Water Pollution Warriors: Who's Responsible?

Water pollution is a pressing global issue that jeopardizes human health and the environment. It arises from various human activities, such as improper waste disposal, agricultural runoff, and oil spills, contaminating water sources with toxic chemicals, microorganisms, and waste. The World Health Organization (WHO) defines polluted water as water that has become unusable due to changes in its composition, making it unfit for drinking or essential purposes like agriculture. This widespread problem demands attention, as it endangers the health of millions and poses economic challenges. Addressing water pollution requires collective efforts, including reducing CO2 emissions, minimizing chemical pesticide use, properly treating wastewater, and restricting single-use plastics to protect our precious water sources and safeguard public health.

The agricultural sector

Agriculture is the single largest user of freshwater on a global basis and is a major cause of degradation of surface and groundwater resources through erosion and chemical runoff. It accounts for 70% of water withdrawals worldwide and is the largest contributor of non-point-source pollution to surface water and groundwater.

Agricultural pollution includes the discharge of large quantities of agrochemicals, organic matter, drug residues, sediments, and saline drainage into water bodies. The unsafe use of non-conventional sources of water, especially wastewater, can lead to the accumulation of microbiological and chemical pollutants in crops, livestock products, and soil and water resources. This can have severe health impacts on exposed food consumers and farm workers, and also exacerbate antimicrobial resistance.

Pesticides and fertilizers used in agriculture can contaminate both groundwater and surface water, as can organic livestock waste, antibiotics, silage effluents, and processing waste from plantation crops. Livestock and their manure also pollute the air, with manure emitting ammonia that combines with other air pollutants to create harmful solid particles.

To address these issues, the Food and Agriculture Organization of the United Nations (FAO) works closely with countries and other organizations to monitor, control, and mitigate pollution loads from agricultural activities. FAO takes a multidimensional approach to ensure that socio-economic, health, environmental, and food safety aspects are covered.

Some recommended practices to reduce agricultural pollution include:

• Nutrient management practices, such as targeting fertilizer and manure application through soil testing, crop-specific calibration, and timing applications to maximize uptake and minimize runoff.
• Using drip irrigation instead of furrow irrigation to reduce water loss and better control the amount of pesticides and nutrients added to irrigation water.
• Storing livestock manure in protected areas, such as lagoons or covered stockpiles, to minimize runoff risks.
• Implementing a systems approach to agricultural conservation, where multiple pollutants are controlled through carefully tailored systems of conservation practices.

Industrial activities

In the United States, industrial agriculture is a leading cause of water pollution. The Environmental Protection Agency (EPA) has reported that nearly half of the nation's rivers and streams are in "poor biological condition," with high levels of nutrients and algae degrading water quality. Industrial agricultural practices, such as the use of synthetic fertilizers and the accumulation of metal-rich animal waste, contribute to this degradation.

Oil refineries are another significant source of industrial water pollution. In the United States, refineries discharge approximately half a billion gallons of wastewater into waterways daily, containing pollutants such as arsenic, mercury, selenium, nitrogen, and oils. These discharges lead to harmful algae blooms and mutations in fish and other freshwater wildlife.

The European Union has also faced challenges with industrial water pollution. While overall industrial releases into water decreased between 2010 and 2022, emissions of certain pollutants, such as nitrogen and phosphorus, remain a concern. The European Pollutant Release and Transfer Register (E-PRTR) collects data on direct releases of pollutants into water from industrial and wastewater treatment operations, helping to regulate and reduce pollution levels.

To address industrial water pollution, regulations and standards, such as the Clean Water Act in the United States, are essential. However, enforcement and regular updates to these regulations are critical to keeping up with technological advancements and ensuring that industries are held accountable for their pollution levels.

Sewage and toxic waste

The release of sewage into waterways introduces a large amount of nutrients, particularly nitrogen and phosphorus, which stimulate the growth of algae. This process, known as eutrophication, can lead to the formation of algal blooms, which have detrimental effects on aquatic ecosystems. Algal blooms can block light necessary for photosynthesis, leading to the death of plants and algae. As bacteria decompose the organic matter, they consume oxygen, creating "dead zones" where aquatic life cannot survive due to a lack of oxygen. Sewage also contains pathogens, heavy metals, microplastics, and chemicals, which can cause physiological changes in fish and accumulate in the food chain, ultimately impacting human health.

Toxic waste, on the other hand, includes a range of poisonous and hazardous substances. Sources of toxic chemicals include improperly disposed of wastewater from industrial plants and chemical process facilities, which release substances such as lead, mercury, and chromium. Agricultural activities also contribute to toxic waste through the use of pesticides and surface runoff containing chemicals like chlordane, dieldrin, and heptachlor. Oil spills, both accidental and from stormwater runoff, are another significant source of water pollution, with devastating impacts on marine life and ecosystems.

The effects of sewage and toxic waste pollution extend beyond the environment and pose significant risks to human health. Unsafe water is estimated to cause the deaths of about 1 billion people annually, with waterborne pathogens from human and animal waste being a major concern. Diseases spread by contaminated water include cholera, giardia, typhoid, and Legionnaires' disease. Additionally, inadequate management of wastewater in urban, industrial, and agricultural sectors leads to microbial contamination of drinking water sources, affecting the health and sanitation of millions of people worldwide.

Addressing the issues of sewage and toxic waste pollution requires a multi-faceted approach. While wastewater treatment facilities play a crucial role in reducing pollutants, innovation in sewage management, such as waste-free toilets and resource recovery, is also necessary. Collaboration between conservationists and the human health sector is vital to tackle the global sanitation crisis and mitigate the impacts on ecosystems and human communities.

Oil spills

In the United States, the U.S. Coast Guard or the U.S. Environmental Protection Agency takes charge of the spill response, depending on where the oil spill occurs. These agencies often call on other agencies, such as NOAA and the Fish and Wildlife Service, for help and information. NOAA's Office of Response and Restoration (OR&R) provides scientific support during both oil spill response and environmental restoration efforts.

The cleanup and recovery process after an oil spill is complex and depends on several factors, including the type of oil spilled, the temperature of the water, and the types of shorelines and beaches involved. Spills may take weeks, months, or even years to clean up. During the cleanup process, air pollutants such as nitric oxides and ozone from ships can be generated.

To prevent oil spills from occurring, federal regulations have been implemented, and people who cause oil spills must pay severe penalties. Additionally, regulations call for safer vessel design, and people who manage vessels and facilities that store or transport oil must develop plans explaining how they would respond to a spill. By reducing our reliance on oil and finding alternative modes of transportation, we can also lower the risk of future oil spills.

Global warming

Water pollution is a pressing issue that poses a significant threat to both human health and aquatic ecosystems. The release of pollutants from human activities and industries contributes to global warming, and the rising temperatures further exacerbate water pollution.

Climate change, largely driven by global warming, is exacerbating water scarcity and water-related hazards. Rising temperatures disrupt precipitation patterns, leading to unpredictable rainfall, more frequent and severe floods, and prolonged droughts. These changes directly impact water quality, as higher water temperatures can facilitate the growth of harmful algae and microbes, compromising the availability of safe drinking water.

The warming of the oceans, accounting for around 93% of the planet's warming since the 1950s, is a significant consequence of increasing greenhouse gas emissions, particularly carbon dioxide. The oceans trap and store heat, affecting water temperature and circulation. This, in turn, contributes to the melting of polar ice caps, reducing the reflection of solar energy back into space and further warming the planet.

To address these challenges, cities, regions, and countries are adopting more eco-friendly and nature-based solutions. 'Blue areas', such as rivers and lakes, can provide a cooling effect, offering relief from heatwaves, especially in urban areas. Additionally, implementing climate-smart agriculture, such as drip irrigation, can help reduce the demand on freshwater supplies. Mitigating climate change by reducing greenhouse gas emissions is crucial, and adaptation strategies, including using less water, are essential to cope with the impacts of global warming on water resources.

Frequently asked questions