Why Water Pollution is Bad For the Environment
Water pollution is when human activities add contaminants to the water supply. This negatively impacts the health of plants, animals and humans in several ways.
Pathogens like bacteria, viruses and parasites contaminate waterways. These toxins cause diseases like diarrhoea, cholera, giardia and typhoid fever.
Chemicals and pollutants from fertilisers, plastics, sewage and pesticides also pollute water. Even natural disasters such as floods can cause significant water pollution.
1. Depletion of Oxygen
One of the most common types of water pollution is oxygen depletion. This happens when biodegradable matter like sewage, paper, aluminum and even organic waste from animals is released into watercourses and drains. This type of pollution reduces the amount of dissolved oxygen in water, allowing bacteria to thrive. It also causes fish to suffocate, which has a negative effect on the ecosystem.
Other pollutants include toxins from industry, such as heavy metals. These contaminants can be washed from streets, roads and footpaths into rivers and waterways when it rains. They may cause the water to be murky, cloudy or change its colour and salt content. Thermal pollution, which is caused by power plants using water to cool their processes, can also be dangerous for aquatic life.
2. Depletion of Nutrients
Water pollution is the contamination of a stream, river, lake, ocean or any other stretch of water. It’s caused by human activities, though natural events like landslides and floods can also degrade water quality. It’s important to stop water pollution because it can be dangerous to us and the ecosystems that depend on it.
The main types of water pollutants are pathogens (disease-causing microorganisms) and putrescible organic matter. Pathogens enter the water through sewage, which is often discharged into rivers and lakes. Dispersible matter comes from household waste like fertilisers, oils, detergents and paints that are poured down drains or washed from streets and footpaths into our waterways.
Industrial pollutants like heavy metals are another big threat to our water. They can contaminate fish and other wildlife, which in turn can be eaten by people.
3. Depletion of Carbon Dioxide
Water pollution comes from many direct and indirect sources. For example, chemical dumping from agricultural and urban sources (fertilizers, pesticides, herbicides, paints and solvents) may run off into streams and rivers. This stimulates algae growth, depleting water of oxygen (eutrophication) and suffocating fish, birds, mammals and plants. Rising global temperatures caused by CO2 emissions also heat up water, reducing its oxygen content and harming ecosystems.
The water supply is also polluted by disease-causing pathogens such as faeces, sewage and poorly functioning on-site sanitation systems, and toxic chemicals from industrial sites. Thousands of people worldwide die every year from contaminated drinking water. This is due to the presence of diseases like diarrhoea, cholera and typhoid in contaminated water.
4. Depletion of Biodiversity
Biodiversity loss is one of the biggest challenges for humanity and threatens global food security, environmental stability and the development of new pharmaceutical drugs. Specialist species, those adapted to limited habitats or specific food resources, are most likely to suffer dramatic population declines and even extinction as their ecosystems change.
Non-point source pollution is the result of a multitude of human activities that cause contaminant levels to increase beyond safe limits in a water body. These include the discharge of sewage, untreated blackwater (due to open defecation), excessive fertilizer use, industrial solvents and pesticides, sediment runoff from construction and agriculture, erosion and the release of volatile organic compounds.
Moreover, solid waste pollution occurs when garbage is dumped in bodies of water. For example, plastic trash and other rubbish that washes into rivers, lakes or oceans takes weeks to hundreds of years to break down, and it can harm marine life.
5. Depletion of Water Supply
Water pollution occurs when pollutants from human activities enter lakes, rivers, oceans and aquifers. Water is a universal solvent, so it dissolves many substances, including chemical contaminants, organic matter and pathogenic microorganisms. This makes it very vulnerable to pollution. In some cases, these pollutants may cause water to become murky, cloudy or coloured, or they may make it unsuitable for its natural uses.
Pollution from sewage plants and factories is one of the main causes of water pollution, as well as littering and poor sanitation practices. In addition, deforestation lowers soil’s ability to retain and store water. The over-pumping of groundwater also causes it to become depleted. These are all important reasons why we need to prevent water pollution.