Learn Through English

	Natural Science
	Waste Water Treatment

In this activity you are going to learn how waste water is treated before it is sent back to a river or sea. Read about it on this website and then answer the following questions in your worksheet.

A. What are the usual contaminants we can find in waste water?

B. Identify the different parts in the following picture as in the example.

	1st Settling tank
	Solid collector
	Gas collector
	Town sewers	A
	Fertilizer collector
	2nd Settling tank
	Screen
	Bacteria addition
	Water tester
	Aeration tank
	Clean water exit

C. Once the different parts have been identified, complete the whole process of waste water treatment by playing this game.

D. Where do most cities and towns get their drinking water from? What do we do with that water before we can drink it?

E. These three substances are added to water. What do they do?

F. What four materials are used as filters?

G. When waste water has been treated, it goes through a new process to make it drinkable. With the picture help try to reconstruct this process of treating drinking water. Use the clues below. If you still can't manage, try this game.

DIAGRAM	PROCESS	CLUES
	1.	More chlorine is added to kill remaining algae and micro-organisms.
	2.	The water is stirred in a large tank to make the suspended solids clump together, making them easier to remove.
	3.	Before it is sent to our homes water is stored in a tank.
	4.	Chlorine is added to kill micro-organisms.
	5.	The water flows through the filters
	6.	Lime and alum may be added, too.
	7.	The solid clumps are collected from the bottom of a settling tank.

H. Alternative methods are becoming more and more popular nowadays. Name two advantages.

I. When water is not treated correctly some problems may arise. What happened in North Battleford in Canada? What were the consequences? Who was responsible for that?

Activity adapted from Worsley School website.

Back to the top.