Understanding Sewage Water Pollution: Causes And Effects

Sewage water pollution is a critical issue that poses a threat to both human health and natural ecosystems. It occurs when untreated or inadequately treated wastewater is released into water bodies, including rivers, lakes, and oceans. This wastewater contains a toxic cocktail of contaminants, such as pathogens, heavy metals, pharmaceuticals, microplastics, and endocrine disruptors, which can have far-reaching consequences for aquatic life, biodiversity, and public health. The impact of sewage pollution on nature has been deadly, with cases of mayflies being wiped out and algal blooms thriving while threatening the survival of other species. The problem is exacerbated by aging infrastructure, poorly planned development, and insufficient investment in wastewater treatment systems, leading to frequent overflows and leaks. As a result, waterborne illnesses and infections affect millions of people annually, with low-income communities being disproportionately at risk.

Sewage in Britain's waterways

Sewage pollution refers to the presence of contaminants in water bodies, including rivers, lakes, and oceans, due to the discharge of untreated or partially treated wastewater. It poses significant risks to both human health and the environment.

In recent years, Britain's waterways have been plagued by sewage spills, with privatised water companies facing accusations of prioritising profits over the environment. The issue has sparked widespread public outcry and led to growing concerns about the state of the country's bathing water quality.

In 2023, water companies in England discharged untreated sewage into rivers and seas for 3.6 million hours, a significant increase from 1.75 million hours in 2022. This has polluted streams, rivers, and coastlines, damaging ecosystems and deterring tourists and water enthusiasts. Sewage spills have been linked to the decline of insect populations, such as mayflies, and the promotion of toxic blue-green algal blooms, which can lead to the deaths of various species and impact the functioning and biodiversity of ecosystems.

The Holmyard family, owners of Europe's largest offshore mussel farm in Lyme Bay, has been affected by sewage pollution. Despite being located almost 5 kilometres from the shore, their farm has been contaminated by harmful bacteria, such as E. coli, leading to blocked exports and economic losses.

The frequent sewage spills have resulted from a combination of factors, including ageing infrastructure, extreme weather events, and insufficient investment in wastewater treatment facilities. Water companies have been criticised for their reliance on waterways to manage excess sewage instead of investing in proper treatment methods.

In response to the growing crisis, various parties in Britain have included plans to tackle sewage spills in their election manifestos. The Labour Party, in particular, has proposed putting water companies that dump sewage into special measures and introducing automatic fines for such practices. However, proposed amendments to the Environment Bill, such as mandating that water companies ensure raw sewage is not discharged, have been defeated in Parliament.

Human health impact

Sewage water pollution has a significant impact on human health, causing a range of diseases and health issues. It is a global issue, with the World Water Development Report 2021 highlighting the six-fold increase in freshwater usage over the past century, placing immense pressure on water quality. The report also emphasizes the role of industrialization, agricultural production, and urbanization in degrading water bodies essential for life, with 80% of untreated industrial and municipal wastewater being discharged into the environment. This has severe consequences for human health and ecosystems.

One of the primary health risks associated with sewage water pollution is the presence of waterborne pathogens. Untreated sewage water can contain harmful bacteria and viruses from human and animal waste, leading to diseases such as cholera, giardia, typhoid, and hepatitis A. These pathogens can contaminate drinking water sources, causing infections and gastrointestinal issues. Poor sanitation and inadequate wastewater treatment, particularly in developing countries, exacerbate this problem.

Chemical pollutants are another major concern in sewage water pollution. Industrial activities introduce heavy metals, such as arsenic, mercury, and lead, into water bodies, posing significant health risks. Ingestion of these toxins has been linked to cancer, hormone disruption, and altered brain function. Additionally, pesticides and nitrate fertilizers used in agriculture can contaminate water sources, leading to adverse health effects.

Microplastics, formed from the breakdown of plastic waste in water, are another emerging health concern. These tiny plastic fragments can be ingested by humans through drinking water or contaminated seafood. While research is ongoing, initial studies suggest that microplastics may trigger oxidative stress, inflammatory reactions, and metabolic disorders. Radioactive waste is another severe contaminant that can persist in the environment for millennia, posing long-term hazards to human health if not properly disposed of.

The impact of sewage water pollution on human health is far-reaching, and it is not limited to ingestion or direct contact with contaminated water. In some cases, simply living or swimming in areas with polluted water bodies can lead to health issues. For example, Legionnaires' disease, a severe form of pneumonia, has affected thousands of people in the United States, including cases in California and New York. Additionally, sewage overflows can contaminate waterways with human waste, household chemicals, and plastics, creating an ""ecological trap"" that endangers both wildlife and humans.

Waterborne pathogens

Sewage water pollution is a pressing issue that poses a significant threat to both human health and the environment. It refers to the contamination of water sources, such as rivers, lakes, and oceans, with untreated human sewage and wastewater. This pollution contains harmful pathogens, including disease-causing bacteria and viruses, which can have devastating consequences for people, animals, and ecosystems.

The health risks associated with waterborne pathogens are extensive. In developing countries, where access to safe water and sanitation is limited, waterborne diseases are a leading cause of illness and death. Diarrhea, a common symptom of waterborne diseases, is responsible for more childhood deaths than malaria, AIDS, and measles combined. Cholera, giardia, and typhoid are other examples of diseases caused by waterborne pathogens. These illnesses can lead to severe gastrointestinal problems, skin rashes, respiratory infections, and even hepatitis.

In the United States, waterborne pathogens have also taken a toll. Between 1985 and 2000, the Centers for Disease Control (CDC) documented nearly half a million cases of waterborne illness from polluted drinking water. Legionnaires' disease, caused by Legionella bacteria, has been a leading cause of hospitalizations and deaths associated with drinking water. Other pathogens, such as nontuberculous mycobacteria (NTM), have also contributed to waterborne disease outbreaks.

The sources of waterborne pathogens can vary. In addition to sewage leaks and overflows, aging and overwhelmed sewage treatment infrastructure is a significant contributor. In the United States, for example, the country's aging sewer pipes and treatment plants struggle to keep up with the increasing volume of stormwater and wastewater, leading to the release of billions of gallons of untreated wastewater each year. Additionally, industrial activities, agricultural runoff, and oil pollution from vehicles and factories further compound the problem, introducing harmful chemicals and toxins into water sources.

To address the issue of waterborne pathogens, it is crucial to prioritize investments in wastewater infrastructure and treatment facilities. This includes upgrading aging sewer systems, improving treatment processes, and ensuring proper maintenance and capacity to handle increasing demands. Additionally, protecting and expanding natural areas, such as wetlands and green spaces, can help mitigate stormwater runoff and reduce the risk of sewer overflows. Community education and access to safe water and sanitation practices are also essential to preventing waterborne diseases, especially in vulnerable and low-income communities.

Septic systems

Sewage water pollution is a pressing issue that poses a danger to human health and the environment. While significant progress has been made in treating sewage and improving water quality, challenges remain, particularly with ageing infrastructure and inadequate wastewater treatment systems. Septic systems, commonly used for wastewater treatment, can play a crucial role in addressing sewage pollution.

The impact of septic systems on water sources depends on several factors, including design, installation, maintenance, and proper usage. Systems that are poorly designed, installed, or maintained can release untreated wastewater containing harmful substances such as pathogens (e.g. E. coli), nutrients, and nitrogen into the environment. This can lead to contamination of groundwater, surface waters, and drinking water wells, posing a direct health risk to individuals, especially children, and the ecosystem.

To prevent septic systems from impacting nearby water sources, homeowners should ensure proper installation, siting, and maintenance. Consulting with professionals is recommended before making significant upgrades to septic systems. Additionally, protecting and expanding natural areas, such as planting trees, restoring wetlands, and creating green roofs, can help prevent stormwater from rushing into sewers, reducing the risk of sewer overflows and subsequent pollution.

In conclusion, septic systems play a vital role in wastewater treatment for many homeowners. While they can effectively treat wastewater and replenish groundwater supplies, improper functioning or maintenance can lead to water source contamination. By ensuring proper installation, maintenance, and taking proactive measures to protect natural areas, the impact of septic systems on water pollution can be mitigated, contributing to cleaner and safer water sources for both human and environmental health.

Water quality testing

Sewage water pollution is a serious issue that poses a threat to both human health and the environment. It is caused by the discharge of untreated or partially treated sewage into natural water bodies, such as rivers, lakes, and oceans. The impact of sewage pollution on the environment is devastating, with far-reaching consequences for the plants, animals, and insects that inhabit these ecosystems.

In the context of sewage water pollution, some of the key parameters that are tested for include:

• Bacteria and Pathogens: Sewage water is known to contain harmful bacteria and pathogens, such as E. coli and intestinal enterococci, which pose a significant risk to human health. Testing for these microorganisms is essential to ensure that water is safe for human recreation and consumption.
• Chemical Pollutants: Sewage can also be a source of chemical pollutants, including heavy metals (e.g., arsenic, mercury), pesticides, and fertilizers. These toxins can have severe health impacts, including cancer, hormone disruption, and altered brain function. Advanced analytical techniques, such as chromatography and spectroscopy, are often employed to detect and quantify these pollutants.
• Solids and Organic Matter: Sewage treatment processes typically involve the removal of large solids and organic matter through physical and biological treatment methods. Testing for these parameters helps assess the effectiveness of treatment processes and ensures that the treated water meets the required standards before being released into the environment.
• Nutrient Levels: Excessive nutrient levels, particularly nitrogen and phosphorus, can lead to eutrophication, encouraging the growth of algal blooms. These blooms can deplete oxygen levels in the water, leading to the death of aquatic organisms and disrupting the natural balance of the ecosystem.

Frequently asked questions