What are the different types of pollution? What are the main sources of water pollution? What are the causes and consequences? A complete course to find out everything you need to know about water pollution!
Definition of water pollution
Water is essential to life. To meet the needs of mankind and the environment, water must be of good quality. If water quality is altered, the entire balance is threatened.
Europe defines good quality water by its good ecological and chemical status. Good ecological status means that the environment is functioning properly, and is assessed in terms of aquatic diversity (fauna and flora). Good chemical status, on the other hand, takes into account the parameters of pollution by toxic substances.
There are three main types of water pollution:
Bacteriological pollution:this is caused by bacteria, mainly from the discharge of (untreated) wastewater containing faecal matter and organic waste*.
Chemical pollution : this generally comes from waste water containing cleaning products, hydrocarbons and heavy metals
Aquatic waste pollution:defined as “any manufactured material or object used for the benefit of mankind that is directly or indirectly discarded or abandoned in aquatic environments”
There are many possible sources of pollution, but there are four main ones.
The different sources of pollution
Domestic pollution
This is generally linked to waste water discharges, which can be of two types:
– Wastewater from everyday water use (toilets, cooking, showers, etc.) contains organic waste or faecal matter. Homes that are poorly or not at all connected to the public sewerage system can cause bacteriological pollution of the water.
– The household products we use contain chemical pollutants that are harmful to the environment. When mixed with water, they end up in our drains or in the environment, causing chemical pollution. The residues of these products, which are difficult to treat by sewage systems, add chemical substances to watercourses.
Industrial pollution
Industry generates different types of pollution depending on the sector of activity. Paper mills, for example, use large volumes of chemicals in their manufacturing processes. Despite regulations requiring their wastewater to be treated, some substances remain difficult to eliminate and end up in the environment.
Agri-food activities (canneries, cooperatives, etc.) process large volumes of organic matter, which enriches the environment with nutrients* and contributes to eutrophication*.
Agricultural pollution
Pesticides and fertilisers cause chemical pollution. The massive use of natural fertilisers, such as manure*, can be a source of bacteriological pollution. These substances infiltrate or run off through the water cycle, polluting aquatic environments.
Pollution linked to maritime transport
Maritime transport can be the source of chemical pollution. This is often caused by the deliberate or unintentional discharge of hydrocarbons directly into the ocean. Oil spills are the most striking example.
The consequences of water pollution
Consequences for the aquatic environment
Water quality has a direct impact on the state of aquatic environments, both fauna and flora. The proper functioning of ecosystems* depends on the quality of the water in which they are found, and the balance of aquatic environments is very fragile
The presence of fertilisers (of agricultural origin) in the ocean has the same effect on certain aquatic plants as on land plants. This is what is happening in Brittany with the proliferation of green algae invading the beaches. This phenomenon is also known as the green tide.
The massive use of synthetic hormones both in agriculture (livestock farming) and in everyday life (medicines) has resulted in the feminisation of certain aquatic species (fish, reptiles, etc.).
Consequences for human health and activities
Water quality has an impact on human health and activities.
Bacteriological pollution can cause illness (ear infections, gastroenteritis, skin rashes, etc.) in bathers and water sports enthusiasts. This pollution is detected by analysis of two intestinal bacteria: Escherichia coli and enterococci. The health risks associated with chemical pollution are less well known and therefore more difficult to detect.
Consequences for the economy
Pollution can have serious consequences for economic activities. Oyster farming plays a major role on the Aquitaine coast. The sale of oysters is regulated and their contamination by polluted water can, for example, lead to a one-off ban on their sale. The quality of coastal waters is essential for seaside resorts. Any beach closure due to pollution will result in a drop in the number of beach-goers, and therefore a significant economic impact.
Whatever the type of pollution, the impoverishment of a natural environment reduces its attractiveness. So it’s in everyone’s interest to preserve it.
Solutions to combat water pollution
Public services have introduced a number of standards to combat water pollution.
Combating domestic pollution
To prevent wastewater residues from ending up in our waterways, several types of action are being taken at wastewater treatment plants:
– bringing facilities up to standard (rebuilding or modernising)
– improving water treatment methods
Combating industrial pollution
Standards exist at national level, penalising operators who discharge their wastewater directly into lakes or rivers. In addition, since 2006 they have been required to declare their activities in a European register. National standards may be supplemented by local regulations and inspections.
Combating agricultural pollution
In order to prevent the infiltration of chemical substances present in pesticides and fertilisers, farmers are obliged to plant vegetation on plots of land close to watercourses.this practice creates a natural vegetation filter, reducing the amount of pollutants entering watercourses.
On an individual scale
It is also possible to limit water pollution on an individual scale. When you have a septic tank*, it’s important that it’s properly maintained to prevent wastewater seeping into the ground.pollution from cleaning products can also be reduced. In fact, using natural household products and cosmetics that are more respectful of the environment helps to reduce environmental impact. Many labels have now been introduced (Ecocert, European Ecolabel, Nature et progrès, etc.), making it easier to identify these products.
Glossary
Organic waste: Wasteof animal or plant origin.
Ecosystem: System formed by an environment and all the species that live, feed and reproduce there (Larousse)
Eutrophication: A naturalform ofpollution of certain aquatic ecosystems that occurs when the environment receives too much nutrients that can be absorbed by algae, causing them to proliferate.
Septic tank: Tank designed to receive waste water from a dwelling. It consists of a tank in which solid matter settles and liquefies through fermentation. (pro septic tank)
Manure: More or less fermented mixture of animal bedding and excrement, used as an organic fertiliser (Larousse)
Nutrient: Organic or mineral substance that can be directly assimilated without undergoing the degradation processes of digestion. (Larousse)
Phytosanitary products: Products used to protect or treat plants.
Further information
What is water pollution?
Water pollution is considered to be a deterioration in the “good quality of water” that can make its use or consumption harmful to humans and/or aquatic life. Europe defines good quality water by its good ecological and chemical status. This can apply to surface water, rivers and bodies of water, as well as groundwater.
– Industrial pollution from chemicals and organic matter produced by industrial activity
– Agricultural pollution, from the pesticides and fertilisers used
– Domestic pollution, often linked to wastewater discharges
– Accidental, involuntary and one-off pollution
– Pollution linked to maritime transport, with hydrocarbons discharged directly into the oceans.
There are three types of water pollution:
– Bacteriological pollution, caused mainly by bacteria present in wastewater discharges (faecal matter, organic waste)
– Chemical pollution from wastewater containing chemicals (hydrocarbons, heavy metals)
– Pollution from aquatic waste.
There are also :
– Point source pollution, easily and precisely localised
– Diffuse pollution, caused by several pollutants, not very visible and whose cause is difficult to find
Water pollution has three main consequences:
– Ecological, because it degrades the marine environment and even causes the disappearance of certain aquatic species
– Health, as it causes illness when polluted water is ingested or comes into contact with the skin
– Economic, because it reduces the marine resources needed for human activities.
– Pollution by aquatic waste is visible to the naked eye, in the water or on the banks of waterways.
– Bacteriological pollution is observed when there is a high quantity of bacteria present in faecal matter.
– Chemical pollution is assessed by the acidity of the water, as the pH reveals the chemical species present.
Individual and collective action can reduce water pollution. Each individual can act to reduce the amount of waste they produce. National and international plans and laws are then important in limiting pollution. In France, for example, plant protection products (pesticides, fungicides, herbicides) are banned in public places.
