Polluted Water: Identifying The Visual Signs Of Contamination

Water pollution is a serious public health issue that affects our rivers, reservoirs, lakes, and seas. It can result from various factors, including industrial discharges, agricultural runoff, sewage overflows, and chemical spills. While some signs of water pollution are subtle, others are more obvious. This paragraph aims to provide an overview of the topic by discussing the different forms of water pollution and the ways in which concerned citizens can identify and address this pressing issue.

Unusual colour, taste, or smell

Water pollution is a serious public health issue that can cause illnesses in humans and distress or death in wildlife. Polluted water can exhibit unusual colours, tastes, or smells, signalling the presence of harmful contaminants. Here are some indicators to watch out for:

Unusual Colour

The presence of an unusual colour in water is often a tell-tale sign of pollution. For instance, high manganese levels can cause water to appear purple or black. An abundance of algae, often due to sewage or agricultural pollution, can make the water look bright green or blue-green, sometimes with a dirty and crusty surface. Waterways affected by sewage overflow or chemical spills may also exhibit discolouration.

Unusual Taste

Pay attention to the taste of your drinking water, as unusual flavours can indicate contamination. A metallic, oily, or fishy taste may suggest the presence of toxins like lead, which is unsafe for consumption and can lead to health issues.

Unusual Smell

Strong, unusual, or unpleasant odours in water often indicate contamination. Be cautious if you detect smells resembling sewage, chemicals, sulphur, paint thinner, or a metallic scent. A chlorine smell is usually added to treat bacteria and harmful microorganisms, but the presence of other unusual smells warrants concern. Sewage fungus, a type of slimy, bad-smelling, murky brown bacteria, is another indicator of nutrient-polluted water.

Remember, if you suspect water pollution in your local waterways or notice any unusual colours, tastes, or smells, it is crucial to report your observations to the relevant environmental authorities or local water management agencies. They are equipped to investigate and address pollution to protect our precious water sources.

Abundance of algae

Algae are microscopic organisms that can be found in all types of water, including salt water, fresh water, and brackish water. An abundance of algae, also known as an algal bloom, can be identified by different coloured foams or scum floating on the surface of the water. These foams can be creamy brown, green, blue-green, red, or brown in colour, depending on the type of algae. For example, a non-toxic algae called Phaeocystis forms large blooms that create a creamy brown foam as it breaks down, while the algae Noctiluca turns the sea red, orange, or brown. Blue-green algae, or cyanobacteria, can be found in calm, nutrient-rich waters such as ponds or lakes.

Algal blooms can occur naturally, but they are becoming more common due to human activities, particularly agricultural and industrial runoff that introduces excess nutrients such as nitrogen and phosphorus into waterways. This phenomenon, known as nutrient pollution, acts as a fertiliser and promotes the growth of algae and bacteria. Most excess nutrients enter waterways through agricultural runoff, such as animal manure and chemical fertilisers, as well as leaked waste from animal feedlots, stormwater runoff, and discharges from wastewater treatment facilities.

The presence of an abundance of algae can have negative consequences for the environment and human health. As the algae decompose, they deplete the oxygen levels in the water, creating "dead zones" where fish and other aquatic life cannot survive. Additionally, some types of algae produce toxins that can be harmful to humans, animals, and other parts of the ecosystem. These toxins can cause various health issues, including gastrointestinal illness, liver damage, vomiting, diarrhoea, confusion, seizures, memory loss, and even death in severe cases.

To address the issue of algal blooms, researchers are working on ways to predict and prevent their occurrence. Regulations have also been implemented in some countries to restrict agricultural and industrial operations from releasing pollutants into lakes, streams, and rivers, and treatment plants help ensure that drinking water is safe for consumption.

Sewage fungus

The presence of sewage fungus indicates a high level of organic pollution in the water. It is characterized by a slimy, murky brown appearance and a distinct foul odour. In 2022, there were 389,165 sewage spills reported in the UK, contributing to the proliferation of sewage fungus. Imaging techniques and machine learning can be used to identify sewage particles and sewage fungus in water samples, aiding in early detection and pollution control.

The bacterial taxa commonly associated with sewage fungus include Sphaerotilus natans, Zoogloea spp., Beggiatoa spp., Rhodoferax spp., and Thiothrix spp. Fungi, algae, archaea, and protozoa are also integral components of the biofilm. Sewage fungus has been found to accumulate heavy metals and other toxic substances, causing ecological impacts throughout the food web.

Dead animals

Water pollution has a devastating impact on animals, especially aquatic life. The presence of dead animals in water bodies is a stark reminder of the harmful consequences of water pollution.

Water pollution also reduces oxygen levels, creating "dead zones" where water is devoid of life. This occurs when pollutants stimulate excessive plant and algae growth, which, upon decomposition, consume large amounts of oxygen, leaving aquatic animals, such as crustaceans and shellfish, to suffocate.

Plastic pollution is another significant concern, with at least 100,000 marine animals dying each year due to ingesting plastic or getting entangled in it. Plastic waste attracts contaminants and algae, making it more appealing to unsuspecting creatures. As plastics break down into micro and nano-particles, they proliferate through the food web, eventually reaching humans, as evidenced by the presence of microplastics in our bloodstreams.

The impact of water pollution on animals is not limited to aquatic ecosystems. Birds, bears, big cats, and wolves that rely on fish as a food source are also affected, either facing dwindling food supplies or consuming contaminated prey.

While the situation is dire, there are efforts to counteract the damage. Initiatives like the Ocean Cleanup project are using modern technology to remove plastics from the oceans, and schools are incorporating education about water pollution to raise awareness among the younger generation.

Foam

One source of foam pollution is firefighting foam, which has been found to contaminate water systems near military installations. This foam is laden with PFAS (per- and polyfluoroalkyl substances), which have been identified as a leading source of contamination in drinking and groundwater systems across all 50 states in the US. The environmental and health risks of PFAS have led to pressure on the Pentagon to limit PFAS pollution and to the EPA mandating the first-ever national safety limits for certain types of PFAS in drinking water.

In response to these concerns, efforts are being made to transition to PFAS-free foams for firefighting and other applications. For example, the US Air Force is adopting a new fluorine-free foam, or F3, that does not contain PFAS chemicals for use in fuel fire situations. This new foam has undergone rigorous testing and is considered safe for the environment and human health.

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