What is water pollution?

It is the contamination of water

bodies “lakes, rivers, oceans
and ground water.
Water pollution affect the
species who depend on
water
How can this happen?
Water pollution
happen when
pollutants are
discharged into
water without
adequate
 What are the main
causes of Water
pollution?
 Industrialization
Rapid human population
growth
How can we know how to
prevent water pollution?
In order to know that we
have to understand what the
pollutants are and their
types & origins.
What are the types of
water pollution?
What are the types of
water pollutants?
• Pathogens “ disease causing
organisms , come from
sewage, farms …etc”
•Organic matter “animal &plants
remains, sewage…etc”
 •Organic chemicals
“fertilizers , pesticides,
detergents, plastic, oil”
•Inorganic chemicals “acids ,
bases , salts….etc”
•Heavy metals “Mercury, lead,
cadmium, arsenic. From
households, mining…etc”
•Physical agents “heat that come
from industrial process &
suspended solids that come
from soil erosion”
 Wastewater
• It is water that contain waste
from homes and industry.
• It flows through pipes to places
where it is filtered to make it
clean enough to return to a
river, lake …etc.
 However there happen to be
some toxins that aren’t removed
by the standard treatment
 Those toxins forms a
sewage sludge
• It is the solid
material that
remain after the
treatment.
If so then how to treat
the wastewater
• However It is expensive to
dispose of sludge as you have to
burn it then bury the ashes in a
secure landfill.
• However it can be of use:
1. It can be combined with clay to
form bricks
2. It ,if the toxicity is reduced to safe
levels, can be used as a fertilizer.
 Eutrophication
• Nutrients in water come from organic
matter that is broken down to mineral
nutrients by decomposers
• The organic matter builds up in a
water body and during the process
of decomposing consumes
oxygen and by time the oxygen is
deleted from the water body
• The lakes gets naturally eutrophic
by time
Artificial Eutrophication
It is the Eutrophication caused by
humans due to adding materials that
accelerate the process
 How can thermal pollution
happen?
It can happen when
power plants and other
industries use water in
their cooling system
then discharge warm
water into a lake
or a river
 We have said before that
organisms are adapted to a
certain rang of temperature
and when that temperature
decreases or increases the
organism die
 Thermal pollution
It is the harmful increase in water
temperature in streams, rivers, lakes,
or occasionally, coastal ocean waters
that causes fish death also it
decreases the amount of
oxygen.
Groundwater Pollution
Unfortunately nowadays the
ground water is polluted
This pollution happen when
pollutants sneak out from the
earth’s surface to the aquifer.
How can ground water get
polluted?
It is almost impossible to clean
up ground water as:
Even if you stopped pollution there
would be still polluted ground
water
The process that an aquifer take to
recycle water can take hundreds or
thousands of years.
 It is difficult to
decontaminate as it is
dispersed throughout large
areas of rock and sand.
Even if we pumped out the
water in an aquifer and
replaced it with clean water ,
Ocean Pollution
Pollutants are dumped in the ocean:
Ships can legally dump wastewater and
garbage in some parts of the ocean.
85% of ocean pollution(oil ,toxic wastes
, and medical wastes) comes from
activities on land.
Coastal ecosystems ( coral reefs,
estuaries, and coastal marshes) are
the most affected by pollution.
Ocean water is also polluted
accidental oil spills
Oil spills account only about
5%of oil pollution in oceans.
Every year million gallons of oil
enter the oceans from unknown
sources on land.
Limiting these unknown sources
of oil pollution would contribute a
lot of keeping the oceans clean.
 Water pollution&
Ecosystem
• Water pollution can cause
immediate damage to an
ecosystem .
• Many pollutants accumulate in
the environment because they
don’t decompose quickly.
• As pollutant levels increase, an
• Biomagnification is the build
up of pollutants at higher levels
of food chain
• It has alarming consequences
for organisms at the top of the
food chain