How much Water?
Original lesson entitled “It’s a Small World” by the Children’s Water Education Council of
Canada
http://www.cwec.ca/
Modified for PULSE by Rachel Hughes
Time:
1 class period
Preparation
30 minutes
Time:
Materials: Global water distribution facts
Any material that would represent water
consumption (i.e. Jelly beans, cotton balls, Lego
pieces, bingo chips, etc.)
Clear plastic gallon milk jugs and 2 Liter soda bottles
Water bill
Homework Assignment
Abstract
Students investigate the amount of water available in different countries around the world and
compare it to their daily water use. Groups are given a limited water supply with which they must
perform daily functions. Students explore how unequal distribution of water can cause challenges
that they must overcome to survive and also the need to protect and conserve fresh water
supplies.
Objectives
Students will be able to:
1. Discuss the availability of drinking water around the world and the impact of that
availability on individuals, families and communities.
National Science Education Standards:
CONTENT STANDARD F - Science in Personal and Social Perspectives
NATURAL RESOURCES
* Human populations use resources in the environment in order to maintain and improve their
existence. Natural resources have been and will continue to be used to maintain human
populations.
* The earth does not have infinite resources; increasing human consumption places severe
stress on the natural processes that renew some resources, and it depletes those resources that
cannot be renewed.
* Humans use many natural systems as resources. Natural systems have the capacity to reuse
waste, but that capacity is limited. Natural systems can change to an extent that exceeds the
limits of organisms to adapt naturally or humans to adapt technologically.
ENVIRONMENTAL QUALITY
* Natural ecosystems provide an array of basic processes that affect humans. Those
processes include maintenance of the quality of the atmosphere, generation of soils, control of
the hydrologic cycle, disposal of wastes, and recycling of nutrients. Humans are changing many
of these basic processes, and the changes may be detrimental to humans. [See Content
Standard C (grades 9-12)]
* Materials from human societies affect both physical and chemical cycles of the earth.
* Many factors influence environmental quality. Factors that students might investigate include
population growth, resource use, population distribution, over consumption, the capacity of
technology to solve problems, poverty, the role of economic, political, and religious views, and
different ways humans view the earth.
Teacher Background
The United Nations High Commission for Refugees estimates that an average human needs a
minimum of 30 liters of water a day – 5 liters (approximately 1.3 gallons) for drinking and cooking,
plus 25 liters (approximately 7 gallons) or more to keep clean. The average citizen of the United
States uses about 425 liters (approximately 112 gallons). Canadians average about 340 liters of
water per day. Europeans use about 140 liters per day. In Africa, the average person uses 3 liters
per day. Note that these figures do not include other water uses or technologies that use water at
home or in the work place.
In developing nations, 80% of all diseases are related to poor water quality. It is estimated that
30,000 people around the world die each day due to contaminated water and poor sanitation. In
the United States, wastewater treatment, enforced drinking water guidelines, education and
public health practices have made water-related illnesses such as typhoid fever and cholera
almost unknown.
Our household toilets use 20 liters per flush where they could use 6 liters. Some industrial plants
and municipalities use water bodies as convenient sewers. Rapid growth of urban populations
and the many chemical products that we use and dispose of daily are also factors that must be
considered in the equation which equals increasing rates of surface and groundwater pollution.
Our thirst for water and energy are ever increasing.
Water Conservation – Doing the Same with Less. By using water more efficiently, we will reduce
pollution, health risks and water costs, as well as extend the useful life of existing supply and
waste treatment facilities. Most importantly, we are protecting water supplies for present and
future generations.
Source: Clean Water Life Depends On It! Freshwater Series A-3. Environment Canada. Ottawa.
1992
Water Conservation- Every Drop Counts. Freshwater Series A-6. Environment Canada. Ottawa.
1992
Water – Here, There, Everywhere. Freshwater Series A-2. Environment Canada. Ottawa. 1992
Related and Resource Websites
http://www.cwec.ca/eng/teachers/small%20world.pdf
Activity
1. Students should enter the classroom and respond to the bell work listed on the board.
Have plastic gallon and 2L soda bottles, clearly labeled, at the front of the classroom, or
on each table for students to use as a reference.
Bell work:
How many liters (or gallons) of water do you use a day?
2. Once you have given the students several minutes to respond to the question in their
notebooks ask them to discuss as a class how much water they thought they used and
what did they include in that accounting? List on the board what they include in their daily
water uses. This list will form the start of a list that they will take home and use to
monitor their daily water use as homework.
3. Explain that the United Nations High Commission for Refugees estimates that an
average human needs a minimum of 30 liters of water a day – 5 liters (approximately 1.3
gallons) for drinking and cooking, plus 25 liters (approximately 7 gallons) or more to keep
clean. The average citizen of the United States uses about 425 liters (approximately 112
gallons). How does that compare to what they estimated their use? Why do they think
there is a difference? Often students underestimate how much water they use. Point out
that each time they go to the bathroom they may be using up to 20 liters of water. When
they cook dinner they may use water to both boil food in, clean food, wash dishes, etc.
The figure of 425 liters does not include the water used in producing the electricity that
they use or in the manufacture of items and foods already processed.
4. Share with students a water bill, calculating how much water is being used per day. How
does this bill compare to the daily use by the average American?
5. Add the following to the daily water use chart:
Flushing toilet
Brushing teeth
Bathing/ showering
Cooking
Drinking
Washing dishes
Cleaning
Watering lawn/garden/washing car
Washing clothes
6. Present the homework assignment (see the materials list above) that they should use the
list above as a base and monitor how they use water over the next week.
7. Split the class into groups of four. Each group will be a family of four in an assigned
country.
8. Use the ‘Global Water Distribution Facts’ to determine the amount of water that each
family receives per day.
9. Copy the ‘List of Daily Water Use Chart’ and the ‘Class Water Use Chart’ for student use.
10. Acting as the ‘Global Water Supply’, the teacher asks each group to come up, state their
country and receive the appropriate amount of water.Using jelly beans, for example
Canada receives 235L and therefore 235 jelly beans; you might want to have these
counted out in advance of the lesson.
11. Provide the students with the following rules:
Rule 1
Place 5 jellybeans from your water supply aside. This is polluted water. It should not be
used unless absolutely necessary.
Rule 2
Minimal Life Requirement per family
a. Drinking -12 jelly beans/family
b. Cooking – 10 jelly beans/family
c. Bathing – 12 jelly beans/family
Rule 3
The object of the activity is to use the daily water as efficiently as possible.
12. Have students respond to the following questions.
i. As a family, decide how you will use your water. Enter this amount on the class chart.
ii.
Are you able to perform all the tasks listed under ‘Daily Water Use
in the Home’? Why? Or why not?
iii.
How did you rank the ‘Daily Water Uses’? Explain your answer.
iv.
Based on your class results, which countries waste water most? In
which countries do you think people suffer because there is not
enough water?
v.
Make a chart identifying the amount of water used by each family
for each daily use.
The class water use chart may look like this:
Drink Cook Bath
Wash
Wash Wash Water Wash Flush Total
clothes teeth
dishes lawn
car
toilet
Canada
20
20
40
30
5
10
50
40
20
235
Sweden
15
20
15
15
2
5
15
20
10
117
Zimbabwe 5
6
3
1
1
1
0
0
0
18
Egypt
6
7
5
4
2
2
0
1
1
28
Brazil
7
7
5
5
2
2
0
1
1
30
Croatia
India
9
5
10
6
10
4
15
5
2
1
5
2
5
0
10
2
10
2
76
27
Note: The amount allocated to each family is not based on specific statistics but are estimates
derived from a variety of information sources. The aim of the allocated amounts is for students to
understand that water is not distributed equally.
vi.
Based on our class results, what happens when water becomes
polluted? Do you think that there is enough water on earth that we
can continue to pollute it?
13. Once the chart is complete have students create bar graphs showing the total amounts of
water each family used for each activity.
14. As a class discuss how lack of potable water can impact an individual, a family or a
community.
Homework
Students should list three questions that they have about the availability of water throughout the
world and locally.
Embedded Assessment
Students will demonstrate their ability to discuss water availability in class discussion and in the
creation of 3 questions.