Water Pollution

The world is confronted with a global water quality crisis. The continuing growth of population growth and urbanisation, rapid industrialisation, and expanding and intensifying food production are all putting pressure on water resources and increasing the unregulated or illegal discharge of contaminated water within and beyond national borders (CORCORAN et al. 2010).

Water is essential for all aspects of life and the defining feature of our planet. About 97.5% of all water is found in the oceans and of the remaining freshwater only one percent is accessible for extraction and use. Functioning and healthy aquatic ecosystems provide us with a dazzling array of benefits — food, medicines, recreational amenity, shoreline protection, processing our waste, and sequestering carbon (CORCORAN et al. 2010).

In some areas of the world, rivers, lakes and seas have become so polluted that ecosystems and the health of plants, animals, and humans are threatened. Pollution from agriculture, industry and domestic wastewater is making water resources, both surface water and groundwater, increasingly scarce and decreasingly poor in quality (DOPP n.y.).

In recent years, many nations have realised the problem of increasing water pollution. Some of these nations are taking steps to control or clean up the polluted waters ― yet, it remains a problem that is not tackled in many areas of the world.

Water pollution can come from several of different sources. If the pollution comes from a single source, such as an oil spill, it is called point-source pollution. If the pollution comes from many sources, it is called nonpoint-source pollution. Most types of pollution affect the immediate area surrounding the source. Sometimes the pollution may affect the environment hundreds of miles away from the source, such as nuclear waste; this is called transboundary pollution (WATER POLLUTION GUIDE 2008).

Every day, 2 million tons of sewage, industrial and agricultural waste is released into the world’s water. The United Nations estimates that the amount of wastewater produced every year is about 1,500 km³, six times more water than exists in all the rivers of the world (PACIFIC INSTITUTE 2010).

(Adapted from SDWF 2008)

Water pollution can be defined in several ways. Water pollution occurs when nutrients and other materials are released, degrading the quality of the water for other users. Water pollution includes all of the waste materials that cannot be naturally broken down by water. In other words, anything that is added to the water, above and beyond its capacity to break it down, is pollution. Pollution can be caused by nature itself, such as when water flows through soils with high acidity. But much more often, human actions are responsible for the pollutants that enter the water.

(Adapted from CORCORAN et al. 2010)

The way food is produced worldwide uses 70–90% of the available fresh water, returning much of this water to the system with additional nutrients and contaminants. It is a domino effect as downstream agricultural pollution is joined by human and industrial waste. This wastewater is polluting freshwater and coastal ecosystems, threatening food security, access to safe drinking and bathing water and providing a major health and environmental management challenge. Up to 90% of wastewater flows untreated into the densely populated coastal zone contributing to growing marine dead zones. A staggering 80–90% of all wastewater generated in developing countries is discharged directly into surface water bodies.

Contaminated water from inadequate wastewater management provides one the greatest health challenges restricting development and increasing poverty through costs to health care and lost labour productivity. Unregulated discharge of wastewater threats and decreases biological diversity, natural resilience and the capacity of the planet to provide fundamental ecosystem services, impacting both rural and urban populations and affecting sectors from health to industry, agriculture, fisheries and tourism. In all cases, it is the poorest that are the most severely affected.
Wastewater management — or rather the lack of it — has a direct impact on the biological diversity of aquatic ecosystems, disrupting the fundamental integrity of our life support systems, on which a wide range of sectors from urban development to food production and industry depend. It is essential that wastewater management be considered as part of integrated, ecosystem-based management that operates across sectors and borders, freshwater and marine.

(Adapted from CORCORAN et al. 2010)

Wastewater has long been used as a resource in agriculture. The use of contaminated water in agriculture for irrigation and fertilising purposes can be managed through the implementation of various barriers which reduce the risk to both crop viability and human health. Today, an estimated 20 million hectares of land is irrigated using wastewater worldwide, particularly in arid and semiarid regions and urban areas where unpolluted water is a scarce resource. There are clear health advantages related to wastewater use in agriculture, stemming directly from the provision of food (mainly vegetables) to urban populations. It is estimated that 10% of the world’s population relies on food grown with contaminated wastewater.

Recognising wastewater as a resource has a huge positive impact on the outcome of agriculture production and reduces the water pollution by preventing the disposal of contaminated wastewater into water bodies. Reusing wastewater in agriculture can also integrate wastewater produced in industries (see also optimisation of water use in industry or in agriculture). Furthermore, the industrial sector can also reuse its own generated wastewater for various processes within its production and therefore prevent water pollution by releasing untreated wastewater into water bodies. Reusing wastewater has therefore two main advantages: it improves the living conditions of the local population through better food production and reduces the water pollution in these areas (see also recharge and reuse).

(Adapted from CORCORAN et al. 2010)

Under-dimensioned and aged wastewater infrastructure is already overwhelmed, and with predicted population increases and changes in the climate the situation is only going to get worse. Without better infrastructure and management, millions of people will continue to die each year and there will be further losses in biodiversity and ecosystem resilience, undermining prosperity and efforts towards a more sustainable future.

Currently, most of the wastewater infrastructure in many developing countries and fastest growing cities is either non-existent, inadequate or outdated and therefore entirely unable to keep pace with the demands of rising populations. Experience has shown that substantial investments done in the right manner can provide the required returns (see economic issues. However, finding a solution will require not only investment but also carefully integrated national to municipal water and wastewater planning that addresses the entire water chain — drinking water supply (see water sources, production and treatment of wastewater, ecosystem management, agricultural efficiency and urban planning.

Wastewater management has many associated environmental benefits, enabling ecosystems within watersheds and the productive coastal zone to thrive and deliver services on which healthy communities and economies depend. Inadequate management in turn incurs heaving costs, threatening to undermine these ecosystems. However the value of these benefits is often not calculated because they are not determined by the market, due to inadequate property rights, the presence of externalities, and the lack of adequate information. Valuation of these benefits is nevertheless necessary to justify suitable investment policies and financing mechanisms (see also policies and legal framework).

(Adapted from WATER POLLUTION GUIDE 2008)

Besides the global water pollution caused by inadequate wastewater management, there are other factors which contribute to the global water pollution:

• Eutrophication: Eutrophication is when the environment becomes enriched with nutrients through wastewater or fertilisers which are released to water bodies. This can be a problem in marine habitats such as lakes as it can cause algal blooms. Fertilisers are often used in farming, sometimes these fertilisers run-off into nearby water causing an increase in nutrient levels. This causes phytoplankton to grow and reproduce more rapidly, resulting in algal blooms. This bloom of algae disrupts normal ecosystem functioning and causes many problems.
• Industrial Waste: Industry is a huge source of water pollution, it produces pollutants that are extremely harmful to people and the environment. Many industrial facilities use freshwater to carry away waste from the plant and into rivers, lakes and oceans.
• Marine Dumping: Dumping of litter in the sea can cause huge problems to the environment and human beings. A good example is the “Great Pacific Garbage Patch”, also described as the Pacific Trash Vortex. This is a gyre of marine litter in the central North Pacific Ocean. The patch extends over a very wide area, with estimates ranging from an area the size of the state of Texas to one larger than the continental United States. The patch is characterised by exceptionally high concentrations of pelagic plastics, chemical sludge, and other debris that have been trapped by the currents of the North Pacific Gyre. Some of these long-lasting plastics end up in the stomachs of marine birds and animals. These toxin-containing plastic pieces are also eaten by jellyfish, which are then eaten by larger fish. Many of these fish are then consumed by humans, resulting in their ingestion of toxic chemicals (WIKIPEDIA 2010).
• Oil Pollution: Oceans are polluted by oil on a daily basis from oil spills, routine shipping, run-offs and dumping. Oil spills make up about 12% of the oil that enters the ocean. The rest come from shipping travel, drains and dumping. An oil spill from a tanker is a severe problem because there is such a huge quantity of oil being split into one place.
• Radioactive Waste: Nuclear waste is produced from industrial, medical and scientific processes that use radioactive material. Nuclear waste can have detrimental effects on marine habitats.
• Underground Storage Leakages: A tank or piping network that has at least 10 percent of its volume underground is known as an underground storage tank (UST). They often store substances such as petroleum, that are harmful to the surrounding environment should it become contaminated. Many UST’s constructed before 1980 are made from steel pipes that are directly exposed to the environment. Over time the steel corrodes and causes leakages, affecting surrounding soil and groundwater.
• Global Warming: An increase in water temperature can result in the death of many aquatic organisms and disrupt many marine habitats. For example, a rise in water temperatures causes coral bleaching of reefs around the world. This is when the coral expels the microorganisms of which it is dependent on. This can result in great damage to coral reefs and subsequently, all the marine life that depends on it.
• Atmospheric Deposition: Atmospheric deposition is the pollution of water caused by air pollution. In the atmosphere, water particles mix with carbon dioxide sulphur dioxide and nitrogen oxides, this forms a weak acid. Air pollution means that water vapour absorbs more of these gases and becomes even more acidic. When it rains the water is polluted with these gases, this is called acid rain. When acid rain pollutes marine habitats such as rivers and lakes, aquatic life is harmed.
• Noise Pollution: Over the past decades, an increase in water traffic, oil extraction, sonar system etc. have lead an increasing noise pollution of the oceans. Sound travels much faster under water than on air, and thus also much farther. This increasing noise has adverse impacts on aquatic live that are not yet entirely clear but are significant.

(Adapted from KRAEMER et al. 2001)

Political approaches: Ineffective regulatory oversight, institutional failures and lack of political commitment are often mentioned as some of the most significant causes of water pollution problems. Therefore, a critical step towards the protection of water resources is the creation of will and commitment among political parties at all levels, to seriously invest human and financial capital in the protection of freshwater and related ecosystems and to consider the polluter pays principle in all relevant water policy formulation.

Legal Instruments: Legal instruments, so-called command and control strategies have been used widely over the past 20 years and still remain important in several high-income as well as developing countries. The approach of command and control, however, is yielding fewer benefits per unit of expenditure in some industrialised countries, while developing countries often lack the necessary preconditions for implementing pollution control measures (see also invalid link). Even where court orders have sentenced closure of polluting industries, these often have silently reopened for economic and employment reasons. In some cases, the effectiveness of traditional enforcement measures such as inspections and penalties has been successfully strengthened through combination with other instruments such as public disclosure programmes and economic instruments.

Economic Instruments: A shift to economic market based instruments to combat water pollution is being experienced. Water charges are one of the most frequently used economic instruments and should be high enough to effectively induce changes in behaviour and foster preventive measures. It is recommended that such measures should be phased in gradually to take due account of the social and economic implications. An immediate response to high charges is not as easy to achieve in lower income countries as in industrialised ones. On the other hand, the effect of charges set at a fairly low level, as in some European countries in transition, is questionable. In this case, charges are low due to the present low economic status and the state of industry. Water pollution cannot be addressed by price and market-based schemes alone. Experience points to the combination of planning, regulation (e.g. monitoring) and economic instruments (e.g. charges, tradable permits). The existence of direct regulations appears to be a necessary pre-condition for the successful implementation of economic instruments (see also policies and legal framework).

Co-operation: Several examples of co-operation among stakeholders such as bilateral agreements, river commissions, water pollution control through public information and participation and co-operation between private companies and local stakeholders. The involvement of user and community-based organisations, which are expressions of civil society, is also increasingly recognised as a central principle in the protection of water resources. In this context, water user associations and farmer groups need to be properly trained and included in the debate.

Paradigm Shift: Single sector approaches such as wastewater treatment or river basin management are limited in their actions. To save and recycle water, regain resources and to protect aquatic ecosystems, the whole water cycle needs to be taken into account in an integrated, holistic way – linking up reuse-oriented sanitation approaches with IWRM. See SSWM concept.