Finding Clean Water: Rivers With The Least Pollution

Rivers are indispensable to life on Earth, providing drinking water to billions of people and homes to precious wildlife. However, water pollution remains one of the biggest environmental challenges facing the planet. While some rivers flow with pristine water, others have become cesspools of industrial and human waste, threatening the health and livelihoods of those who depend on them. This text introduces the topic of river water pollution, exploring which rivers have the least polluted water and the efforts made to restore the cleanliness and biodiversity of these vital waterways.

The Thames: from biologically dead to cleanest in the world

The River Thames is considered one of the cleanest rivers in the world flowing through a major city. This is a remarkable feat considering that, in the 1950s, the Thames was declared "biologically dead" due to high levels of human and industrial waste. The turning point came in 1957, when surveys found that the river was unable to sustain life.

The Thames has a long history of pollution, dating back to medieval times when it became a dumping ground for waste and sewage. The situation worsened during the Second World War when bombings destroyed parts of the sewage network, allowing raw sewage to enter the river. The river's tributaries were reduced to running sewers, and the river itself became heavily contaminated with a range of heavy metals and industrial waste. This toxic environment led to dangerously low levels of dissolved oxygen, making it impossible for most fish and other aquatic life to survive.

Recognising the severity of the problem, policymakers and scientists began working towards restoring the Thames to health. In 1976, a pivotal step was taken when all sewage entering the Thames was treated, and legislation between 1961 and 1995 helped raise water quality standards. The privatisation of water companies and the establishment of the National Rivers Authority in 1989 further strengthened the river's protection and recovery.

Today, the Thames boasts a thriving biodiversity, with over 125 species recorded in its waters, including fish and occasionally even whales. The river's cleanliness and increased oxygenation have also enhanced its popularity for activities such as rafting and hiking. However, despite this remarkable recovery, there are ongoing challenges, including pollution, plastic waste, and the pressures of a growing population. Continuous efforts and investments are needed to maintain and further improve the health of the Thames.

The Caragh: Ireland's clean river

Ireland is known for its clean, quiet landscapes, and the Caragh River is a testament to that. Located in southwestern Ireland, in County Kerry, the Caragh River is renowned for its pristine water and lush surroundings. Flowing through verdant farmland and picturesque greenery, the Caragh is a beloved destination for outdoor enthusiasts and nature lovers alike.

The Caragh River stands out for its remarkably low levels of pollution. While many rivers around the world struggle with industrial and agricultural pollution, the Caragh remains relatively untouched. Its water is so clean that it is safe to drink, and it boasts a vibrant ecosystem teeming with plant and animal life. This includes rare species such as the Kerry Slug and the Natterjack toad. The river is also a top fishing spot, attracting anglers from near and far in search of salmon and trout.

The Caragh has a catchment area of approximately 66 square miles (170 square kilometres). It drains the southern slopes of Macgillicuddy's Reeks and several small loughs before entering Lough Caragh. As it leaves Caragh, the river flows for about two miles to the tide at Rossbehy Creek on Dingle Bay. The river is managed by K R D Fisheries Ltd downstream of the lough, while the upper section is overseen by the Glencar Hotel.

The Caragh River holds cultural and ecological significance for the region. Parts of the river are protected under a national law for conservation, falling within the boundaries of the Killarney National Park, MacGillycuddy's Reeks, and Caragh River Catchment Special Area of Conservation. This protection ensures the river's longevity and helps maintain its pristine condition.

The Caragh River serves as an example of how rivers can thrive when humanity works in harmony with nature. Through conservation efforts and responsible management, the Caragh has become a haven for wildlife and a source of enjoyment for those who appreciate its natural beauty. It is a reminder that with dedication and care, it is possible to preserve and protect our precious water sources for future generations to enjoy.

The Tara: cleanest river in the world

The Tara River, which flows through the Balkan countries of Montenegro and Bosnia and Herzegovina, is known as the "Jewel of Europe" and is considered the cleanest river in the world. The river cuts through mountainous areas and forms the deepest canyon in Europe, which is a UNESCO World Heritage Site. The Tara River Canyon boasts a diverse landscape, featuring rocky and pebbly terraces, sandy beaches, high cliffs, and over 80 large caves.

The river's water quality is exceptional, and it is known for its unique ecological system. The river is home to a vibrant array of plant and animal life, including primaeval species. The Tara, together with the Drina River, is Europe's main habitat and spawning ground for the huchen fish (Hucho hucho). The river's pristine condition can be attributed to the successful opposition to dam construction and flooding, with the public and international scientists uniting to protect this natural treasure.

The Tara River is a popular destination for river rafters and hikers from around the world. The rafting route offers a range of options, from a one-day trip with steep elevation drops and thrilling rapids to a longer journey that takes in the river's breathtaking scenery, including waterfalls, an old Roman road, and the Lever Tara. The river is also recognised as a UNESCO World Heritage Site, ensuring its protection for future generations.

While the Tara River is renowned for its cleanliness, other rivers have also made significant strides in reducing pollution. Rivers like the Thames in England and the Cheonggyecheon in Seoul have undergone successful restoration projects, improving water quality and bringing life back to their waters. These success stories give hope that with dedicated efforts, we can restore and protect our precious river ecosystems worldwide.

The Ganges: sacred but severely polluted

The Ganges River, known as the Ganga in India, is considered the most polluted river in the world. It stretches from the Himalayan foothills to the Bay of Bengal and provides water to approximately 40% of India's population, or about 500 million people, which is more than any other river in the world. The river is sacred to Hindus, and many believe that being cremated on its banks and floating down the river will cleanse the deceased of their sins and carry them to salvation. However, this has contributed to the river's pollution, as an estimated 40,000 bodies are cremated annually and deposited into the Ganges in the holy city of Varanasi alone.

In addition to human remains, the Ganges also receives significant amounts of plastic and industrial waste, including wastewater from factories, tanneries, chemical plants, textile mills, slaughterhouses, and hospitals. The construction of dams along the river has also altered its natural flow and submerged substantial areas of nearby forest, further contributing to the pollution. The river's water quality is so poor that it has been linked to various waterborne diseases, including dysentery, cholera, hepatitis, and severe diarrhea, which is a leading cause of death among children in India.

Recognizing the severity of the issue, the Indian government has launched several initiatives to clean up the river, including the Namami Gange project, which received an estimated $460 million in funding by 2016. However, these efforts have largely failed to produce significant results, and critics attribute this to corruption and mismanagement. Restoring the Ganges to its natural state will require a long-term commitment and cooperation from all users, as well as a shift in perception and rituals surrounding the sacred river.

Despite the challenges, there are some positive developments. For example, electric crematoria have been constructed as an alternative to traditional wood-burning pyres, reducing the amount of waste entering the river. Additionally, companies like Renewology have been installing mobile plastic-waste-to-energy systems along the Ganges' tributaries to collect and convert plastic waste into fuel. These efforts demonstrate a growing awareness of the need to protect and restore the sacred Ganges River, which is revered by many but severely polluted.

The Citarum: lead content 1000x higher than safe levels

The Citarum River in Indonesia is the second most polluted river in the world. Its lead content is a staggering 1000 times higher than safe levels as per the US Environmental Protection Agency standard for drinking water. To put this into perspective, the World Health Organization (WHO) estimates that at least 2 billion people globally consume water contaminated with faeces, which is a severe health hazard.

Lead is a highly toxic substance, and exposure to high levels of it can cause severe damage to the brain, kidneys, and nervous system. Lead poisoning can be particularly harmful to children, causing irreversible cognitive and behavioural problems. The high lead levels in the Citarum River are likely due to a combination of industrial and agricultural runoff, improper waste disposal, and sewage discharge.

The Citarum is not an isolated case; many rivers worldwide are suffering from similar issues. For instance, the Ganges River in India, sacred to Hindus, is considered the most polluted river globally due to industrial and agricultural pollution, sewage, and oil spills. The Pasig River in Manila, the Philippines, has also been declared "biologically dead" due to the daily influx of sewage and garbage from the surrounding communities.

However, there is some hope. Several rivers have been successfully restored, including the Thames in London, which was once so polluted that it was considered biologically dead. After implementing measures such as banning factories from dumping pollution, installing water treatment plants, and improving the drainage system, the Thames is now widely regarded as the cleanest river flowing through a major city. The Caragh River in Ireland and the Cheonggyecheon River in Seoul have also been mentioned as examples of rivers with very little pollution.

To ensure the health and sustainability of our rivers, it is crucial to address the root causes of pollution. This includes implementing proper waste management practices, reducing industrial and agricultural runoff, and investing in city sanitation measures. By taking collective action and prioritizing the health of our rivers, we can work towards restoring these vital waterways for the benefit of the environment and the billions of people who depend on them.

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