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11 Causes of Water Pollution

Muhammad Rafiq is a freelance writer, blogger, and translator with a master's degree in English literature from the University of Malakand.


What is Water Pollution?

Water pollution refers to the presence of harmful or undesirable substances in water, such as soil fertilizers, pesticides, aquatic organisms, pharmaceuticals, herbicides, industrial chemicals, automotive fluids and oil, heavy metals, or waste from various human activities.

Water pollution can affect any natural body of water on earth, including oceans, rivers, and lakes. While the chemical makeup of each water source differs and therefore causes unique problems, the most common sources of water pollution are trash, overfishing, and farming runoff.

In order to understand its harmful effects, it’s important to first know what it is, how it happens, and which types of pollutants exist in our water today. This article details 11 of the most common causes of water pollution as well as their impact on our environment and human health.

11 Causes of Water Pollution

  1. Industrial Waste
  2. Land Based Pollution
  3. Plastic Waste
  4. Acid Rain
  5. Industrial Fertilizers
  6. Sewage
  7. Agriculture Runoff
  8. Marine Dumping
  9. Oil Leaks and Spills
  10. Nuclear Waste
  11. Marine Traffic

1. Industrial Waste

Industrial waste can come from a variety of sources, including factories, power plants, and mining operations. This type of pollution can have a devastating effect on the environment and human health.

It contains a wide range of harmful substances, including heavy metals, chemicals, and toxic wastes. When this waste gets into our waterways, it can contaminate the water supply and make it unsafe to drink. It can also harm fish and other aquatic life.

Water pollution from industrial waste is a serious problem that needs to be addressed. There are a number of ways to reduce the amount of waste that is produced, and to ensure that it is properly disposed of.

One way to reduce industrial water contamination is to find ways to reduce the amount of waste that is produced. This can be done through a number of methods, such as improving production processes so that less waste is produced, or by recycling or reusing materials whenever possible.

Another way is to ensure that it is properly disposed of. This means that waste should be properly treated before it is released into the environment, and that it should be disposed of in a way that will minimize the risk of contamination.


2. Land-Based Pollution

Land-based pollution is another leading cause of water pollution. Along with agricultural and industrial runoff, it is a major contributor to the decline in water quality around the world.

Land-based pollution is a major problem facing our planet today. It comes from a variety of sources, including mining operations, construction sites, and even our own homes. When we don't properly dispose of our waste, it can end up in our waterways, where it can pollute the water and harm the plants and animals that live there.

This kind of pollution is a serious threat to the health of our planet, and it's important that we take steps to reduce it. There are a number of ways we can do this, including proper waste disposal, using less harmful materials, and increasing public awareness about the issue.


3. Plastic Waste

One of the most significant sources of water pollution today is plastic pollution. This is an enormous problem because plastic takes hundreds of years to decompose, so the plastic that was produced even just a few decades ago is still polluting the environment today.

Plastic pollution is a growing problem worldwide. Not only does it impact the environment, but it also contributes to water pollution. Here are five ways that plastic pollution can contaminate water:

  1. Plastic Litter: Plastic litter can end up in waterways, where it can pollute the water and cause harm to marine life. In addition to being unsightly, plastic litter can also block drains and sewers, which can lead to flooding.
  2. Leaching: Some plastics can leach chemicals into the water, which can be harmful to aquatic life and humans. The chemicals that leach from plastics can include additives such as plasticizers and flame retardants, as well as monomers that make up the plastic itself. These chemicals can have a variety of adverse effects on aquatic life, including endocrine disruption, reproductive toxicity, and cancer. In humans, these chemicals have been linked to a variety of health problems, including infertility, birth defects, and cancer.
  3. Microplastics: Microplastics are tiny pieces of plastic that can end up in the water. These can be ingested by aquatic life, and can also contaminate the water. Aquatic animals can mistake microplastics for food, and ingest them. This can cause them to feel full, even though they haven't eaten enough food. Ingesting microplastics can also cause blockages in the gut, and can lead to malnutrition. Microplastics can also absorb toxins from the water, which can then be ingested by the animal. This can lead to serious health problems, and in some cases, death.
  4. Stormwater Runoff: Plastic pollution can be carried by stormwater runoff into waterways. This is a serious problem because plastic pollution can clog drains and cause flooding. In addition, plastic pollution can pollute water sources and harm wildlife.
  5. Sewage: Plastic pollution can end up in sewage systems and eventually pollute waterways. This can have serious consequences for public health and the environment. Improperly managed sewage can contaminate water supplies, leading to waterborne diseases. It can also pollute rivers, lakes, and oceans, harming marine life and potentially affecting the food chain.

4. Acid Rain

Acid rain is another leading cause of water pollution. It erodes lakes, streams, and drinking water supplies, and it's harmful enough to kill aquatic life. Acid rain accumulates in the atmosphere when sulfur oxides, nitrogen oxides, and volatile organic compounds are released into the air.

When it rains, these chemicals become acid rain, which damages lakes and streams. Acid rain is a man-made problem. It's the result of industrial pollution from power plants, factories, and vehicle exhaust.

Acid rain is harmful to ecosystems because it lowers the pH (acidity) of lakes and streams. Acidic water reduces the chemical processes that are essential for the functioning of aquatic life. Acid rain also damages buildings and houses by growing and setting in on roofs made of cement or asphalt. The acid rain also erodes soil and causes damage to buildings and trees.

Acid rain also harms human health. Acidic rain can cause respiratory problems such as asthma, and breathing problems for people sensitive to environmental pollutants. Acid rain can also make people's eyes itch and hurt. Acid rain can also damage buildings and destroy artwork.

Fortunately, there are steps that we can take to reduce the amount of acid rain that falls. For example, we can work to reduce the amount of sulfur dioxide and nitrogen oxide in the air. This can be done by using less coal and oil, and by using cleaner burning fuels.

Another way to reduce acid rain is to plant trees and vegetation. This helps to absorb some of the pollutants in the air before they have a chance to turn into acid rain.


5. Industrial Fertilizers

Industrial fertilizers are the main sources of water pollution. Industrial fertilizers are produced from fossil fuels, such as coal, oil, or natural gas. Many farmers use industrial fertilizers to grow crops. Industrial fertilizers are concentrated mixtures of nitrogen, phosphorus, and potassium, but they often contain other chemical components as well.

The nitrogen in fertilizers comes from nitrogen-rich compounds called nitrates, which can leach into water supplies when fertilizer spills or leaks. These nitrates, once in the water, can cause problems for aquatic animals. .

The nitrogen in fertilizers can also get washed off fields. When it gets into bodies of water, it can cause algae to grow. Algae blooms suffocate fish and other aquatic animals. They force the animals to breathe through their gills, leading to oxygen starvation. When the algae dies, it releases toxic chemicals, which can kill other animals in the body of water.

Industrial fertilizers can also pollute the soil. When it rains, the nitrogen in the fertilizer washes into streams. The chemical can leach into groundwater, affecting groundwater quality.


6. Sewage

Sewage causes a variety of harmful consequences. It contains toxins and harmful bacteria, and when dumped into the environment, causes harm to humans and ecosystems.

There's a lot of sewage being pumped into rivers, lakes, and the ocean every day. Millions of gallons of sewage is added daily by humans, and even more by farm animals. With so many people, it’s easy to see how so much sewage ends up in bodies of water. But there’s no excuse for dumping sewage into freshwater resources.

Sewage can cause a variety of problems. It breeds bacteria—like Legionella and E.coli—which most commonly cause diarrhea, respiratory infections, and bloodstream infections. Other toxic substances like heavy metals, detergents, and mercury are flushed out while cleaning toilets and dishes. These can all lead to serious health problems if people are exposed to contaminated water.

It is, therefore, important to ensure that sewage is disposed of properly, in order to protect public health. Improperly disposed of sewage can contaminate surface and ground water, which can lead to the spread of disease. It can also lead to environmental pollution, as sewage can contain harmful chemicals and pollutants.


7. Agriculture Runoff

Almost 70 percent of the freshwater used in the world is used by agriculture. But agricultural runoff is a big cause of water pollution.

According to the U.S. Environmental Protection Agency, agriculture is the largest source of water pollution in the United States. And it’s not just the chemicals used in pesticides and fertilizers. Other pollutants in runoff include fertilizers and animal wastes, sediment, and heavy metals.

Runoff from agriculture can have a number of different impacts on the environment. Some of it becomes drinking water that we rely on, while others eventually find their way into the nation’s rivers and streams. On top of all that, agriculture’s runoff can also contribute to global warming.

Runoff from agriculture can happen when rainwater or irrigation water flows over the land and picks up things like pesticides, fertilizers, and other chemicals. This water can then end up in a number of different places.

Some of it flows into rivers and streams, which can eventually lead to contamination of the water supply. Other runoff may seep into the ground, where it can contaminate groundwater. This is a serious problem because it can lead to contamination of drinking water.


8. Marine Dumping

Marine dumping is a serious environmental problem, and can impact human health and ocean ecology. Even small amounts of garbage in the waters can cause extensive harm.

This happens when people toss unwanted items into the ocean. People dump anything from old fishing nets to gasoline, and even household garbage from bathrooms and kitchens. Marine dumping results not only from accidents, but also from careless littering and improper waste disposal.

While it's tempting to imagine marine dumping as accidental, the majority of marine trash such as trash and fishing gear is dumped intentionally. Marine dumping results from a lack of education on proper disposal, and from lack of publicly accessible facilities to recycle waste.

It is estimated that between 4.8 and 12.7 million tonnes of plastic waste are dumped into the world's oceans each year. This plastic pollution has devastating effects on marine life, with turtles, seals, and birds being particularly vulnerable. In addition to harming wildlife, plastic pollution also affects human health, as it can contaminate our food and water supplies.

The study published by Pew Charitable Trusts and SYSTEMIQ, Ltd. estimates that the amount of plastic waste will triple in the ocean by 2040. This increase is due to a combination of factors, including population growth, economic development, and increased plastic production.

The study calls for a major overhaul of the global plastics industry, shifting it to a more sustainable, circular economy that reuses and recycles materials. The study's authors say that such a shift is necessary and cheap to reduce the enormous environmental impact of plastic pollution.


9. Oil Leaks and Spills

Spills of oil and other petroleum products can occur from improper storage, improper disposal, and leaks from pipelines or storage tanks. These spills can cause environmental damage to soil, air, and water sources, and can affect human health.

Oil spills can damage water quality in several ways. They can cause oil to stain the surface of the water, making it difficult for animals or people to spot fish or other animals. They can also kill fish and other aquatic animals, pollute the food supply for other aquatic animals, and block sunlight from reaching underwater plants.

This can interrupt the food chain, lower crop yields for aquatic animals, and stop other animals from eating the plants.

Once an oil slick is in the water, it can take weeks or months for it to degrade. If oil slicks occur near fishing spots or in coastal areas, they can cause long-term harm.

The Exxon Valdez oil spill rocked Alaskan waters in 1989. The spill badly affected 1000 miles of Alaska’s remote coastline, killing thousands of birds and fish, and harming the health of thousands of others. The Exxon Valdez oil spill is still the worst oil spill on record.

To prevent oil spills, people must follow good safety procedures. Some accidents are caused by carelessness or mistakes. To avoid these accidents, people must take care when handling oil and always follow safety procedures. By doing so, we can help prevent oil spills and keep our environment clean.


10. Nuclear Waste

The radioactive materials in nuclear waste can contaminate water supplies, making them unsafe for human consumption. In some cases, nuclear waste can also leach into groundwater, causing long-term contamination of aquifers.

Nuclear power plants generate electricity by making use of nuclear energy, which is a form of energy that comes from splitting atoms, using a process called nuclear fission. Nuclear waste is the byproduct of this process, which contains radioactive materials that are dangerous and harmful to humans and the environment.

Nuclear waste can cause water pollution in a number of ways. First, if the waste is not properly stored, it can leak into the ground and contaminate groundwater supplies. This can lead to serious health problems for those who rely on groundwater for drinking, cooking, and bathing. In addition, contaminated groundwater can also harm the environment.

Second, if nuclear waste is dumped into rivers or lakes, it can contaminate the water and make it unsafe to drink. This can cause serious health problems for people who rely on these water sources for their drinking water. In some cases, it can even lead to death.

Third, nuclear waste can also cause air pollution if it is released into the atmosphere. This is because nuclear waste can contain radioactive particles that can be released into the air. These particles can then be inhaled by people, which can lead to health problems.


11. Maritime Traffic

Water pollution from maritime traffic is a serious global problem. Ships burn huge quantities of fuel oil, which contains harmful pollutants such as sulfur and nitrogen. These pollutants are released into the air and eventually fall into the oceans, where they can have a devastating effect on marine life.

Maritime traffic is responsible for a significant portion of the world's water pollution. This is a problem that is only getting worse as maritime trade increases.

There are a number of factors that contribute to water pollution from maritime traffic. First, ships often use heavy fuel oils that contain high levels of sulfur. When these fuels are burned, they release sulfur dioxide into the air. This sulfur dioxide then falls into the ocean, where it can interact with other chemicals to form sulfuric acid. This acid can damage marine life and ecosystems.

Second, ships also release a variety of other pollutants into the air and water, including particulate matter, nitrogen oxides, and carbon dioxide. These pollutants can also have harmful effects on marine life, causing respiratory problems, acidification of the ocean, and other problems.

Shipping companies must take responsibility for their pollution and work to find cleaner, more sustainable ways to power their vessels. Otherwise, the oceans and all the creatures that call them home will continue to suffer.



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This content is accurate and true to the best of the author’s knowledge and is not meant to substitute for formal and individualized advice from a qualified professional.

© 2022 Muhammad Rafiq