Courses
Courses for Kids
Free study material
Offline Centres
More
Store Icon
Store

Causes of Water Pollution and Their Environmental Impact

share icon
share icon
banner

What Are the Major Causes of Water Pollution Definition Types and Sources

Water is a very important source which is required by all living beings on the planet. Over two-third of earth, the surface is covered by the water whereas less than one third is covered by land. But the pollution of water causes a lot of distress for the living beings on this planet.  Clean water is mandatory for life when water gets polluted it becomes unhealthy for everyone. Water Pollution has affected the lives of animals, plants, and even humans, as all of us are greatly dependent on it. Water Pollution is major contamination of water bodies like lakes, rivers, oceans, etc.  This is caused when the pollutants are directly or indirectly discharged into the water bodies.


Water is the most significant resource for survival on a planet. It's the essence of life on our planet – Earth. Nonetheless, if you ever see a stream or lake around your town, it'd be evident to you that we have a tendency to face an awfully major problem of pollution. 


The Importance of the Water and Water Cycle

As you already know, water is all over and everywhere around.  However, we have a set quantity of water on earth. It simply changes its states and goes through a cyclic order, referred to as the water Cycle. The water cycle is a natural action that's continuous in nature. it's the pattern within which the water from oceans, seas, lakes, etc gets gaseous and turns to vapor. Then it goes through the method of condensation, and at last, precipitation once it falls back to earth as rain or snow.


Water Pollution

Water Pollution is the contamination of water bodies (like oceans, seas, lakes, rivers, aquifers, and groundwater) sometimes caused thanks to human activities. pollution is any amendment, minor or major within the physical, chemical or biological properties of water that eventually ends up in a prejudiced consequence of any living organism. The beverage, referred to as Potable Water, is taken into account safe enough for human and animal consumption.


Sources of Pollution

Some of the factors of Water Pollution are caused by direct sources, like factories, waste management facilities, refineries, etc., that directly releases waste and dangerous by-products into the closest water supply while not treating them. Indirect sources embrace pollutants that infuse within the water bodies via groundwater or soil or via the atmosphere through acidic rain.


The Consequences of Water Pollution

  • Diseases: In humans, drinking or overwhelming impure water in any manner has several unfortunate effects on our health. It causes typhoid fever, cholera, liver disease and numerous alternative diseases.

  • Eradication of Forests: The ecosystem is extraordinarily dynamic and responds to even little changes within the atmosphere. Increasing pollution will cause a whole planet to collapse if left unattended.

  • Effects of the Organic Wastes: Turmoil in the food chain happens once the aquatic animals (fish, prawns, seahorse, etc) consume the toxins and pollutants within the water, and then humans consume them.


Prevention of Pollution

The best way to stop large-scale pollution is to undertake and scale back its harmful effects. There are various little changes we can create to safeguard ourselves from a future wherever water is scarce.

  • Conserve Water: preserving water ought to be our initial aim. Water wastage may be a major drawback globally and that we are solely currently awakening to the difficulty. 

  • Treatment of Sewage: Treating waste products before doing away with them in water bodies helps scale back pollution on an oversized scale. Agriculture or alternative industries will use this effluent by reducing its deadly contents.

  • Use of Environment-Friendly Products: By using soluble products that don't change to become pollutants, we will scale back the quantity of pollution caused.

Life is ultimately about decisions and then pollution. we have a tendency to not brook sewage-strewn beaches, contaminated rivers, and fish that are toxic to drink and eat. To avoid these eventualities, we will work along to keep the atmosphere clean therefore the water bodies, plants, animals, and other people who rely on it stay healthy. We will take individual or teamed action to assist scale back pollution.


As an example, by exploiting environmentally friendly detergents, not gushing oil down the drains, reducing the usage of pesticides, and so on, we will take action as countries and continents to pass laws against pollution. We will try to make pollution less of a problem—and make the planet a stronger place.


More about Water Pollution

Water Pollution occurs when chemicals, waste, or other particles cause the body of water to be harmful to everybody. Causes of Water Pollution can be differentiated into 2 categories are as follows.

  • Natural Causes 

  • Human Causes


Natural Causes 

  1. Volcanoes

With large eruptions, volcanoes tend to change the climate for years. Volcanic eruptions spew out not just lava and ash but also gasses. Indeed it’s these gasses trapped under molten under great pressure in the molten rock that give eruption its explosive power. For the climate, the key gas is Sulphur dioxide. Once this gets into the Stratosphere, Sulphur dioxide from the volcano mingles with water forming tiny sulfate particles. The effects of ashfall from the volcano on natural waters have thereby led to an increase in Turbidity, which is the ash suspended in the water. When there is a volcanic eruption its ashes travel a great distance and when in contact with the vegetables, surface water and soils and groundwater it will contaminate it with metals like cadmium, arsenic, and copper and non-metal contaminants like fluorine. These will eventually enter the food chain, the process which takes pleasure for this is called Bioaccumulation. The contamination level increases as these travel up the food chain that can poison the livestock and the humans. This bioaccumulation in later stages will lead to cancer and may even result in the skeleton damage. 


(Image will be Uploaded soon)


  1. Animal Waste

The animal waste that comes out from the dairy and the poultry farm adds to Water Pollution. We also observe feces and urine of birds and the mammals are found widely across the globe, these frequently contaminate the water that has been used for the various purposes by humans and even for the irrigation of the crops. The risk of such kind of contamination has a major impact on human health which is very poorly understood among all. Direct exposure of humans to this animal can lead to many health hazards. There are many treatments that have been implied currently to treat this animal waste in order to reduce the Water Pollution caused by it. Animal waste is also utilized as a source in many of the fertilizers. The disposal of a larger quantity of animal waste on the land, as it is washed by rainwater leads to a large quantity of water degradation. The effects of animals have been calculated by using plots for their experiments and also simulating rainfall, to see how these even contribute as the samples of runoff water is collected and analyzed. They have concluded that land utilization of animal waste for the purpose of fertilization contributes significantly to Water Pollution and the use of tilling 


(Image will be Uploaded soon)


  1. Algae

They are responsible for the production of all kinds of water bodies and are involved in Water Pollution in many ways. The introduction of the organic effluents by enrichment of algae nutrients in water will lead to significant growth in the algal species thereby affecting the quality of water and its use. The algae in Water Pollution can be toxic to humans, animals, and fish who are consuming polluted water. Algae play an important role in the food chain of aquatic life, hence the type and the number of algae if altered will affect the organisms in the food chain fish being included in it. Algae are known to cause the taste and odor in water, a large number of algae are associated with this which are of different types. The Blue-green algae and particularly Chrysophyta and Euglenophyta are the once that cause such issues in the water supply. There are some algae that produce aromatic odor which is observed in some vegetables and flowers. In addition to this algae also produces odor of that of fish and grass. Algae is said to be one of the best Bioindicators, that is used to identify the quality and effects of pollution in the ecosystem and how long such issues may persist. Algae are used as Bioindicators for the following reasons.

  • They have a wide range of spatial and temporal distribution

  • In several years we see many algal species

  • Their response is quicker caused due to environmental pollution

  • They are usually found in larger quantities as they diversified

  • They are easily spotted and sampling is simpler

  • The algal presence is correlated with some kind of pollution


(Image will be Uploaded soon)


  1. Floods

Water moving in a high momentum causes a lot of destruction which is carrying a lot of sediments and other materials called the flood which becomes a major cause for Water Pollution. The flood moves unevenly in the geographical regions, this movement is also responsible for soil erosion. There will be many particles flowing in the flooded water which inter mix itself with the river or the surface waters like rivers, ponds, lakes, and oceans. In the end, these flooded particles will get deposited on the surface waters causing the pollution of water. Floods in its destructive movements pick up plant fertilizers, bodies, and other kinds of debris. The end result causes all of these contaminants to get mixed-up in the surface water causing Water Pollution. Flood also causes a huge loss in both life and prosperity, as it causes destruction in the path it takes. There is also a lot of loss of drinking water as well as it comes in contact with the contaminated waste. This causes a huge impact on the health of living beings. The contaminant that flows along with the floodwater is in very high volume and it courses over many landscapes carrying all the waste in its path.


(Image will be Uploaded soon)


Human Causes

  1. Chemicals

Both the industry and agriculture work requires the use of different kinds of chemicals, which are later released into the water. Chemicals released by the smokestacks (Chimney) enter the atmosphere and then fall back to the earth as rain. This enters seas, rivers, and lakes thereby causing Water Pollution which is called Atmospheric Deposition. On utilizing the fertilizers in the fields by the farmers, the chemicals used by them are thereby gradually carried away by rain into the groundwater or surface water nearby which leads to the contamination of the water. Detergents and many chemicals used in the manufacturing units also pollute the surface and groundwater. Another kind of toxic pollution comes from heavy metals such as lead, which is commonly used in gasoline, cadmium, and mercury which is commonly used in batteries. Metals and solvents that come out from the industries pollute the lakes and the rivers. Exposure to these substances for aquatic life is very poisonous, it might lower their development rate, making them infertile and even result in the death of many species. There are many different kinds of chemicals that have been poured into the rivers, these chemicals exhibit different effects based on the location and the kind of chemical that has been disposed of. Polluted water is the cause for the spread of many diseases such as typhoid, cholera, encephalitis, poliomyelitis, hepatitis, skin infection, and gastrointestinal. It is being educated by the health departments to examine the water that we intake in order to maintain good health.


(Image will be Uploaded soon)


  1. Sewage

The term savage is used to describe water waste that contains feces, laundry waste, and urine. The disposal of sewage is a major issue that we have in many countries as they lack proper sanitary conditions. Disposal of untreated sewage water would result in contamination of the air and water around it. Sewage treatment is usually carried out in the water treatment plants thereby disposing the waste over to the sea. We can say that sewage is biodegradable and can be broken down by the environmental conditions. It is estimated that more than 850 billion gallons of this vile brew escape the sea. This foul slurry pollutes the water bodies that are nearby after it comes out of the broken pipes and manholes. Some of it is pumped out, treated and piped back to homes and businesses from there it travels to sewer systems and the cycle repeats itself. Sewage disposal affects people’s immediate environment and this leads to water-related illnesses such as Diarrhea that kills 760000 Childers below 5 years every year. Whenever we flush the toilets it also travels somewhere and even after this has been treated there will always be some waste particles that need to be taken care of to be disposed of. There are themes when the sewage water which is untreated ends up in the sea. The sewage that comes out of the home undergoes 2 stages of treatment. Primary treatment comprises sedimentation and dyeing of soils, which is further used as fertilizers. The secondary treatment consists of the aeration of the liquid which is remaining, this is done via a process of stirring, trickling over the fertilizers and spraying. The remaining organic matter is oxidized by aerobic bacteria.


(Image will be Uploaded soon)


  1. Nutrients

Suitable, treated and used in moderate quantities, sewage can be a fertilizer. Chemical fertilizers used by the farmers also add nutrients to the soil, which drain into rivers and seas thereby adding to the fertilizing effect of the sewage. Together fertilizer and sewage can cause a massive increase in the growth in algae or planktons. This overwhelms huge areas in the oceans, lakes, or rivers. This is known as a Harmful Algal Bloom. 


  1. Highway Runoff

A lot of toxic pollution also enters the wastewater from the highway runoff. Highways are typically covered with a cocktail of toxic chemical waste. This includes everything from spilled fuel, brake fluids, bits of worn tires, and exhaust emissions. When there is rain these chemicals get washed into drains and rivers.


High concentrations of metals are found in the soul close to 100 ft of the highway. The quality of water in highway runoff discharges could result in a significant increase in suspended sediment deposition. Sediment concentration which we see in the localized areas are much closer to the source.


(Image will be Uploaded soon)


  1. Radioactive Waste

The higher concentration of this can kill and in lower concentrations, it causes cancers and other illnesses. The biggest source of radioactive pollution can be seen in the places that factories where it reprocesses waste fuel from the nuclear power plant.


(Image will be Uploaded soon)


  1. Oil 

Huge black oil slicks represent a tiny fraction of all the pollution that is entering the oceans. Only 12% of the oil that enters the ocean comes from tanker accidents and over 70% of oil pollution at the sea comes from routine shipping and from the oil that people pour down the drains on the land.


(Image will be Uploaded soon)


  1. Plastic

This is the most common substance that washes away with the waves and this causes a major hazard to seabirds, fishes, and other marine creatures. This is observed as plastic fishing lines and other and other debris can strangle or choke fish. 


(Image will be Uploaded soon)

Want to read offline? download full PDF here
Download full PDF
Is this page helpful?
like-imagedislike-image

FAQs on Causes of Water Pollution and Their Environmental Impact

1. What are the main causes of water pollution?

The main causes of water pollution are the introduction of harmful physical, chemical, or biological substances into water bodies. These pollutants degrade water quality and harm aquatic life.

  • Industrial waste containing heavy metals and toxic chemicals
  • Sewage and wastewater from households and cities
  • Agricultural runoff with fertilizers and pesticides
  • Oil spills from ships and drilling activities
  • Plastic and solid waste dumped into rivers and oceans
These sources contaminate rivers, lakes, groundwater, and oceans, leading to serious environmental problems.

2. How does agricultural runoff cause water pollution?

Agricultural runoff causes water pollution by washing fertilizers, pesticides, and animal waste into nearby water bodies during rainfall. This process increases nutrient levels and introduces toxic chemicals.

  • Excess nitrates and phosphates cause nutrient enrichment
  • Pesticides contaminate aquatic ecosystems
  • Animal waste adds pathogens and organic matter
This often leads to eutrophication, oxygen depletion, and death of aquatic organisms.

3. What is eutrophication and how is it related to water pollution?

Eutrophication is the excessive growth of algae and aquatic plants due to increased nutrients in water, mainly from pollution. It is commonly caused by runoff containing nitrates and phosphates.

  • Rapid algal growth forms algal blooms
  • Algae block sunlight from reaching underwater plants
  • Decomposition of algae reduces dissolved oxygen
Low oxygen levels can cause fish kills and disrupt aquatic ecosystems.

4. How does industrial waste lead to water pollution?

Industrial waste leads to water pollution by releasing toxic chemicals, heavy metals, and untreated effluents into water bodies. These substances can be highly harmful to living organisms.

  • Heavy metals like mercury and lead accumulate in aquatic organisms
  • Chemicals alter the pH and temperature of water
  • Toxic substances enter the food chain through bioaccumulation
This contamination affects both aquatic biodiversity and human health.

5. What role does sewage play in causing water pollution?

Sewage causes water pollution by introducing organic waste, pathogens, and nutrients into water bodies. Untreated or poorly treated sewage is a major source of contamination.

  • Adds disease-causing bacteria and viruses
  • Increases biological oxygen demand (BOD)
  • Raises nutrient levels, promoting algal growth
High BOD reduces dissolved oxygen, harming fish and other aquatic life.

6. How do oil spills contribute to water pollution?

Oil spills contribute to water pollution by forming a thin layer of oil on the water surface that blocks oxygen exchange and harms marine organisms. They usually occur during drilling or transportation of petroleum.

  • Coat feathers and fur of birds and marine mammals
  • Reduce oxygen diffusion into water
  • Release toxic hydrocarbons
This disrupts marine ecosystems and can cause long-term environmental damage.

7. What is the effect of plastic waste on water pollution?

Plastic waste causes water pollution by accumulating in water bodies and breaking down into microplastics that harm aquatic organisms. Plastics are non-biodegradable and persist for long periods.

  • Marine animals ingest plastic particles
  • Plastics release toxic additives
  • Block waterways and disrupt habitats
Microplastics can enter the food chain and affect both wildlife and humans.

8. Can water pollution affect human health?

Yes, water pollution can directly affect human health by contaminating drinking water with pathogens and toxic chemicals. Polluted water can cause serious diseases.

  • Waterborne diseases like cholera and typhoid
  • Heavy metal poisoning from contaminated water
  • Long-term health issues due to chemical exposure
Safe water treatment and sanitation are essential to prevent these health risks.

9. What is the difference between point source and nonpoint source water pollution?

The difference between point source and nonpoint source water pollution is that point source pollution comes from a single identifiable source, while nonpoint source pollution comes from diffuse, widespread sources.

  • Point source: Factory discharge pipe, sewage outlet
  • Nonpoint source: Agricultural runoff, urban stormwater
Point sources are easier to monitor, whereas nonpoint sources are harder to control and manage.

10. How does water pollution affect aquatic ecosystems?

Water pollution affects aquatic ecosystems by altering water chemistry, oxygen levels, and biodiversity. Pollutants disrupt the balance of aquatic life.

  • Reduce dissolved oxygen, causing fish deaths
  • Introduce toxic substances into the food web
  • Destroy habitats such as coral reefs and wetlands
These changes can lead to loss of species, reduced productivity, and ecosystem imbalance.