Water Storage Systems

Sujet du devoir

Lisez le texte suivant et répondez aux questions.

This is the VOA* Special English Development Report.
Each year, millions of people in Bangladesh drink ground water that has been polluted by
naturally high levels of arsenic poison. Finding safe drinking water in that country can be a
problem. However, International Development Enterprises has a low-cost answer. This nongovernmental
organization has developed technology to harvest rainwater.
People around the world have been harvesting rainwater for centuries. It is a safe, dependable
source of drinking water. Unlike ground water, rainwater contains no minerals or salts
and is free of chemical treatments. Best of all, it is free.
The rainwater harvesting system created by International Development Enterprises uses
pipes to collect water from the tops of buildings. The pipes stretch from the buildings to a
two-meter tall storage tank made of metal. At the top of the tank is a so-called “first-flush”
device made of wire screen. This barrier prevents dirt and leaves in the water from falling
inside the tank.
A fitted cover sits over the “first-flush” device. It protects the water inside the tank from evaporating.
The cover also prevents mosquito insects from laying eggs in the water.
Inside the tank is a low-cost plastic bag that collects the water. The bag sits inside another
plastic bag similar to those used to hold grains. The two bags are supported inside the metal
12 Évaluation 2 – AN21-10
tank. All total, the water storage system can hold up to three-thousand-five-hundred liters of
water. International Development Enterprises says the inner bags may need to be replaced
every two to three years. However, if the bags are not damaged by sunlight, they could last
even longer.
International Development Enterprises says the water harvesting system should be built on
a raised structure to prevent insects from eating into it at the bottom. The total cost to build
this rainwater harvesting system is about forty dollars. However, International Development
Enterprises expects the price to drop over time. The group says one tank can provide a family
of five with enough rainwater to survive a five-month dry season. International Development
Enterprises has more information at its Web site, www.ideorg.org.
This VOA Special English Development Report was written by Jill Moss.
*VOA : Voice of America
How to Do Things in VOA Special English

7. List 4 advantages of using the water mentioned in the text. (2 pts)

8. List 4 disadvantages of using the water mentioned in the text. (2 pts)

9. Fill in the blanks by words from the text. (2 pts)

The water falls on ………………………………………………… . Then, thanks to a system of ……...............
it is …………………….. and finally ends up in ……………………... .

10. RIGHT or WRONG? Justify your answer by quoting [citer] the text. (6 pts)

a) In the types of countries mentioned in the text it is preferable to drink ground water.
b) The system is cheap.
c) The tanks are very small.
d) The tanks need to be protected.
e) The “first-flush” device works as a filter.
f) The system may provide quite a lot of water.

11. Name the different elements of the system. (3 pts)
12. Give two reasons why the maintenance of the system will be cheap. (2 pts) 

Où j'en suis dans mon devoir

J'ai déjà effectué une partie du devoir en revanche, je ne parviens pas à répondre à la question 8, 9 et 11. J'ai cherché mais en vain. Si vous pouviez m'aidez se serait vraiment sympa de votre part.
P.S : Je suis censé l'avoir fini fin de la semaine.