WATER POLLUTION
- Water pollution is the contamination of water bodies (e.g. lakes, rivers, oceans, aquifers, and groundwater).
- Water pollution occurs when pollutants are discharged directly or indirectly into water bodies without adequate treatment to remove harmful compounds.
- Water pollution affects plants and organisms living in these bodies of water.
- In almost all cases the effect is damaging not only to individual species and populations but also to the natural biological communities.
Polluted Water comes from
- Domestic sewage.
- Industrial wastewater.
- Agricultural wastewater.
- Construction site stormwater.
- Urban runoff (stormwater).
- Petroleum hydrocarbons
- Plastics
- Pesticides
- Heavy metals
- Sewage
- Radioactive waste
- Thermal effluents Water Pollutant
- Detergents
- Chloroform
- Food processing waste, (fats and grease)
- Insecticides and herbicides.
- Petroleum hydrocarbons, (gasoline, diesel fuel, jet fuels, and fuel oil).
- Lubricants (motor oil).
- From stormwater runoff.
Preventing Water Pollution
- Conserve water by turning off the tap.
- Mind what you throw down your sink or toilet.
- Don’t throw paints and oils in water channels.
- Use environment-friendly household products, such as washing powder, household cleaning agents, etc.
- Take great care, not to overuse pesticides and fertilizers.
- Don’t throw litter into rivers, lakes or oceans.
- Help clean up any litter you see on beaches or in rivers and lakes, make sure it is safe to collect the litter and put it in a nearby dustbin.
Treating Polluted Water
- Suspended, solid particles and an inorganic material can be removed by the use of filters.
- Use of biological filters and processes can naturally degrade the organic waste material.
- After the above two steps, chemical additives are supplied to get rid of any left-over impurities.
Sewage Pollution
Domestic households, industrial and agricultural practices produce wastewater that can cause pollution of many lakes and rivers.
- Sewage is the term used for wastewater that often contains feces, urine, and laundry waste.
- There are billions of people on Earth, so treating sewage is a big priority.
- Sewage disposal is a major problem in developing countries as many people in these areas don’t have access to sanitary conditions and clean water.
- Untreated sewage water in such areas can contaminate the environment and cause diseases such as diarrhea.
- Sewage in developed countries is carried away from the home quickly and hygienically through sewage pipes.
- Sewage is treated in water treatment plants and the waste is often disposed into the sea.
- Sewage is mainly biodegradable and most of it is broken down in the environment.
- In developed countries, sewage often causes problems when people flush chemical and pharmaceutical substances down the toilet. When people are ill, sewage often carries harmful viruses and bacteria into the environment causing health problems.
Methods of Sewage Disposal
Sewage disposal is broadly classified into the following types:
Methods of Sewage Disposal
Dilution – Raw sewage or partly treated sewage is thrown into natural water bodies such as sea, river, lake, marshy land, etc. Self-purification is the mechanism in this process, which is helped by the following factors:
- Dilution of contaminants by dispersion in flowing water.
- Sedimentation of particles to the water bed.
- Oxidation of organic matter by dissolved oxygen in the water.
- Sunlight, which kills harmful bacteria.
- Microbial organisms consuming the solid organic matter in sewage.