3. INTRODUCTION
Water pollution is the contamination of water bodies, usually as a
result of human activities.
Water bodies includes 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.
4. SOME FACTS ABOUT WATER
• 68.7% of the fresh water on Earth is trapped in glaciers.
• 70% of the human brain is water.
• A swimming pool naturally loses about 1,000 gallons (3,785
liters) a month to evaporation.
• Two-thirds of the world’s population is projected to face
water scarcity by 2025, according to the United Nations.
• The average pool takes 22,000 gallons of water to fill.
• Hot water can freeze faster than cold water under some
conditions (commonly known as the Mpemba effect).
5. TYPES OF WATER POLLUTION
1) Chemical pollution:
It is the most common type of water pollution. Chemicals can
infiltrate both underground water sources and those sitting on the
Earth’s surface. As an integral component of the agricultural
industry, it’s unsurprising that much of chemical contamination
comes from the pesticides and fungicides used in farming, but
metals and solvents from industrial sites are also leading
contributors.
6. 2) Groundwater pollution:
Agriculture is a key source of water pollution, especially for
groundwater. Fertilisers and pesticides applied to crops can seep
into the ground and contaminate underwater rivers and
waterbeds, thus compromising the quality of wells, boreholes and
other places from which groundwater is extracted for human use.
3) Microbiological pollution:
Microbiological pollution is a naturally occurring form of water
contamination. Micro-organisms such as bacteria, protozoa and
viruses can infiltrate water supplies, causing diseases such as
bilharzia and cholera. Humans are most susceptible to this kind
of pollution in places where adequate water treatment systems
are not yet in place.
7. 4) Nutrient pollution:
While they’re vital for underwater flora and fauna to flourish, an excess of
nutrients can upset the delicate imbalance of water-based ecosystems. Fertilisers
contain a high concentration of nutrients which, if they contaminate rivers, lakes
and coastal areas, can cause algal blooming that can block out sunlight and inhibit
the growth of other organisms.
5) Oxygen-depletion pollution:
Another consequence of algal blooms is their consumption of oxygen supplies. This
means that those species which depend upon oxygen to survive are killed off, while
anaerobic ones thrive. Some anaerobic microorganisms are capable of producing
ammonia, sulphides and other harmful toxins, which can make the water even
more dangerous to animals (and humans, too).
8. CAUSES OF WATER POLLUTION
1. Sewage And Waste Water: Sewage, garbage and liquid waste of
households, agricultural lands and factories are discharged into lakes
and rivers. These wastes contain harmful chemicals and toxins which
make the water poisonous for aquatic animals and plants.
2. Dumping: Dumping of solid wastes and litters in water bodies causes
huge problems. Litters include glass, plastic, aluminum, styrofoam
etc. Different things take different amount of time to degrade in water.
They affect aquatic plants and animals.
3. Industrial Waste: Industrial waste contains pollutants like asbestos,
lead, mercury and petrochemicals which are extremely harmful to
both people and environment. Industrial waste is discharged into
lakes and rivers by using fresh water making the water contaminated.
9. 4. Oil Pollution: Sea water gets polluted due to oil spilled from ships and
tankers while traveling. The spilled oil does not dissolve in water and forms
a thick sludge polluting the water.
5. Acid Rain: Acid rain is pollution of water caused by air pollution. When
the acidic particles caused by air pollution in the atmosphere mix with water
vapor, it results in acid rain.
6. Global Warming: Due to global warming, there is an increase in water
temperature. This increase in temperature results in death of aquatic plants
and animals. This also results in bleaching of coral reefs in water.
7. Eutrophication: Eutrophication is an increased level of nutrients in water
bodies. This results in bloom of algae in water. It also depletes the oxygen in
water, which negatively affects fish and other aquatic animal population.
10. EFFECTS OF WATER POLLUTION
Pollution of water affects both humans and aquatic life. Most water
sources close to cities and urban centres are polluted by garbage and
dumping of chemicals, legally or illegally.
Some of the common as well as adverse effects of polluting water bodies
are:-
1. EFFECTS ON HUMAN BEINGS
2. DEATH OF AQUATIC LIFE
3. FOOD CHAIN DISRUPTION
4. DESTRUCTION OF ECOSYSTEMS
11. 1. EFFECTS ON HUMAN BEINGS:
• Life is a cycle, and humanity’s irresponsible behaviour often comes back to
haunt it. Adding contaminants to water bodies has affected the human family in
several ways. According to WHO report, In 2019, it stated that 785 million
people lack access to essential drinking water.
• One of the main effects of this is diseases. World Health Organisation notes that
there are about 120,000 cholera-related deaths annually. Also, the Fukushima
tragedy, for example, increased the prevalence of thyroid cancer in exposed
infants by 70%.
2. DEATH OF AQUATIC LIFE:
• Animals and plants that depend on water for life are the most affected by
polluted water. Statistics from the Centre for Biological Diversity on the effects of
the Deep Horizon spill provides a useful glimpse of the impact of pollution on
aquatic life. In the report, the 2010 spill on the Gulf of Mexico harmed over
82,000 birds, 25,900 marine animals, 6165 sea turtles, and an unknown number
of fish and invertebrates.
12. 3. FOOD CHAIN DISRUPTION:
Pollution disrupts the food chain by moving the toxins from one
level in the chain to higher levels. In some cases, pollution can
wipe out an entire part of the food chain. Such affect the other
organisms by either causing excessive growth, in case the
predator dies or death (if it wipes out the prey).
4. DESTRUCTION OF ECOSYSTEMS:
The introduction or elimination of certain microorganisms
distorts the ecosystem. Nutrient pollution, for example, leads to
an increase in algae, which depletes the water of oxygen,
thereby leading to the death of fish and other aquatic life.
13. TREATMENT OF POLLUTED WATER
• Industrial Treatment: The raw sewage is needed to be treated correctly in a water
treatment plant before it can be safely released into the environment. To reduce the amount
and toxicity of waste, it is passed through a number of chambers and chemical processes in
water treatment plant.
• Denitrification: Conversion of nitrates in gas is called Denitrification. It is an ecological
approach to prevent leaching of nitrates in soil. It stops ground water from getting
contaminated.
• Ozone Waste Water Treatment: Ozone waste water treatment method is becoming
very popular. In this method, the pollutants in water are broken down by an ozone generator.
Ozone oxidizes bacteria, molds, organic material and other pollutants in water.
• Septic Tanks: Septic tanks are used to treat sewage at the place of location instead of
treating it in any plant or sewage system. This system is used at the individual building
level.The sewage is separated into solid and liquid components and treated separately.
14. CONCLUSION
• Water pollution is a global issue and world community is facing
worst results of polluted water. Major sources of water pollution
are discharge of domestic and agriculture wastes, population
growth, excessive use of pesticides and fertilizers and
urbanization.
• Bacterial, viral and parasitic diseases are spreading through
polluted water and affecting human health. It is recommended
that there should be proper waste disposal system and waste
should be treated before entering in to river. Educational and
awareness programs should be organized to control the
pollution.
