What Are The Biggest Sources of Water Pollution?

Water pollutants can come in many different forms and can have dramatic impacts on fragile ecosystems and aquatic life.

There are a huge number of different sources of pollutants and each can have very different levels of harmfulness and environmental impact. In order to explain this further this article explains why water pollution is such an issue, as well as some of its main causes.
Water Pollution on riverside

What classifies as water pollution and why is it an issue?

The UN declared 2005-2015 as the International Decade for Action ‘Water for Life’. Yet each day thousands of people still die as a result of contaminated water. This does not even take into account the millions of organisms that perish every year thank to polluted water sources.

Water pollution is a huge issue that is made more so by the fact that unfortunately, water is easily solvent. This means that most chemicals are capable of breaking down within it, causing contamination.

Water pollution is the environmental degradation of water bodies via contamination, usually as a result a lack of effort to remove harmful man-made chemicals before pollutants are discharged. Of all sources marine pollutions, 80% comes from the land.

There are two main classifications of water pollution; point and nonpoint. Point pollutants come from a single sources, such as a leak, whilst non-point contamination are the results of an accumulation of pollutants from various sources.

We also need to take into account the different types of water. When thinking of water, most will automatically consider the obvious surface waters; lakes, rivers and oceans. But Earth’s water doesn’t solely consist of liquid existing in these locations. There is also groundwater: water held underground in aquifers which feed into these surface waters. Therefore anything that contaminates the groundwater in the aquifers will also likely contaminate the surface water.

Surface water pollutants are often more obvious; the Deepwater Horizon oil spill of 2010 in the Gulf of Mexico, whilst an extreme example, shows how much more obvious superficial pollutants can be. Yet pollutants, however they enter the system, can be detrimental to life on the planet, thanks to our dependency on clean water.

According the 2010 report, ‘Sick Water’, more people die from contaminated water than from war.

Polluted Water

Whilst not all water pollution is organic, with some coming from trees, plants and other organic sources, the biggest offenders are man-made and do not seem to be decreasing. Global warming is also intensifying the problem. During heavy rain or floods, pathogens – disease causing bacteria – like Leptospira, hepatitis, norovirus and cryptosporidium become increasingly problematic. As the human population increases, so too does the pressure on the environment.

The most common non-organic pollutants

The most commonly recognised non-organic pollutants are:

  • Sewage
  • Nutrients
  • Waste water
  • Industrial waste
  • Chemical waste
  • Radioactive waste
  • Oil pollution
  • Plastics

80% of marine pollution comes from the land, meaning it occurs during run-off. Much of the marine pollution is nonpoint and therefore comes from multiple sources, making it difficult to find the specific root cause and therefore efficiently correct or control the issue.

Examining the main contributors can give us a good idea of exactly where much of the blame lies, but without preventative measures and constant water monitoring being established large-scale, the future is not hopeful.

Industrial waste and sewage

Industrial waste (chemical and radioactive) and sewage account for around half of the world’s pollution problems. In 2006, Environment Agency data attributed nearly a quarter of the serious water incidents in England and Wales to the water and sewage industry.

Many industries do not have a proper waste management system or consider their contribution to be insignificant. They frequently drain waste products off into fresh water supplies which are then carried into oceans.

Agricultural pollution is also a major problem, thanks to chemical run off from the treatment of fields and, frequently, animal waste from smaller properties is left to run into groundwater supplies. The spreading of manure, disposal of sheep dip and use and improper disposal of pesticides and fertilisers all severely affect water supplies.

Domestic water pollution

Sewage from domestic properties is usually chemically treated and then released into fresh water. This does not mean that it is not a pollutant; indeed the chemical treatment can in some cases worsen the issue. Despite treatment, sewage water can still contain harmful pathogens that drastically damage human health. The microorganisms that reside in the sewers and drainage systems of cities are then carried outwards into the water supply and can then cause significant damage.

To make matters worse, many of us pour domestic and commercial chemicals down the drain on a daily basis or dump them in landfill sites where they can seep into the water system, and become an issue. Sewage becomes even more problematic when lines are damaged and leakage occurs.

Fossil fuels

The use of fossils fuels has caused irreparable damage to the planet. Water ecosystems are no exception to this.

Oil spillages are one of the more publicised and recognised water pollutants, but the everyday use of fossil fuels is also having a consistently poor effect on the water system.

The toxic chemicals released into the atmosphere when they are burnt mix with water vapour to form acid rain. Global Warming caused by the production of carbon dioxide as a result of burning fossil fuels also has a hugely negative impact on the water ecosystems, explained further here.

Beach health advisory sign

How water monitoring can help

As not all water pollution is not immediately obvious, it is important to be able to test any and all water sources. Regular testing can prevent pollution causing severe health problems and disasters, before they cause irreparable damage. A real example of this is the case of Walkerton, Canada in 2000. An accumulation of pollution in the water supply led to an e-coli outbreak that killed seven and affected nearly 2,300. The contamination in the public water supply was not officially recognised early on and the situation was not effectively managed.

Water lab technician

Domestic and commercial testing kits are available to check water quality. In some cases, regular check is required by regulation, but it may also be undertaken for your own peace of mind. Aquaread offer a variety of kits to test the cleanliness and quality of water supplies and sources, so you can be confident that your water is not being contaminated. To find out more about our water quality products, see our product page.