A Complete Guide to Water Pollution - Types, Causes and Effects

Variously known as aqua pura, Adam’s ale and the staff of life, water is the substance upon which all lifeforms on the planet depend for their survival. But despite the fact that over 70% of the Earth’s surface is covered by water, the rapid growth of the global population has placed an ever-greater strain on our supplies.

What’s more, our propensity for industrial activity – and our proclivity to not clean up after ourselves adequately – has contaminated reserves and depleted them even further. Indeed, water pollution is one of the biggest challenges facing the human race today. For those interested in expanding their knowledge on the subject, the following article will provide an introduction into all aspects of water pollution, including different types of contamination, the activities principally responsible for causing it and the tangible effects on human, plant, animal and environmental health.

What are the different types of water pollution?

Water pollution refers to the contamination of our rivers, lakes, reservoirs, streams, oceans and seas by foreign agents which have a negative impact upon its quality. However, this phenomenon can take many different forms depending on the body of water in question and the type of contaminant involved. Here’s a look at some of the major types of water pollution afflicting the world today:

• Groundwater pollution. This refers to the vast stores of H2O located in underground reservoirs and streams. When heavy metals, chemicals and other contaminants are allowed to leach into soil, they can eventually pollute groundwater.
• Surface water pollution. This is perhaps the most common form of water pollution and occurs via point source pollution (when the contaminants emanate from a fixed location, such as an industrial effluent or an oil tanker spillage) and non-point source pollution (when the contaminants are released from a variety of locations, such as from agricultural run-off, flooding or precipitation).
• Chemical pollution. This can take place in either of the above scenarios, but involves a specific contaminant: chemicals. These substances are commonly used in a wide variety of human activities on a daily basis, meaning that it’s inevitable some chemicals will end up being washed into our water sources.
• Nutrient pollution. Certain chemicals contain elements such as ammonia, nitrogen and phosphate. When allowed to infiltrate aquatic ecosystems, these elements can cause a nutrient imbalance in the water, promoting the growth of some species over others.
• Microbiological pollution. This type of pollution can often occur naturally and may not necessarily have undesirable outcomes. However, population density and industrial activity contribute to greater levels of microbes (such as bacteria, protozoa and viruses) in the water, many of which can transmit life-threatening diseases.
• Suspended matter pollution. If a particle is too big or too constant to dissolve in water, it is known as suspended matter pollution. These contaminants normally accumulate on the surface of the water in a thick scum, or else sink to its floor in a sludge-like substance.

What are the main causes of water pollution?

As you may have noted, the vast majority of the types of pollution listed above are entirely caused by (or at least exacerbated by) human activity. Of course, natural causes of water pollution do exist, such as volcanic ash or debris produced by forest fires. Nonetheless, mankind has made the issue significantly worse, with the following causes of water pollution among the most important:

• Untreated wastewater. By using sophisticated monitoring methods, the UN reports a staggering 80% of the world’s wastewater is released back into the environment without being treated. That makes it undoubtedly the biggest cause of water pollution, with the plants, animals and humans living in the vicinity exposed to the potential pathogens harboured in unclean drinking water supplies.
• Agricultural run-off. Chemical-based products such as fertilisers, herbicides and pesticides have become instrumental in boosting crop yields and ensuring there is enough to feed the global population. However, the nutrients contained in these products can be washed away into rivers, lakes and streams during and after periods of heavy rainfall.
• Oil spillages. Given that the world relies on fossil fuels for much of its energy needs and has done for centuries, it’s perhaps unsurprising that there have been several high-profile examples of water pollution as a result of oil spillages. The Deepwater Horizon explosion of 2010 was a particularly violent incident, in which hundreds of thousands of animals lost their lives.
• Dumping. Although human beings have achieved remarkable progress in the fields of science and technology over recent decades, that progress has not come without its price. Unfortunately, many people do not prioritise the environment when disposing of their waste and simply throw things out, after which they can be swept into our water sources.

What are the effects of water pollution on humans?

When water sources become contaminated, that makes them unfit for consumption by humans, exacerbating the issue of water scarcity. Meanwhile, the fact that around 70% of our freshwater reserves are used to cultivate crops means that food production is also compromised by poor water quality, as well.

If humans have no recourse but to drink polluted water, they will expose themselves to a dangerous cocktail of toxins. Toxins which carry diseases are called pathogens and, sadly, these are found in abundance in contaminated water sources all around the globe. When human populations are exposed to them and ingest the pathogens, they can contract a wide variety of diseases. These can include:

• Bacterial diseases, such as cholera, diarrhoea, salmonellosis and shigellosis, which can affect the digestive and intestinal tracts. Although most cases feature abdominal pains, fever, nausea and vomiting as their most common symptoms, they can sometimes end in death in the most extreme scenarios.
• Viral diseases, such as encephalitis, gastroenteritis, hepatitis and polio. These also induce nausea, fever and loss of appetite in mild cases, but can prompt the onset of paralysis, coma or even death if left untreated.
• Parasitic diseases, such as cryptosporidiosis, galloping amoeba, giardiasis and schistosomiasis. Spread by small parasites which breed and live in contaminated water, these diseases target the abdominal area and can result in severe discomfort and damage to internal organs.

A less publicised side effect of water pollution on humans is the economic impact that it entails. Millions of pounds are devoted towards cleaning up contaminated water sources after accidents and spillages, while the public health cost of treating those who have contracted the above conditions is also significant.

What are the effects of water pollution on the environment?

It’s not just the human race which suffers when water sources become contaminated, either. In fact, the greater ramifications are likely to be experienced by the natural flora and fauna in the vicinity of the pollution. Here are some of the ways in which water pollution can negatively impact the environment it contaminates:

• Eutrophication. An excess of nutrients in an aquatic ecosystem causes eutrophication, during which algae and phytoplankton are given a significant growth boost. This causes them to consume more than their fair share of oxygen and block out sunlight from reaching other organisms below, thus damaging overall biodiversity.
• Bioaccumulation. The presence of contaminants such as chemicals and heavy metals may start out as negligible in a sizable body of water. However, when they are absorbed or consumed by aquatic organisms, they can persist in their bodies for a long time. When those organisms are eaten by larger predators, the contaminants accumulate to alarming concentrations over time.
• Plastic pollution. Did you know that as many as 12 million tonnes of plastic enter our seas and oceans each year? Or that there are currently over 5.25 trillion pieces of plastic waste floating in our waterways? These plastic items can entangle or suffocate marine species, or else become ingested by them and harm their internal organs.
• Acidification. Carbon is often thought of as an atmospheric pollution, but scientists believe that up to 25% of carbon emissions are actually absorbed into the sea. This then causes the ambient temperature and the acidic content of the water to rise, disrupting the natural patterns of plant and animal life and contributing to serious issues such as coral bleaching.
• Loss of entire species. If pollution is allowed to reach such a catastrophic state as to threaten the life of whole populations of aquatic organisms, it could easily wipe out entire species. According to the World Economic Forum, we’ve lost some 60% of the planet’s wildlife species in less than half a century – and water pollution has undoubtedly played its part in that undesirable outcome.

What can we do to reduce water pollution?

Although the situation is a serious one, it’s thankfully not beyond salvation. It will take a concerted effort from governments, businesses and individuals to reduce their negative impact on water quality so as to safeguard this most precious resource and mitigate our damaging effect on the planet.

In terms of governmental apparatus, stricter requirements on wastewater treatment must be instituted across the globe. Standards are certainly higher in more developed parts of the world, though more work must still be done to ensure that they are being adhered to. Meanwhile, those living in impoverished regions are most affected by water pollution and significant investment, alongside strong political will and excellent organisational skills, must be employed to introduce adequate drinking water and sanitation facilities for those who need them most.

At the business level, companies must begin to take responsibility for the pollution they generate. This means ensuring they follow all best-practice protocols and meet legal obligations, as well as implementing forward-thinking practices aimed at curbing water contamination. This could take a variety of forms depending on the industry in question, but moving away from fossil fuels in the energy industry, following green farming methods in the agricultural sector and introducing a corporate and social responsibility drive in all companies and corporations are just some of the ways the world of commerce can reduce water pollution.

Finally, each and every one of us has a role to play in ensuring we don’t make the issue any worse. Some concrete steps we can take include conserving water as much as possible, reducing our consumption of plastics, eating organic foods and reusing, repairing and recycling as much as we possibly can.

For those interested in learning more about the topic of water pollution, the upcoming Water, Wastewater and Environmental Monitoring (WWEM) exhibition promises to be a great source of information. Scheduled to take place in Telford in the UK on the 12^th and 13^th October 2022, the exhibition will cover the subject from all angles.