Water Pollution In Europe: Sources And Causes

Water pollution is a pressing issue in Europe, threatening its freshwater resources and endangering drinking water supplies. With Europe's seas covering over 11 million square kilometres and its diverse range of coastal and marine ecosystems, the sources of water pollution are diverse and varied. From industrialisation and agricultural activities to urbanisation and population changes, Europe's water bodies are under significant strain. The use of pesticides and herbicides, as well as nutrient runoff and wastewater discharges, are key contributors to water pollution, impacting both surface and groundwater sources. Climate change further exacerbates these issues, with ocean acidification and rising sea surface temperatures posing additional challenges. While progress has been made in some areas, such as improving bathing water quality and drinking water treatment, concerns remain about the conservation of wetlands, plastic litter, and the long-term health effects of microplastics.

Industrialisation and industrial discharge

Industrialisation and the associated industrial discharge are significant contributors to water pollution in Europe. The intensification of industrial activities has led to the release of various pollutants into Europe's water bodies, including heavy metals, total organic carbon (TOC), and compounds containing nutrients such as nitrogen and phosphorus. These pollutants have detrimental effects on both the environment and human health.

Heavy metals, such as cadmium, nickel, mercury, and lead, have been a particular cause for concern. While emissions of these metals have declined between 2010 and 2022, with significant decreases in lead emissions, there was a stagnation in the decline after 2016. This highlights the need for continued efforts to reduce industrial emissions.

Nitrogen and phosphorus emissions, while decreasing to a lesser extent, remain a pan-European problem. Nitrogen emissions contribute to eutrophication, and both elements are associated with agricultural activities, which further exacerbates the issue. The release of these compounds into water bodies can have severe ecological consequences and negatively impact the health of indigenous populations.

Industrialisation has also influenced river courses and their ecosystems. River straightening, for example, has occurred during industrial phases, independent of climate conditions and discharge regimes. Additionally, the construction and removal of water mills, dams, and other land reclamation projects have altered river ecosystems, impacting water quality and sustainability.

To address these issues, the European Union and its member states have implemented policies and measures, such as the Water Framework Directive (WFD) and the Industrial Emissions Directive (IED), which aim to protect Europe's water bodies from industrial emissions while supporting economic growth. However, data gaps and inconsistent reporting across countries make it challenging to fully assess the impact of industrial activities on water pollution in Europe.

Agricultural pollution

In Europe, agriculture is a major user and source of water pollution. It accounted for 59% of total freshwater use in Europe in 2017. The use of fertilisers and pesticides in agriculture has led to diffuse pollution, affecting rivers, lakes, and groundwater. Nitrate pollution, especially from agricultural fertilisers, remains a persistent issue, with western European countries with intensive agriculture showing the highest nitrate concentrations in rivers.

Pesticides from agriculture are also present in raw water used for drinking water production, raising concerns about their potential impact on human health. Additionally, the growing specialisation and concentration of crop and livestock production have contributed to increased pollution levels. For example, manure production and disposal have become significant sources of agricultural pollution. To address this, some countries have adopted incentive-based approaches, such as establishing manure quotas and national manure banks to regulate and distribute manure supplies more sustainably.

The European Union's Common Agricultural Policy (CAP), incorporated into the 1957 Treaty of Rome, aimed to increase agricultural productivity and ensure a fair standard of living for farmers. However, this policy did not initially consider the environmental implications, leading to agriculture becoming a major source of water pollution. Over time, the EU has recognised the need to integrate agricultural and environmental policies to effectively address water pollution from agricultural sources.

While there have been improvements in river quality in some European countries, the overall progress in reducing agricultural water pollution remains uneven. France, Germany, the Netherlands, and the United Kingdom have experienced severe agricultural water pollution and have adopted various measures to mitigate it. These include providing grants to farmers to reduce fertiliser and pesticide use and promoting negotiated agreements between water supply companies and farmers to improve drinking water quality. Despite these efforts, the control of agricultural water pollution remains a complex issue that requires better coordination and integration of agricultural and environmental policies.

Urban stormwater runoff

Vehicular transportation-related activities, such as emissions from cars, trucks, and buses, as well as oil and grease from roads and parking lots, can contaminate stormwater. Atmospheric deposition refers to pollutants that are emitted into the atmosphere and then deposited onto surfaces through dry or wet precipitation. These pollutants can include particulate matter, nitrogen oxides, and volatile organic compounds. Metallic building envelopes, which are commonly used in urban areas, can also contribute to stormwater pollution through the release of metals such as zinc, copper, and lead.

In addition to these sources, urban stormwater runoff can also be affected by other human activities such as industry and agriculture. Pollution from widespread sources, known as "diffuse pollution," includes nutrients and pesticides from farming activities. Industrial activities can also release pollutants into the air, which then fall back to the land and water bodies, contributing to water pollution.

The impact of urban stormwater runoff on surface water quality has been studied for several decades, and source controls have been identified as effective tools for mitigating this type of pollution. However, the identification of stormwater runoff pollution sources and their associated pollutants is a continuous process due to the constant release of new materials, chemicals, and substances into the environment.

To improve water quality and reduce the impact of urban stormwater runoff, European countries have been implementing various policies and measures. These include efforts to improve sewage treatment plants, reduce pollution, and conserve aquatic ecosystems. While there have been achievements in some areas, such as bathing water quality and drinking water treatment, other issues such as plastic litter in seas and wetland conservation continue to be a cause for concern.

Sewage and wastewater treatment

The European Union and its Member States have implemented policies and measures to improve water quality, including the Urban Wastewater Treatment (UWWT) Directive, first adopted in 1991. This directive sets out a time plan for the construction of infrastructure for collecting and treating wastewater in urban areas. As a result, the quality of European rivers, lakes, and seas has improved significantly. Over time, the directive has been revised to build on this legacy and address remaining pollution challenges and new urban wastewater management issues.

The latest revision of the UWWT Directive, proposed in October 2022, introduces a quaternary treatment level to tackle micropollutants and microplastics in wastewater. This revision aims to reduce the occurrence of substances of concern in wastewater treatment plant effluents. It also includes requirements for monitoring and new standards to ensure the appropriate collection and treatment of urban wastewater, protecting the environment and human health.

Since 2000, there has been a steady increase in the proportion of the EU population connected to wastewater treatment. By 2022, 81% of the EU population was connected to at least secondary wastewater treatment, which has contributed to improving the quality of freshwater in European surface water bodies.

However, challenges remain, particularly in central and eastern European states, where financial restrictions, outdated infrastructure, and technical and human resource limitations compromise the satisfactory treatment and maintenance of water distribution systems.

Climate change

Firstly, climate change is causing more frequent and severe extreme weather events, such as flooding, rising sea levels, droughts, and wildfires. Flooding and rising sea levels can contaminate water resources with saltwater or faecal matter, as well as damage water infrastructure, such as wells and wastewater treatment facilities. This can lead to the mixing of contaminated water with freshwater sources, further exacerbating water pollution. Droughts and wildfires can reduce water availability and quality, as well as trigger civil unrest and migration.

Secondly, climate change is contributing to the increased demand for water, particularly in agriculture, which is Europe's highest net water consumer. Irrigated agriculture is likely to increase with climate change, putting more pressure on water resources. This is especially true as terrestrial water storage, including soil moisture, has been dropping at a rate of 1 cm per year over the past two decades.

Thirdly, climate change is linked to the degradation of habitats and ecosystems that are crucial for water regulation and supply. For example, glacier melting has significantly contributed to global sea-level rise, with today's sea levels about 20 cm higher than in 1900. This affects the regulation of freshwater resources for people in lowland areas. Additionally, the destruction of vegetation and tree cover reduces groundwater recharge, further increasing water scarcity.

To adapt to these challenges, Europe needs to adopt climate-smart agricultural practices, such as improving soil moisture retention, using drip irrigation, and reusing wastewater. Exploring, protecting, and sustainably using groundwater sources will be essential in ensuring water security for a growing population.

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