largest city in India. Now in 2021, Chennai is looking to its wetlands for water supply.
Japan is one of the world’s richest countries, and it has the third largest economy in the world. It also has many famous cities, and a large population. In Tokyo alone, the population is 37,340,000, while Canada’s total population is only 38.44 million! No wonder Tokyo has a water supply shortage! In this city, the water supply shortage is caused by the population density, which is squeezed into just 17% percent of Tokyo.
Commonly, in cities, you see mostly houses, malls and buildings because of large population. There is little visible greenery ; trees. Because there's no trees, water cannot reach into the ground, which means less water for the urban areas.
The United States has listed water scarcity, and other consequences of overpopulation and climate change, as a threat to national security, realizing that water scarcity can cause social and political issues. To help stop countries from engaging in conflict over water resources, government leaders need to recognize how water is a finite resource, and the consequences that can happen when a finite resource is abused. There has to be agreements and contracts between nations who are in water stressed regions and who share the same water source that outline distribution amounts according to population size and or agricultural needs.
As the global population is expected to keep growing, the negative impact on earth's limited resources, especially water, will become increasingly clear as the world will start to face extreme shortages of water, leading to instability in food production, industry, social order, and political and military control. To limit conflict over limited water resources, there needs to be compromise and cooperation between all countries, not just the nations that are water stressed, to provide water management techniques, newer and more efficient technology to conserve as much water as possible, and strict security and enforcement of all regulations to prevent groups and individuals using water to gain power.
⅔ of the global population live under the condition of water scarcity at least one month of the year.
The estimated population in the next 100 years is thought to be 10.8 billion.
By 2050, 1 in 5 developing countries will face water shortages Between 2050 and 2100, there is an 85% chance of a drought United States lasting more than 35 years!
Based on my research studies, I found out that my hypothesis is correct because the population growth leads to higher demand for water. Also, the areas with most water scarcity are those with less water resources and a high/dense population. Moreover, climate change, pollution, deforestation and over usage are obviously the results of population growth. When population increases, more trees and forests have to be cut down to clear lands to make more houses, roads, malls, other constructions, for agriculture land, & raise livestock. Less trees means less groundwater. And also less tree means more carbon dioxide in the atmosphere, which leads to global warming and climate change which leads to melting of polar ice caps and glaciers.This will reduce freshwater, resulting water scarcity. And also, speedy drying up of water bodies. Population growth causes more waste & packaged things to be made. Too much waste will end up thrown in rivers & there will be more landfills, which means there will be leachate, which can pollute the water. Finally, over usage of water is caused by population growth because growing population needs more water, & not everyone uses the same amount of water. In the end, there will be water scarcity.
- Think globally, act locally: Individual efforts to conserve water actually have a bigger impact than you think.
- Turn off the water when brushing, washing the car, doing the dishes & cleaning vegetables
- Take short showers or baths.
- Buy a rain barrel to store water for plants, & water plants in the evening so the water does not get evaporated.
- Fix leaks & drips
- Plant perennial & drought resistant plants.
- Use your automatic dishwasher & washing machine only when fully loaded
- Use technology to reduce water waste, for example: sensor taps, sensor showers,
- Change your lifestyle: Encourage people to eat plant-based food or seafood.
- Encourage recycle, reuse, reduce, rethink, & renew.
- Educate people:
- It will reduce childhood marriage, early pregnancy, so does population growth.
- About water conservation, reforestation, & global warming
- Encourage celebrating Earth Day (April 22nd), World Environment day (June 5th), World Water Day (March 22), International Day of Forests (March 21) to raise awareness among people.
- Governments can make laws to protect natural resources, including water reserves.
- Countries need to find solutions too.
- Saudi Arabia is converting saltwater to freshwater by desalination, even though it is expensive.
- Singapore is purifying wastewater that comes from washing dishes, flushing toilets, & take baths. Even though some other countries are doing this, Singapore obtains one- third of its water this way.
- Capetown is South Africa was about to become the world's first zero water county in 2018. The residents were restricted to only 13 gallons of water a day for all their needs. Fortunately, the Western Cape has received above-average winter rains, which has helped alleviate the city's drought stress and replenished the dams Water conservation is complicated, still, we all need to find ways to preserve this valuable resource for us and our future generations.
Links & Resources
https://gpm.nasa.gov/education/water-cycle#:~:text=The%20water%20 cycle%20 describes%20how,to%20the%20 surface%20as%20 precipitation.&text=The%20 cycling%20of%20water%20 in,the%20weather%20 patterns%20on%20Earth.
Special thanks for all the websites I used, and also my mom & dad for some info, & the teachers who encouraged us to do the science fair! :)