Cutting carbon:
Water
Water
Source: National Energy Education Development Project
Water is a critical natural resource on
which all living matter depends. It is one
of the most important life-support
systems we have on our planet. Without
it, life could not exist and people could
not survive. A person cannot survive for
more than 4 or 5 days without drinking
water (or drinks containing water).
The 3 essential things we all need to do
to conserve water:
1.Bear in mind that water efficiency equals
energy efficiency.
2.Reduce water pollution because it takes
energy and chemicals to clean water.
3.Store more water ourselves and build the
country’s water storage infrastructure.
Potable Water
Water that is safe
to drink is called
potable water.
For water to be
safe to drink it
needs to be
purified. This
process removes
harmful
components from
water but it is
energy intensive.
Using less water
means less
energy is needed
and therefore
fewer carbon
emissions.
Potable water
The water that we get out of our taps is
conveyed via a system of reservoirs,
pump stations, purification systems and
pipelines to individual households and
businesses all over the country.
Electricity is needed to pump water from
reservoirs. Water is also used in
electricity generation, e.g. to cool
nuclear and coal-fired power stations.
All of this cleaning and moving of water
consumes energy which in turn
contributes to climate change, which
influences the hydrological cycle so that
there is less available water. As water
becomes scarce new water sources will
require higher consumption of energy
which again will drive climate change.
For this reason it clearly makes sense to
reduce both water and energy
consumption.
How much water does it take to
produce our food?
Food (per
kilogram)
Water
(litres)
Beef
100 000
Chicken
3 500
Potatoes
5
Water 3
South Africa’s water use
Some scientists predict that South
Africa’s demand for water will exceed
supply within 30 years.
The United Nations warns that within
25 years, half the world’s population
could have trouble finding enough
fresh water for drinking and irrigation.
South Africa is a dry country with an
average of only 500 mm of rain a
year. In fact 65% of the country
receives less than this amount.
Country
Average annual
rainfall (mm)
Thailand
1498
Madagascar
1459
Argentina
1147
New Zealand
1120
Rwanda
1028
United Kingdom
754
France
650
South Africa
520
Pakistan
218
Bahrain
72
Water - how much do we
need?
Human population is growing every
year, so the need for water will also
grow. The individual water needs of
each person are also growing as higher
standards of living and more consumer
goods are within reach.
Further industrial growth is encouraged
to raise levels of employment and
wealth. The new factories that are built
will need more water too.
South Africa’s total water requirements
are growing by about 4% a year. Our
water demand is expected to double
between 2025 and 2030. Our fresh
water supplies may ‘run out’ by 2030.
A project idea:
1. Research ways in which each of South Africa’s
three main water users in the figure above left could
cut back on water use. Be free in your thinking, note
all suggestions, even funny ones.
2. Select the two best ideas and write a proposal in
which you present these suggestions to one another
in the classroom.
3. The agriculture segment could be divided into
irrigated crops and livestock. Find out the
percentage of water used to irrigate crops, and for
livestock.
4. The homes and factories section could also be
divided into separate segments. Find out the
percentage of water used by homes and the
percentage by factories (those producing food and
electricity in particular).
Water 5
How can we ensure future water
supplies?
Water scarcity has been caused by
changes – in the numbers of people,
their needs and wants, and through the
wasteful use of water. If we are to have
enough water in the future, we will
need to change the ways we use it.
We are facing shortages because the
demand for fresh water is beginning to
exceed the supply. We need to find
ways of increasing the supply and
reducing the demand.
Decreasing demand
Water use can be reduced in many
ways:
Check your plumbing: Much water is
wasted through leaks from dripping
taps or old pipes, so repair leaking taps
and pipes.
Just use less: Install water efficient
shower heads, dual-flush toilet
systems and rain water tanks.
Decreasing demand:
Recycle: Use ‘grey’ water from
washing clothes and dishes,
bathing and showering to water the
garden.
Government intervention: Water
Pricing Systems have been set up
to control the demand of water. This
is done by supplying every
household with some free, or
inexpensive water, and then
charging progressively higher
prices when additional water is
used. People who use a lot of water
have to pay more for doing so.
Market-based pricing of water:
Because water is not expensive, it
may be over-used. Sometimes
governments charge users such as
agriculture or industry a lower,
subsidized rate for water. Many
people feel that all users should
pay the same price for water.
Water 7
Increasing supply:
The following measures could be
undertaken to increase natural water
supply:
Use less: the cheapest and most
effective way to increase water supply is
for everyone to waste less and to use
every drop of water sparingly. Whenever
possible, water should be used more
than once.
Construct new dams: Unfortunately,
there are many problems associated with
building new dams and people disagree
about the value of having more dams.
Discuss some of the advantages and
disadvantages you can think of.
Conserve Wetlands: Wetlands help
ensure a clean and consistent flow of
water, so they should be conserved
wherever possible.
Water harvesting: Capture and store rain
water that would otherwise run off and
not be available for human use. Install
gutters and rain water tanks to collect
rain water from your roof.
Other strategies to increase water
supply, such as desalinating seawater
and fog harvesting are technically
feasible, but their impact on the ecology
needs to be monitored.
To decrease surface water loss due to
evaporation, water your garden in the
morning or evening, not at midday.
Activity 1: Are you water-wise?
Answer the following questions. Take
a few days to research the more
difficult ones and then share your
findings with one another. See if any
water saving project ideas emerge
from the discussion.
1. How old will you be in 2030 when
scientists predict South Africa will ‘run
out’ of fresh water?
2. Where do you live?
3. What is the name of your nearest
river?
4. Are there any wetlands in your
area?
5. Where does your drinking water
come from?
6. How is water being wasted in
your area?
7. How could you prevent water
being wasted in your area?
8. Have you ever experienced a
water shortage in your area?
9. Does your family or school
harvest (collect and store) water?
Explain what you do.
10. Is South Africa the only country
facing the prospect of serious water
shortages? Where else might
this be a problem?
Water 9
Activity 1: Results and Notes
Activity 1: Results and Notes
Water 11
Activity 2: Measure your water use for one day
Before we can ask others to cut back on their water use it is
necessary to look at how much water we ourselves use each
day.
This is how you could conduct your own water audit:
Purpose of the audit:
1. To find out which of your daily activities use the most water.
2. To identify how you could save water.
Include other activities that use water that have not been
included in the audit sheet on the next page – things like
washing the car, refilling the swimming pool, water used for
cleaning your house, watering the garden etc.
NB. Please keep this audit sheet with you and update it
throughout the day.
Hints:
• Showering: Get one person to stand in the shower holding a
bucket at the shower rose. Switch on the tap at the volume you
would usually use for showering. Time one minute. Measure the
volume of water in the bucket. Now everyone just needs to
record their showering time and multiply it by the volume in the
bucket.
• Cleaning teeth and washing hands: Similar to the above
method. Hold a jug under the tap and switch on the tap at the
flow rate you would use when you brush your teeth. Measure
how much water you collect and multiply this by the number of
times you brush your teeth each day.
• Flushing toilet: estimated 40 litres/day/person.
• Bathtub: a 130x50x30cm bath takes 195 litres to fill, 48.5 litres
for quarter filled.
Activity 2: Measure your water use for one day
Day 1
Lunch
to
supper
Before
Lunch
No.
Amount
No.
After
Supper
Amount
No.
Total
Amount
Glasses of
water
(340 ml)
Cups of
coffee/ tea
(250 ml)
Brushing
Teeth (ml)
Washing
Hands (ml)
Flushing
Toilet (l)
Showering
(l)
Washing
Clothes (l)
Washing
Dishes (l)
Cooking (l)
Other (l)
Other (l)
Total:
Amount
Activity 2: Results and Notes
Activity 3: Find out about water use in your area
1. How much do you pay for one litre of water?
2. How much water does your school use in one month? Find
this out by looking at the monthly water account.
3. How much does your school pay per litre of water?
4. Compare the cost of water with the following items:
– A litre of coke
– A litre of milk
– A litre of petrol
5. Does your family ever discuss saving water?
6. Does your family talk about water quality/health issues?
7. Is the availability of water a major concern in your
community?
8. What number would you phone if you noticed a leaking water
pipe in your area? If you do not know, try to find out! Was it
difficult to find this number?
9. What number would you phone if you noticed sewerage
flowing into a river in your area? If you do not know this number,
try to find it out. Was it difficult to find this number?
10. Try phoning the above numbers to report a leak. What
responses did you get?
11. Which government department is responsible for making
sure you get clean drinking water ?
12. Do you have a local reservoir or dam that stores water for
your use? If so what is the name of the dam or reservoir?
13. Has this reservoir or dam ever run dry, or nearly dry?
14. Has this reservoir or dam ever been polluted?
15. What could you do to encourage people to use water
efficiently?
Water 15
Activity 3: Results and Notes
Activity 3: Results and Notes
Water 17
Down
2. Water becomes this when
frozen
3. Taking salt out of sea water so
that it can be used.
5. Growing of plants for food
7. The process describing when
water turns into a gas or 'dries up'
8. A 4,5 tank can be used to store
this 'free' water
12. Water in a gas state
13. City living
16. Water ________ countries do
not have a lot of water
Water 19
This booklet has been printed on Triple Green, an
environmentally friendly paper produced in South
Africa. The fibre composition of Triple Green
includes on average 60% sugar cane. This fibre
(Bagasse) is the remaining fibre after sugar has
been extracted from the harvest cane.