Water and People
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Water is the most important substance on the planet. Life could
not exist without it. There are approximately 1 .4 billion trillion
liters of water on Earth and Earth is the only planet in the solar
systam where large VCilt:lmes of water are found on the surface in
liquid form. However, water is not evenly distributed throughout
Water's unique properties make it an unusual
substance. It hal) no taste or odor, it is less
dense in its solid form than in its liquid form
(allowing ice to float). and has an extremely
high boiling pofnt compared to other similar
molecules (such as H2 S). It is polar and so
able to dissolve ionic solids and ·conduct
electricity. It also has an extremely high
surface tension caused by forming strong
bonds between water molecules.
ttie globe; deserts receive very little rainfall whereas other plal(:es
experience large volumes of seasonal or daily. rainfall. DesPite
the enormous amount of water on this planet, wasteful usage
and poor management of treatment and supply has reduced the
amount of fresh water that is available to much of humanity.
The human body is nearly 70% water and
to keep it healthy and functioning correctly
health · authorities recommend drinking
between 1.8 and 2 liters of water per day. In
some countries, access even to this small
amount is difficult. In some areas people ma,y
use just 15 liters of water per day for all· of
their domestic uses including drinking water
(compared to over 570 liters per person per
day in the United States).
Nearly half of the water supplied by municipal
water systems· in the US is used to flush
toilets and water lawns, and another 20-35%
is lost through leakages. Treatment of waste
water places major demands on cities yet
there are few incentives-to reduce water use
and recycle. Providing a reliable clean water
remains a major public health issue in many
poorer regions of.the world. .
Average Domestic Water Use
700
600
.------,---~-~---~------~--.
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500
o_
~ 400
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o_
(ii
300
o_
2i"'
200
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100
0
Potable water (water suitable to drink) is a rare commodity in large parts
of the world. Access to potable water is limited by the availability of suitable
water resource's (e.g. rivers), its ease of distribution, and level of water
treatment (water. borne diseases and dissolvedloxins need to be removed).
Once it is treated, the distribution and storage of water becomes important. In
many countries, distribution of water is difficult and storage of large amounts
Is almost impossible.
1.
2.
3.
4.
Industrialized countries tend to use the most amount of water,
with the United States being one of the largest domestic users.
The amount of water used by people in domestic situations
depends upon the efficiency of the water use, its cost to the
user (higher supply prices usually mean lower use), and the
amount of water available for use.
Describe some of the properties of water.
Explain why water is so if!!portant in living organisms.
Describe the factors that Hmit water supply to some countries.
Explain one way in which to improve efficiency of water use in each of the
domestic situations:
a. Irrigation:
b. Drinking supply:
c. Sanitation:
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5. Analyze why water is a common source of conflict.
For questions 6- 7 write the question and. correct answer:
6. Identify which of the following considerations below are important in effective
water management:.
i.
Mismanagement of water can lead to large volumes being wasted
. either at the source or en-route to the user.
II.
Water is mostly used near its source.
Ill.
Removal of too much water from a body of water can severely
disrupt its natural systems .
.A. .I and II
B. II and Ill
C. I and Ill
D. I, II, and Ill
7. The water on Earth is:
A. Evenly distributed about the globe
B. Effectively finite in volume
C. Mostly freshwater
D. Easily accessible to all people
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