Water Pollution: Causes, Effects, And Prevention Strategies

Water is the most important resource on the planet, and yet water pollution is a serious problem. Water pollution is the contamination of water bodies such as oceans, seas, lakes, rivers, and groundwater, and it is usually caused by human activities. The contamination of these water bodies by toxic chemicals, industrial waste, agricultural runoff, and other pollutants can have detrimental consequences for all living organisms, including humans, who can contract diseases such as hepatitis through faecal matter in water sources. Water pollution prevention practices include low-impact development, improved chemical handling, erosion control, and the use of environmentally friendly products.

Water Pollution Characteristics

Oil spills and leaks

Oil spills from ships and tankers are a major source of water pollution. In response, the United Nations treaty known as the Convention for the Prevention of Pollution from Ships, or MARPOL, was introduced in 1983. This treaty requires tankers and ships to use oil-pollution prevention equipment, such as double hulls, reliable navigation equipment, and communication tools. The double hull requirement adds an extra protective barrier to ships, helping to minimise the damage caused by leaks. Individual tanks within ships are also limited in size to contain leaks to a single compartment. These regulations have led to a significant reduction in oil spills, with the most notable decrease occurring in the United States during the 1990s.

Runoff from industrial and domestic operations is another significant source of oil pollution. Oil spills from fuel depots, vehicle and lawnmower leaks, and the improper disposal of paint or oil can all end up in storm drains, eventually reaching water sources. Pavement runoff is a significant contributor, with a city of five million people discharging as much oil into waters through pavement runoff as a large oil tanker spill. Additionally, only about one-third of the used oil from DIY oil changes is collected and recycled, with the remaining two-thirds contaminating freshwater sources.

The impact of oil spills on the environment and marine life can be devastating. Oil spills can harm sea creatures, ruin beaches, and make seafood unsafe to eat. Cleanup efforts can be challenging, and even with advanced technology, it is impossible to remove 100% of the spilled oil. In some cases, the cleanup methods themselves can cause additional harm, as seen in the Exxon Valdez oil spill, where high-pressure, hot-water hoses used for cleanup caused more damage than the oil alone. To address this issue, the Oil Pollution Act of 1990 was established, holding those responsible for oil spills accountable for the cleanup and restoration costs.

Industrial waste

The increased demand for goods due to population growth has accelerated industrialization, leading to a surge in industrial waste production. This waste is released into water bodies, causing water pollution and posing significant environmental and health risks. The contaminants in industrial wastewater can be toxic, reactive, carcinogenic, or ignitable, and they give rise to waterborne pathogens that produce toxins detrimental to the ecosystem and human health.

One of the major concerns with industrial waste is the contamination of drinking water. A News21 analysis of EPA data revealed that the drinking water of over 244 million people in the United States is contaminated with pollutants linked to industrial activities, such as arsenic, lead, mercury, and chromium. These contaminants often result from improper dumping and waste disposal practices by manufacturing, mining, and waste disposal companies. For example, the Anaconda Aluminum company in Montana contaminated local water sources with lead and chromium, while Gulf States Utilities in Louisiana discharged toxins, including benzene, into marshlands.

To address the issues caused by industrial wastewater, it is crucial to neutralize its toxicity through adequate treatment using physical, chemical, and biological methods. This treatment process aims to recycle the water for conservation purposes. Advanced biodegradation techniques employ a mixed culture of bacteria, such as Pseudomonas putida and Staphylococcus hominis, to break down pollutants. Additionally, fungal strains like Phanerochaete chrysosporium produce non-specific enzymes that contribute to the degradation of dyes in wastewater.

To mitigate the environmental impact of industrial waste, it is essential to implement proper waste management strategies and treatment methods. The Ministry of Environment in each province plays a regulatory role by developing policies and regulations based on scientific research and conducting compliance activities to ensure the safe discharge of industrial waste.

Agricultural processes

Agriculture is the single largest user of freshwater on a global basis, accounting for 70% of water withdrawals worldwide. It is a major cause of degradation of surface and groundwater resources through erosion and chemical runoff. Farms discharge large quantities of agrochemicals, organic matter, drug residues, sediments, and saline drainage into water bodies.

Agricultural pollution is both a direct and indirect cause of human health impacts. The WHO reports that nitrogen levels in groundwater have grown in many parts of the world as a result of "intensification of farming practice". This phenomenon is well known in parts of Europe, where more than 10% of the population is exposed to nitrate levels in drinking water that exceed the 10 mg/l guideline.

The associated agrofood-processing industry is also a significant source of organic pollution in most countries. Fish excreta and uneaten feeds from fed aquaculture diminish water quality. Increased production has combined with greater use of antibiotics, fungicides, and anti-fouling agents, which may contribute to polluting downstream ecosystems. Eutrophication caused by the accumulation of nutrients in lakes and coastal waters impacts biodiversity and fisheries.

Agricultural conservation is best practiced through a systems approach, where multiple pollutants can be controlled by implementing carefully tailored systems of conservation practices. Buffer strips are a well-established technology. Vegetated filter strips at the margins of farms and along rivers are effective in decreasing concentrations of pollutants entering waterways. Integrated systems in which crops, vegetables, livestock, trees, and fish are managed collectively can increase production stability, resource use efficiency, and environmental sustainability.

Nutrient management practices include targeting fertilizer and manure application via soil testing, crop-specific calibration, and timing applications to maximize uptake and minimize runoff. Storing livestock manure in lagoons, covered stockpiles, or protected upland areas minimizes runoff risks.

Sewage and wastewater

One of the primary concerns with sewage and wastewater is the presence of pathogens, bacteria, and viruses. These microorganisms can cause waterborne diseases such as cholera, typhoid, hepatitis, and dysentery, which, according to the World Health Organization, lead to over 3.4 million deaths annually. In the United States, EPA estimates indicate that 3.5 million Americans experience health issues due to sewage-laden coastal waters each year. Sewage-treatment processes aim to reduce pathogen levels, but they are not always completely effective, and untreated sewage can contaminate water sources, causing a range of health issues.

In addition to pathogens, sewage and wastewater often contain a cocktail of toxic chemicals, including heavy metals, pharmaceuticals, microplastics, and endocrine disruptors. These chemicals can have detrimental effects on aquatic life, leading to habitat loss, reduced biodiversity, and even the creation of "dead zones" where oxygen levels have been depleted by excessive algae growth fueled by nutrient pollution. This nutrient pollution, caused by excess nitrogen and phosphorus in water, is the leading threat to water quality worldwide and can have far-reaching consequences for aquatic ecosystems.

The improper treatment and release of sewage and wastewater is a global issue. According to the United Nations, more than 80% of the world's wastewater flows back into the environment without proper treatment. This figure is even higher in developing countries, where less than 5% of domestic and urban wastewater may be treated before release. The economic and health impacts are significant, with polluted drinking water increasing treatment costs and endangering those who rely on clean water for their livelihood, such as in the commercial fishing and tourism industries.

To address sewage and wastewater pollution, it is imperative to improve wastewater treatment infrastructure and processes. This includes investing in treatment facilities, implementing stricter regulations, and promoting sustainable practices that reduce the release of harmful substances into our waterways. By doing so, we can protect aquatic ecosystems, safeguard public health, and ensure the long-term sustainability of our water resources.

Microplastics and pharmaceuticals

Microplastics are tiny plastic particles, typically less than 5 mm in size, which can come from a variety of sources. One significant source is the breakdown of larger plastic items, such as water bottles, fishing gear, and microbeads found in some personal care products. These microplastics can take hundreds of years to degrade naturally and have become pervasive in our oceans, rivers, and even drinking water. They can be ingested by marine organisms, leading to blockages and starvation, and they can also absorb and release toxic chemicals, further contaminating the water and impacting the food chain. To prevent microplastic pollution, it is crucial to reduce plastic waste and improve waste management practices. This includes recycling and properly disposing of plastic items, as well as supporting the development and use of biodegradable alternatives. Additionally, implementing better filters in washing machines can help capture microplastics from synthetic clothing, preventing them from entering waterways.

Pharmaceutical pollution refers to the presence of pharmaceutical drugs and their metabolites in water bodies. This type of pollution occurs when people flush medications down the drain or when drugs are excreted from our bodies and enter the sewage system. Many wastewater treatment plants are not equipped to remove all pharmaceutical compounds, allowing these chemicals to persist in the water. The impact of pharmaceutical pollution on aquatic life can be significant, affecting reproduction, growth, and behavior. Additionally, there are potential risks to human health if these contaminants accumulate in the food chain or impact drinking water sources. To prevent pharmaceutical pollution, proper medication disposal methods should be encouraged. This includes returning unused or expired medications to designated collection points or pharmacies, ensuring they are safely incinerated or disposed of as hazardous waste.

Additionally, public awareness campaigns can educate people about the impacts of pharmaceutical pollution and promote responsible use and disposal practices. It is also important to support research and development into advanced wastewater treatment technologies that can effectively remove pharmaceutical compounds, protecting our water resources and the environment. Regular monitoring of water quality can help identify areas at risk and guide management decisions to mitigate the impacts of pharmaceutical pollution.

In summary, microplastic and pharmaceutical pollution are significant water contaminants that require targeted prevention strategies. By addressing these issues through improved waste management, responsible product design, and public awareness, we can reduce their presence in our waterways and mitigate their ecological and health impacts. Preventing these pollutants from entering our water systems is a critical step towards ensuring the health and sustainability of our planet's aquatic environments and safeguarding human well-being.

Frequently asked questions