Water Pollution: Points To Consider For Cleaner Oceans

Water pollution is the contamination of water bodies, including lakes, rivers, oceans, and groundwater, which has negative impacts on their use. It is predominantly caused by human activities, with over 80% of the world's wastewater released back into the environment without treatment. Water pollution can be classified as point source or non-point source. Point source pollution refers to contamination from a single, identifiable source, such as a storm drain, wastewater treatment plant, or oil spill. Non-point source pollution, on the other hand, is more diffuse, resulting from the cumulative effect of small amounts of contaminants gathered from a large area, such as agricultural runoff or stormwater runoff. The introduction of pollutants, whether from point or non-point sources, has severe consequences, including the degradation of aquatic ecosystems, the spread of water-borne diseases, and economic losses.

Industrial waste

Non-hazardous waste includes things like rubbish and debris. However, 'non-hazardous' does not necessarily mean it is safe for the environment. For example, biodegradable compounds such as paper, leather, and wool can be considered non-hazardous, but they are not fine for the environment.

The types of industrial waste generated include cafeteria garbage, dirt and gravel, masonry and concrete, scrap metals, trash, oil, solvents, chemicals, weed grass and trees, wood and scrap lumber, and similar wastes.

Industrial solid waste - which may be solid, liquid, or gases held in containers - can be released into the environment in various ways. It can be dumped directly into bodies of water, or it can leak into the environment from industrial dumps, sewage leakages, and landfills.

The production of industrial goods generates wastewater that can be contaminated with toxic substances. This wastewater is often released untreated into nearby public waters. In some cases, it is first treated by industrial wastewater recycling systems and is then either reused or disposed of in an environmentally friendly way. However, in many parts of the world, environmental policy is lacking, and the illegal discharge of wastewater from industry into rivers and lakes is common.

The improper treatment and direct release of hazardous industrial effluents into sewerage drains can cause irreversible damage to the ecosystem. It can pollute groundwater and other major water bodies, causing adverse effects on the health of animals and aquatic life. It can also lead to environmental pollution in the air, on the land surface, and in the soil.

There are technologies available to treat industrial wastewater, such as membrane systems and vacuum distillation systems. However, the implementation of these systems can depend on factors such as the type of pollution, the amount of wastewater, and the required quality of the treated water.

Sewage and runoff

Water pollution from sewage and runoff is a critical issue that poses significant risks to both human health and the environment. The problem is pervasive, affecting waterways ranging from creeks and bays to lakes and oceans.

Sewage

Untreated human sewage is a major health hazard, containing harmful pathogens such as salmonella, hepatitis, dysentery, cryptosporidium, and other infectious diseases. These pathogens can cause various illnesses, including gastroenteritis and ear infections, as well as cholera, giardia, and typhoid. Accidental or illegal releases from sewage treatment facilities, as well as ageing and overwhelmed sewage systems, contribute to the presence of harmful sewage in our waterways.

Runoff

Runoff occurs when rainfall or snowmelt moves over and through the ground, picking up and carrying pollutants such as debris, chemicals, and other toxins into water bodies. This can include nonpoint source pollution, where rainwater and irrigation wash chemicals, fertilizers, and pesticides into local streams, rivers, and lakes. Urban areas, with their vast impervious surfaces such as roads, sidewalks, and parking lots, contribute significantly to runoff by increasing the volume of water flowing into drainage systems and carrying pollutants along the way.

Preventive Measures

To reduce water pollution from sewage and runoff, several preventive measures can be implemented:

• Citizens can divert sump pump outlets and downspouts into rain barrels, artesian wells, or rain gardens to reduce the burden on sewer systems.
• Implementing permeable surfaces, such as porous pavements, can help reduce runoff by allowing water to penetrate and get absorbed into the soil.
• Green infrastructure, including the use of native vegetation, shrubs, and trees, can help prevent erosion and naturally filter and absorb harmful chemicals before they reach waterways.
• Properly disposing of hazardous wastes, maintaining vehicles to prevent fluid leaks, and reducing the use of fertilizers can minimize the amount of pollutants entering water bodies through runoff.

Oil spills and leaks

Oil spills can have disastrous consequences for the environment, economy, and society. They can harm sea creatures, ruin beaches, and make seafood unsafe to eat. Oil penetrates the structure of the plumage of birds and the fur of mammals, reducing its insulating ability and making them more vulnerable to temperature changes and less buoyant in the water. Oil spills can also cause respiratory and reproductive problems in humans, as well as liver and immune system damage.

Cleanup and recovery from an oil spill are challenging and can take weeks, months, or even years. Factors that influence the cleanup process include the type of oil spilled, the temperature of the water, and the types of shorelines and beaches involved. Additionally, cleanup activities can never remove 100% of the spilled oil, and scientists must be careful not to cause additional harm during the process.

Oil pollution can also come from land-based sources such as factories, farms, and cities. Oil can enter water bodies through stormwater runoff, which occurs when rainfall washes oil, grease, and other contaminants from impermeable surfaces into waterways. Improperly treated wastewater from industrial operations and spills in fuel depots can also contribute to oil pollution. Oil can even seep naturally from the bottom of the ocean through fractures known as seeps or from eroding sedimentary rocks.

Agricultural pollution

Agriculture is the single-largest user of freshwater resources, using a global average of 70% of all surface water supplies. It is also a major cause of degradation of surface and groundwater resources through erosion and chemical runoff.

The use of pesticides and chemical fertilizers in agriculture can contaminate both groundwater and surface water. The global market in pesticides is worth more than USD 35 billion per year, and some countries—such as Argentina, Malaysia, South Africa, and Pakistan—have experienced double-digit growth in the intensity of pesticide use. The use of pesticides and fertilizers has increased dramatically in many countries due to the pressure to produce enough food, which has resulted in expansion into marginal lands.

In addition to pesticides and fertilizers, organic livestock waste, antibiotics, silage effluents, and processing wastes from plantation crops can also contaminate water. Increased production has combined with greater use of antibiotics, fungicides, and anti-fouling agents, which may contribute to polluting downstream ecosystems. Nitrate from agriculture is now the most common chemical contaminant in the world's groundwater aquifers.

There are ways to mitigate the impact of agricultural pollution. For example, using drip irrigation instead of furrow irrigation decreases the amount of water lost to evaporation and allows better control of the amounts of pesticides and nutrients added to irrigation water. Storing livestock manure in lagoons, covered stockpiles, or protected upland areas minimizes runoff risks.

Microplastics and other waste

Microplastics are microscopic plastic particles that are less than 5 mm in length. They can come from larger plastic pieces that break down into smaller fragments, or they can be intentionally designed as microbeads, which are used in health and beauty products. These microbeads are small enough to pass through water filtration systems and end up in oceans and lakes, where they pose a threat to aquatic life. Aquatic organisms and birds can mistake microplastics for food, leading to ingestion, which can be harmful or even fatal. The entanglement effect, caused by marine organisms becoming entangled in plastic debris, also poses a significant threat.

Microplastics have been found in natural freshwater systems, including wetlands, lakes, and rivers worldwide. They are influenced by anthropogenic factors, such as economic activity, and environmental factors, including the surrounding environment, currents, and weather conditions. For example, after a typhoon, the average microplastic concentration in oysters more than doubled, demonstrating the impact of meteorological events on microplastic abundance.

The problem of microplastics in water is particularly acute in regions with high population densities and intensive anthropogenic activities. Urbanized and industrialized areas, such as those near Scotland, have been found to have the highest concentrations of microplastics in their seawater. Additionally, the polar regions are also affected by microplastic pollution, with Antarctica experiencing microplastics in freshly fallen snow for the first time in 2022.

To address the issue of microplastics in water, individuals can play a crucial role by reducing their plastic consumption and properly disposing of plastic waste. Recycling and reusing plastic products are effective ways to minimize the presence of microplastics in water. Supporting products made with biodegradable materials and sustainable packaging can also help. However, it is important to recognize that significant change will require large companies and the food industry to adopt more sustainable practices and packaging alternatives.

Aside from microplastics, other waste products also contribute to water pollution. The improper disposal of solid waste, including garbage, electronic waste, and construction debris, is a major source of water pollution. This issue is especially prevalent in developing countries that lack the necessary infrastructure or regulations for proper waste management. Solid waste pollution not only damages aquatic ecosystems but also poses a direct threat to the health of wildlife.

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