Water pollution (or aquatic pollution) is the contamination of water bodies, usually as a result of
human activities. Water bodies include for example lakes, rivers, oceans, aquifers and groundwater.
Water pollution results when contaminants are introduced into the natural environment. For example,
releasing inadequately treated wastewater into natural water bodies can lead to degradation of aquatic
ecosystems. In turn, this can lead to public health problems for people living downstream. They may
use the same polluted river water for drinking or bathing or irrigation. Water pollution is the leading
worldwide cause of death and disease, e.g. due to water-borne diseases.
Water pollution can be classified as surface water or groundwater pollution. Marine
pollution and nutrient pollution are subsets of water pollution. Sources of water pollution are
either point sources or non-point sources. Point sources have one identifiable cause of the pollution,
such as a storm drain or a wastewater treatment plant. Non-point sources are more diffuse, such
as agricultural runoff.] Pollution is the result of the cumulative effect over time. All plants and
organisms living in or being exposed to polluted water bodies can be impacted. The effects can
damage individual species and impact the natural biological communities they are part of.
Water pollution occurs when unwanted materials enter in to water, changes the quality of water and
harmful to environment and human health . Water is an important natural resource used for drinking
and other developmental purposes in our lives . Safe drinking water is necessary for human health all
over the world. Being a universal solvent, water is a major source of infection. According to world
health organization (WHO) 80% diseases are water borne. Drinking water in various countries does
not meet WHO standards 3.1% deaths occur due to the unhygienic and poor quality of water.
Discharge of domestic and industrial effluent wastes, leakage from water tanks, marine dumping,
radioactive waste and atmospheric deposition are major causes of water pollution. Heavy metals that
disposed off and industrial waste can accumulate in lakes and river, proving harmful to humans and
animals. Toxins in industrial waste are the major cause of immune suppression, reproductive failure
and acute poisoning. Infectious diseases, like cholera, typhoid fever and other diseases gastroenteritis,
diarrhea, vomiting, skin and kidney problem are spreading through polluted water. Human health is
affected by the direct damage of plants and animal nutrition. Water pollutants are killing sea weeds,
mollusks, marine birds, fishes, crustaceans and other sea organisms that serve as food for human.
Insecticides like DDT concentration is increasing along the food chain. These insecticides are harmful for humans.
Objective of the study :-
The main objective of the project work is role of water in our life. How important it is. Controlling
city pollution by water pollution.
Definition of water pollution :-
Water is typically referred to as polluted when it is impaired by anthropogenic contaminants. Due to
these contaminants it either does not support a human use, such as drinking water, or undergoes a
marked shift in its ability to support its biotic communities, such as fish. Natural phenomena such
as volcanoes, algae blooms, storms, and earthquakes also cause major changes in water quality and
the ecological status of water.
Water pollution is a major global problem. It requires ongoing evaluation and revision of water
resource policy at all levels (international down to individual aquifers and wells). It has been
suggested that water pollution is the leading worldwide cause of death and diseases.] Water pollution
accounted for the deaths of 1.8 million people in 2015.
The organization Global Oceanic Environmental Survey (GOES) consider water pollution as one of
the main environmental problems that can present a danger for the existence of life on earth in the
next decades. One of the main concerns, is that water pollution, heart phytoplankton who produce
70% of oxygen and remove a large part of carbon dioxide on earth. The organization proposes a
number of measures for fixing the situation, but they should be taken in the next 10 years for being
Water pollution in India and China is wide spread. About 90 percent of the water in the cities of
China is polluted.
In addition to the acute problems of water pollution in developing countries, developed countries also
continue to struggle with pollution problems. For example, in a report on water quality in the United
States in 2009, 44 percent of assessed stream miles, 64 percent of assessed lake acres, and 30 percent
of assessed bays and estuarine square miles were classified as polluted.
The causes of water pollution include a wide range of chemicals and pathogens as well as physical
parameters. Contaminants may include organic and inorganic substances. Elevated temperatures can
also lead to polluted water. A common cause of thermal pollution is the use of water as
a coolant by power plants and industrial manufacturers. Elevated water temperatures decrease oxygen
levels, which can kill fish and alter food chain composition, reduce species biodiversity, and foster
invasion by new thermophilic species.
Water pollution is measured by analysing water samples. Physical, chemical and biological tests can
be conducted. Control of water pollution requires appropriate infrastructure and management plans.
The infrastructure may include wastewater treatment plants. Sewage treatment plants and industrial wastewater treatment plants are usually required to protect water bodies from untreated
wastewater. Agricultural wastewater treatment for farms, and erosion control at construction sites can
also help prevent water pollution. Nature-based solutions are another approach to prevent water
pollution.Effective control of urban runoff includes reducing speed and quantity of flow. In the
United States, best management practices for water pollution include approaches to reduce the
quantity of water and improve water quality.
TYPES OF WATER POLLUTION:-
1. SURFACE WATER POLLUTION :-
Surface water pollution includes pollution of rivers, lakes and oceans. A subset of surface water
pollution is marine pollution.
Water pollution from human activity, including oil spills and also presents a problem
for freshwater resources. The largest petroleum spill that has ever occurred in fresh water was caused
by a Royal Dutch Shell tank ship in Magdalena, Argentina, on 15 January 1999, polluting the
environment, drinkable water, plants and animals Chemical contamination of fresh water can also
seriously damage eco-systems.
In industrialized areas rain can be acidic because of dissolved oxides of sulfur and nitrogen formed
from burning of fossil fuels in cars, factories, trains and aircraft and from the atmospheric emissions
of industry. In some cases this acid rain results in pollution of lakes and rivers.
2. GROUNDWATER POLLUTION:-
Groundwater pollution (also called groundwater contamination) occurs when pollutants are
released to the ground and make their way down into groundwater. This type of water pollution can
also occur naturally due to the presence of a minor and unwanted constituent, contaminant or impurity
in the groundwater, in which case it is more likely referred to as contamination rather than pollution.
The pollutant often creates a contaminant plume within an aquifer. Movement of water and dispersion
within the aquifer spreads the pollutant over a wider area. Its advancing boundary, often called a
plume edge, can intersect with groundwater wells or daylight into surface water such as seeps and
springs, making the water supplies unsafe for humans and wildlife. The movement of the plume,
called a plume front, may be analyzed through a hydrological transport model or groundwater model.
Analysis of groundwater pollution may focus on soil characteristics and
site geology, hydrogeology, hydrology, and the nature of the contaminants.
Pollution can occur from on-site sanitation systems, landfills, effluent from wastewater treatment
plants, leaking sewers, petrol filling stations or from over application of fertilizers in agriculture.
Pollution (or contamination) can also occur from naturally occurring contaminants, such
as arsenic or fluoride. Using polluted groundwater causes hazards to public health through poisoningor the spread of disease.Different mechanisms have influence on the transport of pollutants,
e.g. diffusion, adsorption, precipitation, decay, in the groundwater. The interaction of groundwater
contamination with surface waters is analyzed by use of hydrology transport models.
3.CHEMICAL POLLUTION :-
dustrial and agricultural work involves the use of many different chemicals that can run-off into water
and pollute it.Metals and solvents from industrial work can pollute rivers and lakes. These are
poisonous to many forms of aquatic life and may slow their development, make them infertile or even
result in death.Pesticides are used in farming to control weeds, insects and fungi. Run-offs of these
pesticides can cause water pollution and poison aquatic life. Subsequently, birds, humans and other
animals may be poisoned if they eat infected fish.Petroleum is another form of chemical pollutant that
usually contaminates water through oil spills when a ship ruptures. Oil spills usually have only a
localised affect on wildlife but can spread for miles. The oil can cause the death of many fish and
stick to the feathers of seabirds causing them to lose the ability to fly.
ne common path of entry by contaminants to the sea are rivers. An example is directly discharging
sewage and industrial waste into the ocean. Pollution such as this occurs particularly in developing
nations. In fact, the 10 largest emitters of oceanic plastic pollution worldwide are, from the most to
the least, China, Indonesia, Philippines, Vietnam, Sri Lanka, Thailand, Egypt, Malaysia, Nigeria, and
Bangladesh, largely through the rivers Yangtze, Indus, Yellow, Hai, Nile, Ganges, Pearl, Amur,
Niger, and the Mekong, and accounting for “90 percent of all the plastic that reaches the world’s
Large gyres (vortexes) in the oceans trap floating plastic debris. Plastic debris can absorb toxic
chemicals from ocean pollution, potentially poisoning any creature that eats it. Many of these longlasting pieces end up in the stomachs of marine birds and animals. This results in obstruction of
digestive pathways, which leads to reduced appetite or even starvation.
There are a variety of secondary effects stemming not from the original pollutant, but a derivative
condition. An example is silt-bearing surface runoff, which can inhibit the penetration of sunlight
through the water column, hampering photosynthesis in aquatic plants.
IMPACT IN HUMAN HEALTH :-
There is a greater association between pollution and health problem. Disease causing
microorganisms are known as pathogens and these pathogens are spreading disease
directly among humans. Some pathogens are worldwide some are found in well-defined
area]. Many water borne diseases are spreading man to man Heavy rainfall and floods are
related to extreme weather and creating different diseases for developed and developing
countries [10% of the population depends on food and vegetables that are grown in
contaminated water [Many waterborne infectious diseases are linked with fecal pollution of
water sources and results in fecal-oral route of infection]. Health risk associated with polluted
water includes different diseases such as respiratory disease, cancer, diarrheal disease,
neurological disorder and cardiovascular disease Nitrogenous chemicals are responsible for
cancer and blue baby syndrom]. Mortality rate due to cancer is higher in rural areas than
urban areas because urban inhabitants use treated water for drinking while rural people
don’t have facility of treated water and use unprocessed water. Poor people are at greater
risk of disease due to improper sanitation, hygiene and water supply . Contaminated water
has large negative effects in those women who are exposed to chemicals during pregnancy;
it leads to the increased rate of low birth weight as a result fetal health is affected
Poor quality water destroys the crop production and infects our food which is hazardous for
aquatic life and human life [Pollutants disturb the food chain and heavy metals, especially
iron affects the respiratory system of fishes. An iron clog in to fish gills and it is lethal to
fishes, when these fishes are eaten by human leads to the major health issue Metal
contaminated water leads to hair loss, liver cirrhosis, renal failure and neural disorder.
Bacterial diseases :-
Untreated drinking water and fecal contamination of water is the major cause of
diarrhea. Campylobacter jejuni spread diarrhea 4% to 15% worldwide. Fever, abdominal
pain, nausea, headache are major symptoms of diarrhea. Good hygienic practices and use
of antibiotics can prevent this disease. Disease cholera is caused by the contaminated
water. Vibrio Cholerae is responsible for this disease. This bacterium produces toxins in
digestive tracts. The symptoms of this disease are watery diarrhea, nausea, vomiting and
watery diarrhea leads to dehydration and renal failure. Anti- microbial treatment is used to
get rid of this disease.
Shigellosis is a bacterial disease caused by Shigella bacteria. It affects the digestive tract of
humans and damages the intestinal lining. Watery or bloody diarrhea, abdominal cramps,
vomiting and nausea are symptoms and it can be cured with antibiotics and good hygienic
practice. Salmonellosis infects the intestinal tract. Salmonella bacteria are found in
contaminated water and it results in inflammation of intestine and often death occurs.
Antibiotics are prescribed for this disease.
Viral diseases :-
Hepatitis is a viral disease caused by contaminated water and infects the liver. Jaundice,
loss of appetite, fatigue, discomfort and high fever are symptoms of hepatitis. If it persists for
a long time it may be fatal and results in death. Vaccine is available for hepatitis and by
adopting good hygienic practice; one can get rid of this disease Encephalitis is inflammatory
disease spread by bite of infected mosquitoes. Culex mosquito lays their eggs in
contaminated water. Most people don’t show any symptoms but some symptoms are headache, high fever, muscle stiffness, convulsions however in severe cases coma and paralysis
results. No vaccine is available for this disease
Poliomyelitis virus is responsible for poliomyelitis. Sore throat, fever, nausea, constipation and
diarrhea and sometimes paralysis are symptoms of poliomyelitis. Vaccine is available for this disease
Gastroenteritis is caused by different viruses including rotaviruses, adenoviruses, calciviruses
and Norwalk virus. Symptoms of gastroenteritis are vomiting, headache and fever. Symptoms appear
1 to 2 days after infecting. Sickness can be dangerous among infants, young children and disabled.
Parasitic diseases :-
Cryptosporidiosis is a parasitic disease caused by the cryptosporidium parvum. It is worldwide
disease and symptoms are diarrhea, loose or watery bowls, stomach cramps and upset stomach
. Cryptosporidium is resistant to disinfection and affects immune system and it is the cause of
diarrhoea and vomiting in humans Galloping amoeba is caused by the Entamoeba histolytica and
affects stomach lining. This parasite undergoes cyst and non-cyst form. Infection occurs when cyst
found in contaminated water and it is swallowed. Symptoms are fever, chills and watery diarrhea
According to WHO, diarrheal case jootes are about 4 billion and results in 2.2 million deathsGiardiasis is
caused by Giardia lamblia. Cells of intestinal lining may become injure. Giardia is resistant to wintry
temperature and disinfectant. Sometimes it is known as travelers’ disease. People suffering from
giardiasis have symptoms bloating, excess gas, watery diarrhea and weight loss .