Water Pollution

Water contamination, release of substances in groundwater or in lakes, streams, rivers, estuaries and oceans to the point where substances interfere with beneficial water use or natural ecosystem functioning. In addition to the release of substances, such as chemicals or microorganisms, water contamination may also include the release of energy, in the form of radioactivity or heat, into bodies of water.

Water bodies can become contaminated with a wide variety of substances, including pathogenic microorganisms, putrescible organic waste, plant nutrients, toxic chemicals, sediments, heat, oil (oil) and radioactive substances. Several types of water pollutants are discussed below. (For a discussion on wastewater management and other forms of waste produced by human activities, see Waste Disposal).

Causes of water pollution

Domestic wastewater

Domestic wastewater is the main source of pathogens (disease-causing microorganisms) and putrescible organic substances. Because pathogens are excreted in faeces, all wastewater in cities and towns is likely to contain pathogens of some kind, which could pose a direct threat to public health. Putrescible organic matter presents a different type of threat to water quality. As bacteria and other microorganisms naturally break down organics in wastewater, the dissolved oxygen content of the water runs out. This jeopardizes the quality of lakes and streams, where high oxygen levels are required for fish and other aquatic organisms to survive. Wastewater treatment processes reduce levels of pathogens and organic compounds in wastewater, but do not eliminate them completely.

Agriculture

The agricultural industry is one of the largest consumers of freshwater. In the United States, it is responsible for about 80% of the country's water consumption. Agriculture is also the main source of pollution in U.S. rivers and streams.

One of the ways agriculture pollutes water is through rainwater. When it rains, contaminants, such as fertilizers, animal waste and pesticides, are washed from farms to watercourses, contaminating water.

Agricultural pollutants often contain high amounts of phosphorus and nitrogen, which encourage the growth of algae blooms. These blooms produce toxins that kill fish, seabirds and marine mammals, as well as harm humans.

In addition, when these algae blooms die, bacteria produced as algae break down consume oxygen in the water. This lack of oxygen causes "dead zones" in the water where fish cannot live.

The United Nations Education, Science and Culture Organization (UNESCO) estimates that there are approximately 245,000 square kilometres of dead zones worldwide.

Plastics and garbage

Approximately 1.4 billion tons of waste is produced each year. Of these annual wastes, 10% are plastics. Due to the widespread use of plastics, experts estimate that between 4.8 and 12.7 million tons of waste enter the ocean each year.

Plastic and trash cans enter the water in many ways:

1.debris falling from ships

2.garbage falling into the ocean from landfills

3.garbage dragged into the sea through the rivers of people discarding used items, such as food packages

4.people throwing garbage at the beach

5.Once in water, plastic and garbage can harm marine life and human health. Fish can eat garbage, mistake it for food and end up dying.

As the plastic breaks slowly, microplastics form. These are small plastic fragments less than 5 millimeters in size. Fish can consume these microplastics, which can then be consumed by humans.

The UN claims that plastic waste in the ocean kills more than one million seabirds each year. Plastic waste is also responsible for the deaths of more than 100,000 marine mammals per year.

What can you do to prevent water contamination?

It's easy to ask the oil company with a leaky tanker truck, but we're all responsible to some extent for the current water pollution problem. Fortunately, there are some simple ways to prevent water contamination or at least limit its contribution:

1.Reduce your plastic intake and reuse or recycle plastic when you can.

2.Properly dispose of chemical cleaners, oils and non-biodegradable items to prevent them from ending up in the drain.

3.Keep your car so you don't lose oil, antifreeze or coolant.

4.If you have a garden, consider gardening that reduces runoff and avoids applying pesticides and herbicides.

5.If you have a puppy, be sure to pick up its poop.