Kiera Jefferson
Water is essential for life, but human activity has poisoned many of the world's rivers, oceans, and lakes. The most polluted body of water is subjective, but the Ganges River in India is widely considered one of the most polluted rivers globally, with billions of litres of untreated sewage and toxic waste dumped into it daily. The sacred river serves over two billion people, and communities frequently exposed to it have reported higher incidences of waterborne diseases. The Citarum River in Indonesia is also a contender for the most polluted waterway, with toxic waste from over 2,000 factories and a dense population contributing to its degradation. The Pacific Ocean, the Yellow River in China, the Mississippi River in the US, and Lake Victoria in Africa are also among the world's most polluted bodies of water.
Explore related products
What You'll Learn
The Pacific Ocean: Sewage and garbage patches
Water pollution is one of the most pressing environmental challenges facing the planet. It is estimated that more than 80% of the world's wastewater ends up in oceans, rivers, and lakes. The Pacific Ocean is the most polluted of the five official oceans on the planet. Sewage is the primary cause of pollution in the Pacific Ocean. Every year, 21,675 tonnes of biochemical oxygen demand (BOD) and 12,252 tonnes of suspended solids (such as decaying organic matter) enter the ocean. These sewage spills not only destroy vulnerable marine habitats but also harm local communities on nearby Pacific islands.
The Great Pacific Garbage Patch, located between Hawaii and California, is a massive accumulation of plastic waste in the Pacific Ocean. It is the largest collection of ocean plastic globally, with an estimated mass of 100,000 tonnes of plastic, equivalent to over 740 Boeing 777s. The patch covers approximately 1.6 million square kilometres, or three times the size of France. The plastic in the patch is not limited to large pieces but also includes microscopic particles called microplastics, which are often not detectable by satellite imagery or casual observers. These microplastics can remain suspended in the upper water column, making the water appear like a cloudy soup.
The Great Pacific Garbage Patch is a result of the North Pacific Subtropical Gyre, a large system of swirling ocean currents, including the California Current, the North Equatorial Current, the Kuroshio Current, and the North Pacific Current. The circular motion of these currents draws debris into the centre, where it becomes trapped. The patch is not a solid mass but a scattered accumulation of plastic pollution, with buoyant plastic influenced by factors such as wind speed, sea state, and buoyancy. While larger pieces of plastic resurface more rapidly, microplastics can persist in the region and have been measured since the 1970s.
The garbage patch in the Pacific Ocean is not an isolated problem. The Indian Ocean, for example, has its own garbage patch spanning at least five million square kilometres, and it is also a hotspot for oil spills, with approximately 40% of all petroleum spills occurring in this region. Rivers, such as the Yangtze, the Citarum, and the Mississippi, are also among the most polluted waterways globally due to industrial wastewater discharge, agricultural waste, and human activities. These polluted waterways have severe environmental, economic, and health consequences, impacting aquatic life, soil quality, and human health.
Industries' Polluting Practices: Air and Water at Risk
You may want to see also
Explore related products
The Indian Ocean: Oil spills and plastics
The Indian Ocean is one of the most polluted bodies of water in the world. It is a hotspot for oil spills and plastic pollution. In 2020, a Japanese ship, MV Wakashio, ran aground on a coral reef off the southeast coast of Mauritius and began leaking heavy fuel oil. This oil spill endangered rich marine ecosystems that are home to 1,700 species, including 800 types of fish, 17 kinds of marine mammals, and two species of turtles. The pristine turquoise waters of Mauritius turned black, and its mangrove wetlands became polluted, severely affecting marine and coastal ecosystems.
The Indian Ocean is particularly vulnerable to oil spills due to its increasing role in oil exploration and transit. Approximately 40% of all petroleum spills occur in this body of water, and the sticky tar lumps that result can smother wildlife. In addition to oil spills, the Indian Ocean also faces a significant problem with plastic pollution. Some of the most plastic-polluted rivers in the world empty into the Indian Ocean, and the high population densities of surrounding countries contribute to the mismanagement of plastic waste. It is estimated that around 15 million tonnes of plastic enter the Indian Ocean Region (IOR) each year, threatening ecologically sensitive coral reef regions.
The X-Press Pearl container ship spill off the coast of Sri Lanka in 2021 is another example of plastic pollution in the Indian Ocean. The ship was carrying 78 tonnes of plastic nurdles, which were released into the ocean. Plastic debris is the most common and exponentially increasing human pollutant in the world's oceans, and the impact of plastic pollution in the Indian Ocean is particularly concerning due to the unique atmospheric, oceanographic, and topographic features that control plastic distribution, such as reversing wind directions due to monsoons, fronts, and upwelling.
While there have been efforts to combat plastic pollution in the Indian Ocean, such as bans or regulations on plastic use and beach clean-ups, the problem persists. The Indian Ocean's "garbage patch" now stretches over at least five million square kilometres, posing a massive environmental threat to the region's vulnerable habitats and local communities. The response to pollution in the Indian Ocean has been significant, with Indian Coast Guard director general V S Pathania emphasizing the need for collaboration among stakeholders to minimize damages to the marine ecosystem and protect ecologically sensitive regions.
Food Waste: Water Pollution's Unseen Contributor
You may want to see also
Explore related products
The Yangtze River: Industrial wastewater and agricultural chemical fertiliser
The Yangtze River, the world's third-longest river and China's largest, is an important drinking water source for almost 600 million people. It is also home to a third of China's endangered species and 40% of its rare or endangered plants. However, the river has been facing significant pollution issues due to increased human and industrial activity, as well as agricultural development.
Industrial wastewater is one of the major contributors to the pollution of the Yangtze River. The rapid growth of large and medium-sized cities along the river, particularly in the midstream and downstream areas, has led to a high concentration of heavy metals in the water. These heavy metals, including zinc, arsenic, cadmium, lead, copper, nickel, and chromium, pose serious health risks to nearby inhabitants. Their presence in the water has been linked to human activities and industrial developments.
Agricultural activities have also played a significant role in polluting the Yangtze River. The use of chemical fertilisers, pesticides, and agricultural films has resulted in non-point source pollution, which has detrimental effects on water quality. Studies have shown that an increase in agricultural fertiliser application directly impacts water pollution. Excess nutrients from fertilisers, such as nitrogen and phosphorus, enter the water body through soil denudation, surface runoff, and leaching loss. This process aggravates the eutrophication of surface water bodies and causes nitrate pollution of groundwater, threatening the overall health of the aquatic ecosystem.
In recent years, efforts have been made to address the pollution in the Yangtze River Basin. The World Bank has approved a US$200 million loan to enhance ecological protection and reduce water pollution in Hubei Province, which covers a large portion of the river basin. The program aims to strengthen ecosystem management, improve wastewater treatment, and reduce pollution from plastics, animal manure, and agricultural sources. The total financing for the project is expected to reach US$1.1 billion over a five-year period, demonstrating a strong commitment to tackling this pressing environmental challenge.
Cleaning Polluted Water: What's the Cost?
You may want to see also
Explore related products
The Ganges River: Raw sewage, chemicals, and plastic waste
Water pollution is one of the most pressing environmental challenges facing the planet. The Ganges River, the largest river in India, is a prime example of a body of water suffering from severe pollution. The river traverses a distance of over 2500 kilometres from the Himalayas to the Bay of Bengal, providing water to approximately 40% of India's population across 11 states. However, the Ganges has become a toxic waterway due to various pollutants, including raw sewage, chemicals, and plastic waste.
Raw sewage is one of the major contributors to the pollution of the Ganges River. In 2010, the Indian government announced a $4 billion campaign to ensure that no untreated municipal sewage would enter the river by 2020. The Ganga Action Plan (GAP), launched in 1985, aimed to improve water quality through the interception, diversion, and treatment of domestic sewage. Despite these efforts, sewage continues to be a significant issue. During the 2025 Kumbh Mela, for example, the National Green Tribunal reported that the level of faecal coliform bacteria in the Ganges at Prayagraj was 1400 times above the permissible limit.
Chemicals from industrial waste and agricultural activities also play a significant role in polluting the Ganges. The river receives toxic industrial chemical wastes from factories and industrial plants along its banks. Additionally, agricultural pesticides and chemical fertilisers used in the surrounding areas leach into the river, further degrading its water quality. The Indian government has been working towards the closure and relocation of some of these industrial plants, but the impact of past pollution remains.
Plastic waste is another critical pollutant in the Ganges River. Microplastics, such as polyethylene, polystyrene, and polypropylene, have been found in high concentrations along the riverbanks and in the water. These plastics originate from discarded plastic bags, food packaging, milk bottles, and other single-use plastic products. The plastics bind to harmful pollutants and metal nanoparticles, increasing their toxicity and posing a threat to the myriad life forms that depend on the river. The problem is exacerbated by plastic pollution from ghost gear—derelict, discarded, lost, or abandoned fishing gear in aquatic systems.
The pollution of the Ganges River has severe consequences for both human health and the environment. The river is a source of water, income, and nutrition for millions of people in India and Bangladesh. However, the pollutants in the water pose significant health risks, and the declining fish stocks due to pollution threaten the livelihoods of those dependent on inland fisheries. Despite various initiatives and efforts to clean the river, such as the Namami Gange project, the pollution of the Ganges remains a persistent problem, highlighting the urgent need for effective solutions to address this environmental crisis.
Emptying Polluted Water: Safe Pumping Station Methods
You may want to see also
Explore related products
The Mississippi River: Agricultural runoff and chemical fertiliser
Water pollution is one of the most pressing environmental challenges facing the planet. While the Pacific Ocean is the most polluted out of the five official oceans, there are many rivers that are also severely polluted. One of these is the Mississippi River, which is one of the most polluted rivers in the United States.
Agricultural runoff and chemical fertiliser are major contributors to the pollution of the Mississippi River. The river's basin is a hub of industrial farming, which generates large amounts of manure. This manure, along with chemical fertilisers, is washed into the river through surface runoff. Nitrogen and phosphorus are the most common agricultural pollutants found in the river, and they have severe ecological consequences.
The excess nutrients in the water cause a process called eutrophication, leading to the formation of algal blooms. These blooms block sunlight from penetrating the water's surface, inhibiting photosynthesis. When the algae die, they sink to the bottom, where bacterial decomposition consumes oxygen, leading to the asphyxiation and death of marine life. This phenomenon is known as a "dead zone", and it has been occurring in the Gulf of Mexico since the 1970s.
The agricultural pollution of the Mississippi River is not easy to regulate due to its non-point source nature. While the Clean Water Act (CWA) addresses both point source and non-point source pollution, regulating the latter is much more challenging and ineffective. Additionally, agricultural runoff has been exempted from the Clean Water Act for decades, making it difficult to hold farmers legally accountable for the pollution they generate.
To address the issue, the Environmental Protection Agency (EPA) has been encouraging states to implement numerical limits on the amount of chemicals allowed in local waterways. However, as of 2011, only two out of nine key farm states that feed into the Mississippi River had taken action, and even then, only for lakes rather than rivers or streams. In 2009, the Department of Agriculture introduced an incentive program to encourage grass-roots solutions, such as wetlands creation and educating farmers on just-in-time fertiliser application. This program has shown promising results, with a nearly 50% decrease in phosphorus and nitrogen in surface runoff from 150,000 acres enrolled.
Water Pollution: A Historical Problem, What's Next?
You may want to see also
Frequently asked questions
It is difficult to definitively state which body of water is the most polluted, but the Ganges in India is a strong contender. The river is sacred to locals, who believe it will cleanse them of their sins, but it is also a dumping ground for human and animal waste, pesticides, fertilizers, industrial metals, and ashes from cremated bodies.
The Citarum River in Indonesia is considered by some to be the most polluted waterway in the world. Over 2,000 industrial facilities pour untreated waste into the river, which supplies drinking water to millions of people. The Pacific Ocean is the most polluted of the five official oceans, with 21,675 tonnes of biochemical oxygen demand (BOD) entering these waters each year. The Yangtze River in China is also one of the most polluted bodies of water, due to industrial wastewater discharge and agricultural chemical fertilizer.
Water pollution is caused by a variety of human activities, including industrial waste, sewage, poor waste management, agricultural runoff, and the dumping of plastic and chemicals. Pharmaceutical pollution is also a significant and growing problem, with a 2022 study finding that it is rampant in waterways around the globe.
