GEOS1701 Environmental Systems, Processes and Issues
WATER USE ASSIGNMEN
1. INTRODUCTION
Australia is the driest continent on Earth and just a few years ago we were in the midst of a severe
drought with bushfires raging throughout NSW.
Water levels in Sydney’s Warragamba dam, our
main source of drinking water, reached an all-time low. The last few years have been wet and dam
levels are full again, but we will inevitably go back into a drought cycle in the near future thanks to
our climate. Water availability will always remain a long-term issue in Australia and Sydney.
So, here’s a question for you: how often do you think about how much water you use at home?
Probably not that often!
We all take the availability of fresh water for granted.
Is this complacency
an environmentally sustainable attitude?
It’s easy to think so after an extended period of rain when
dams are full, but we’re only the next drought away from major water use restrictions. Do you know
how much water you or your household use each day?
Or how do you use it?
In this assignment you’ll be asked to monitor water use in the house, apartment or college where
you live in order to understand some of the factors associated with domestic water usage and how
you may improve your own water usage in the future.
Why are we asking you to do this? This course is fundamentally about physical environmental
science and environmental management issues. Water is the Earth’s most important environmental
resource. Not only does it shape our landforms and control our climate, it is also a basic requirement
for our survival.
Without an adequate supply of fresh water, human populations simply cannot
survive.
It is also a renewable resource and today’s freshwater supply is the same as when
civilization began, yet water shortages are common globally.
Sydney’s variable rainfall patterns over time requires it to store more water per capita than most
major cities in the world.
It is therefore of major concern that the predicted growth in Sydney’s
population will mean finding even more storage capacity or reducing our usage even further when
the next drought occurs.
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Although water is freely used in the home, most individuals have little real idea of the quantities
they use directly.
Water use figures are normally derived from the total used divided by the number
of users.
Hence the average Sydney consumption figures may also include some commercial and
industrial use so it is fairly misleading in terms of domestic use.
Therefore, monitoring the rate of
water use in the home, flat, or unit can provide useful insights into the actual domestic amounts of
water used over specific times by a family or by an individual “at home”.
Your household water use includes all water used inside the house and outside on gardens, car
washing etc.
Sydney Water reports that most of the water consumed in the home is used in bathing
or showering (32%), flushing toilets (20%), washing clothes (12%) and using inside taps (12%).
Outside uses amount of water to around 23% of total water used
(https://www.sydneywater.com.au/education/drinking-water/water-use-conservation.html).
Of
course, these are average figures and the relative proportions, as well as the total amount of water
used, will vary widely from home to home and person to person.
In this assignment you’ll basically be designing and running your own experiment to monitor
domestic water usage where you live. This is a huge benefit for a first-year student because you will
get hands on experience at collecting data, analyzing it and writing a report using both your own
data and results and comparison with existing data in the scientific literature. These are core skills
that all scientists must learn and develop in their career. Even if you have no intentions on becoming
a scientist, doing this project will almost certainly make you think about how you use water for the
rest of your life!
1.1. Aims
The overall aim of this assignment is to understand and explain the volumes and patterns of water
use in the place that you live over a continuous period of at least 20 days.
There are several distinct and different objectives you will be required to do to achieve this aim. You
will need to:
i)
quantify the major types of water use in your home (eg drinking, bathing, gardening, cleaning
etc.) and explain how these vary both in terms of amount and over time;
ii)
compare your own daily use with the average per person daily use in your household;
iii)
estimate the water balance for your home by comparing water usage with the volume of
rainfall yield from your roof;
iv)
assess the importance of different factors on water use patterns, such as weather and
household activities; and
v)
compare your water use to the rest of your class and Sydney as a whole.
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1.2 Learning Outcomes
This assignment is directly related to several of the Course Learning Outcomes that are
documented in the Course Outline:
• CLO2. Critical thinking and problem solving
–
Formulate and solve real problems in relation to environmental data using basic
statistical analysis and geo-spatial software;
• CL03. Written communication
– Construct written and analytical work in the format of a scientific report;
– Convey data, statistics and graphical results so that non-experts can understand the key
outcomes of analyses;
– Self-manage successful time management strategies;
• CL04. Personalized, self-guided, flipped classroom and blended, learning skills
– Complete independent research and learning using a variety of internet based resources
and computing skills;
• CL05. Practical skills
– Describe and apply the appropriate methods, techniques, and approaches used to
monitor and measure different physical environments;
– Use word processing, data spreadsheet and geo-spatial software.
2. METHODS
There are four (4) different tasks required to gather your data for the report.
These are:
i) measure the water use in your home;
ii) observe and record some daily weather data;
iii) record different household activity patterns; and
iv) calculate the water yield from the roof of your house..
The specific details of these required tasks are as follows:
i)
Measure the water use in your home
You have to monitor the daily water use at your place of living for a continuous period of at least 20
days.
You also need to ensure three full weekends are included. There are two techniques that can
be used to monitor your household water use:
a) Water meter method.
If your residence has a water meter, find out where it is and record the
meter reading once a day, preferably either early in the morning or late at night.
Ensure that you
are consistent in your time of reading in order to get an accurate daily use in liters.
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If you live in a block of flats there is probably only one meter for the entire block.
For blocks of 10
units or less it is worthwhile to read this meter as part of your study period to investigate trends in
water use for the entire block.
For those living in larger apartment blocks or student colleges, the
meter may be in a locked room and therefore not accessible. If this applies to you, then try
contacting the manager of the apartment block or college and see if they can allow you access for
the duration of your study.
Make sure you understand what the numbers on your meter are recording: eg liters, tens of liters
or kilolitres.
If possible, test your meter’s operation. You can do this by watching the meter while
somebody runs a tap. Or you can read it before and after a toilet flush.
b) Chart method.
Keep a track of water usage using a system of home-made charts where you
record information such as:
• the number of toilet flushes,
• number and duration of showers,
• other tap usage (hand washing, brushing teeth, drinking water etc.)
• clothes washing etc.
Your charts should also allow you to identify water use for specific family members.
Let’s hope this
doesn’t cause embarrassment within the family!
For students without a water meter the chart method is the ONLY data collection method that you
can be used.
For students with a water meter, you will also need to use the chart method for at least
10 of the 20 days of your study (in addition to reading the water meter each day) so you get an idea
of how much water is used for different purposes in your home.
These 10 days should also be done
consecutively.
You must have a good system of charts set up otherwise your project will fail.
Be creative and give
them some thought before you start using the charts. Ask your family or flatmates to be honest
when filling them in!
Some of you live in college or share accommodation and it will be more difficult
to keep a track of water use.
You will have to be creative, and it is a good idea to discuss your
situation in the course Tutorials, or separately with the course convenor Prof Rob Brander to come
up with a system that will work for you. No doubt there will be some problems for some of you and
we’ll explain how to deal with these in the first few labs of the course.
The values in Table 1 can be used to assist in calculating water usage based upon frequency of
selected activities.
Please only use this table as a guideline – there are many other ways to get more
accurate estimates of water volumes used. Appliances will vary so check the manual and where
possible, try measuring it yourself with some graduated cylinders, buckets or any container with a
known volume – we like to see initiative and effort like this!
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ii)
Observe and record daily weather
Maximum and minimum temperatures as well as rainfall data can be obtained from the Bureau of
Meteorology Website
http://www.bom.gov.au/nsw/observations/sydney.shtml.
This data is for a
limited set of recording stations and you may live some distance from these.
Given that rainfall in
Sydney is spatially variable, this may affect the validity of your results so you can always make your
own rain gauge.
A straight-sided bucket will do fine.
Google it! Measure the depth of water in it at
the same time every day.
Make sure to empty it after each measurement and try to put it as far
away from buildings, trees etc. as possible and devise a way to keep it weighted down so that it
won’t be knocked over.
Table 1. Average use of water by domestic activity according to Sydney Water
(www.sydneywater.com.au). This is a guide only.
Type of Water Use Volume of Water Used (in Litres)
Regular shower head 10 L per minute
Water efficient shower head 6-7 L per minute
Average bath 110 L
Single flush toilet 11 L per flush
Older dual flush toilet (1983s model) 11 L full flush; 5.5 L half flush
Modern dual flush toilet (2005 or later) 4.5 L full flush; 3 L half flush
Hand basin (running tap)* 4 L per minute
Bathroom wash basin (half full)** 4-6 L
Dishwashing by hand 15 L per wash
Old dishwasher (pre-2014) 13 L per load
Average dishwasher 12 L per load
Front loader clothes washing machine 65 L per load
Top loader washing machine 110 L per load
Garden outdoor tap 15 L per minute
Garden sprinkler 999L per hour
Car washing (hose) 180 L per wash
Car washing (bucket) 99 L per wash
*Washing hands, brushing teeth, etc.
**Shaving, etc.
iii)
Record household activity patterns
Many households have distinct patterns of water use that can be explained by household activity
rather than other factors such as weather.
For example, when does your household do most of its
laundry?
Does everyone in the household go to work, school or uni?
There are times when many
members of the household are absent?
Did you have a party during the observation period?
Think
about anything that may affect your daily water use.
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iv) Calculate the water yield from the roof area of your house (or apartment block)
The water yield is simply the amount of rainwater (ie volume) that falls on top of the roof of your
house or apartment building. The idea here is that we want you to think about sustainability – could
you potentially have lived off of the amount of water that fell on your roof as rain during your
monitoring period?
To work out the water yield, you first need to calculate the area of the roof.
There’s no need to get
too fussy here in terms of accuracy.
If you can measure your house dimensions to the nearest half
metre, that will be fine.
For some people living in flats and units, the roof area for their specific flat
may be difficult to calculate.
To get around this, just calculate the overall roof area for the entire
building and divide that by the number of flats/units in the block. Google Earth can allow you to
calculate your roof and block area using the path function quite easily (we will demonstrate this in
the lab classes).
Once you know the area of your roof you can then calculate the volume of water yield by multiplying
the depth of rainfall by your roof area. You can do this by using both the rainfall recorded during
your observation period and if you really want to get into sustainability, look up the average annual
rainfall for your area.
Long term rainfall data can be obtained from the Bureau of Meteorology web
site or from local rain gauges as discussed earlier.
3. REPORT STRUCTURE
You will prepare and hand in this assignment in the format of a scientific report, which involves
the following sections:
Abstract – Introduction – Methods – Results – Discussion – Conclusions – References – Appendices
More information about what to include in each of these sections is given in Appendix 3 in this
document and will be
discussed in the Week 5 Lab Class.
3.1 Discussion Questions
One of the key aspects of this assignment involves interpreting your results. In the Discussion section
of your assignment, we will be looking for the following research questions to be addressed
(amongst other really interesting findings arising from your results!):
i) How well do the total water use values obtained from the water meter agree with those from
the chart system?
Try to account for any major discrepancies (Please note that if you do not
have access to a water meter, you won’t be able to comment on this).
ii) What temporal patterns of water use did you find? (eg differences between water use on
weekdays vs. weekends or during the day);
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iii)
Did the weather have any influence on your water use?
iv)
Can you account for any major variations in the daily water use at your home?
v)
Is there a water hog in your midst? In other words, do some people use more water than
others?
vi) Think about sustainability. Could you have lived off the water yield from your roof during your
measurement period?
vii)
How does your household’s water use compare to average water consumption figures for the
rest of your class and for Sydney?
4.
ASSIGNMENT LOGISTICS
Value: The Water Use Assignment is worth 30% of your final course grade.
Submission: This consists of two components:
i) A Data Summary worth 5% of your final course grade to be submitted online on Moodle using by
5 PM on Monday July 7 (start of Week 6).
An example of the data to be submitted is shown in Table
2. You will be given further instructions on how and where to submit this data in the Lab Classes.
The class dataset will be provided to you later in Week 6 and it can be used to address Discussion
question (vii).
Table 2. Example of water use data to be submitted for the Class Dataset. Please note that
fictional sample data are shown.
Your
Student ID
Average total
water use per
day for your
household
(litres)
Average
Number of
people in
Household
Average total
water use per
day per
individual
Major use of
water*
Postcode
of your
suburb
z3019999 1200 4 300 Shower & Bath 2031
*this will be in the form of a drop down box to select from
ii) A Final Report that is due Wednesday July 16 (Week 7) by 10 pm. Please submit your report
online in pdf format (or Microsoft Word) using the Turnitin Link provided in the Week 7 section on
the Course Moodle page.
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The main assignment report will be presented in scientific format as described in Section 3 and
Appendix 3 and your Tutorials. It has a maximum word limit of 2000 words of text and will consist
of a number of Tables and Figures (diagrams, graphs etc.). Please note that there is no limit to the
number of Tables and Figures you can include, and the word limit does not include text associated
with the abstract or reference list or captions and text that are part of Tables and Figures.
Please pay careful attention to the word limit because you may be penalised by exceeding it.
Some
students often ask if it is okay to exceed the limit by 10%?
The short answer is no. If you are over
the limit, then please edit your report to come in under it.
And yes, all words count towards the
limit – we don’t ignore words like ‘the’ or ‘and’ etc.
Late Penalty: UNSW has a standard late submission penalty of 5% per day (of the value of the
assessment) capped at five days from the assessment deadline, after which a student cannot submit
an assessment.
There are no exceptions unless an extension is provided. Extensions are only
provided by the Course Convenor (Professor Rob Brander) for valid reasons (medical or otherwise).
Students with Equitable Learning Plans (ELP) should contact the Course Convenor in advance if they
require an extension.
Guidance: Some of the Labs in the course will have time devoted to the Water Use Assignment:
Week 1:
Introducing the assignment;
Week 2:
Question and answer session;
Week 4:
Question and answer session;
Week 5:
Workshop on how to work with your data and write the report.
You are welcome to reach out to the Course Convenor at any time via email if you have any
questions.
5. FINAL COMMENTS
Do not be overly concerned about the length of these instructions and the scope of the assignment!
The background information is intended to help you get started.
The assignment is not overly time-consuming BUT you are required to think about your own interaction with a valuable resource.
Therefore, in order to gain any wisdom from this exercise
DO NOT ALTER YOUR WATER USAGE
HABITS AND ENCOURAGE PEOPLE YOU LIVE WITH NOT TO EITHER!!!!! Remember that this
assignment is not about you, it’s about how we use a critical natural resource and issues of
sustainability.
No one will be marked down if they take 15 minute showers!
You have six weeks to finish the project and so the earlier you start monitoring, the better:
remember that you need to monitor over at least 3 weekends.
Your dedication to monitoring using
the water meter and/or charts is crucial and you should make as many observations as possible, eg
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on what days was the washing machine used, note down the number of any visitors etc.
Getting
the data should be fairly easy, but if you have problems with data collection, contact the Course
Convenor or raise them during your Labs.
In the Appendices you will find some information to help you on your way with some of the
calculations required as part of the report and a general overview of how to structure the report
and the proper use of reference sources.
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APPENDICES
Appendix 1. Calculations and Conversions
Here are some simple descriptions of some of the variables and calculations you will be involved with
(note that units of liters are given as L):
Mean daily household water use (L/day) = Total water use (L) divided by total number of
days of observation
Mean daily water use per person (L/day/person)
=
Mean daily household water use divided
by the mean number of people in the
home
Rainfall Volume (m3)
=
Area of roof (m2) multiplied by Depth of Rainfall (m)
(Note: you will have to convert rainfall from mm to m: 1000 mm = 1 m)
Water Yield (L) = Rainfall Volume (m3)
x 1000 (ie there are 1000 liters in a cubic meter)
(As a general rule each m2 of your roof will yield 1 liter for each mm of rainfall falling on it.
For example, 10 m2
roof area will yield 100 liters from 10 mm of rain)
If you are keen you can attempt to work out an Annual Water Balance for your roof. This basically means
the difference between how much water fell on your roof and block in a year minus how much water
you would have used in a year based on your short-term results. To do this you will need to search how
much rain falls in a typical year in your area. This data can be sourced from the Bureau of Meteorology
website.
Example calculation of Annual Water Yield for Roof:
Roof size = 100 m2
Average annual rainfall = 1200 mm
= 1.2 m
Average annual volume of rainfall on roof
= 100 m2 x 1.2 m
= 120 m3
Annual Water Yield = 120 m3 x 1000
= 120 000 L
Example calculation of Annual Water Balance for Roof:
Mean daily household water use
= 1400 L per day
Mean annual household water use
= 1400 L x 365 days
= 511 000 L per annum (year)
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