Water efficiency

1. T H E B A S I C S I N G R E E N D E S I G N A N D
G R E E N C O N S T R U C T I O N
P A R T 3
W A T E R E F F I C I E N C Y
Green Building 101

2. Introduction
In this series we are going to discuss what green
building is and explore some of the general strategies
used in this type of construction.
This is meant as an introductory course, so there won’t
be a lot of detail presented.
Resources are listed at the end of each episode for
those who want more information.
Thanks for viewing!
Photo courtesy of Daren through a Creative Commons License
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3. Water Efficiency
 As the name suggests, here we will be looking at
ways to make water use more efficient. This includes
domestic water use (drinking, cooking, washing,
flushing) and irrigation.
Photos courtesy of Jerome Pagunsan and Sarah Rifaat through a
Creative Commons License
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4. Water Efficiency
 Water is a precious resource that needs to be
conserved and reused so we don’t run out. Strategies
for doing this include:
 Proper selection of landscape plant materials and irrigation
systems
 Use of high efficiency plumbing fixtures
 Water reuse and treatment systems
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Photo courtesy of JL Johnson through a Creative Commons License

5. Landscaping
 The use of native,
adapted, or drought-
tolerant plants is the first
step to reducing the
amount of water used in
landscaping.
 Native and adapted
plants are suited for the
climate of the project
location, and do not
usually require
additional irrigation.
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Photo courtesy of Maegan Tintari through a Creative Commons License

6. Landscaping
 Drought-tolerant plants
are acclimated to long
periods of time without
water.
 Generally speaking, grass
lawns are not conducive to
lowering the amount of
irrigation water needed.
They require regular
watering and lots of
maintenance.
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Photo courtesy of Swallowtail Garden Seeds through a Creative Commons License

7. Irrigation
 There are a few options
for reducing irrigation
water use.
 One is to install a
moisture sensor system,
so the sprinklers only run
when there is not enough
moisture in the ground
(this keeps them from
running while it is
raining or just after a
rainstorm).
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Photo courtesy of JFXIe through a Creative Commons License

8. Irrigation
 Drip irrigation systems
ensure that water is
delivered directly to the
plants (not spraying on
the building or
sidewalks), and deliver it
very efficiently, with less
waste.
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Photo courtesy of Christian through a Creative Commons License

9. Irrigation
 Temporary drip
irrigation systems are
often used when
landscaping is first
planted, allowing the
plants to get established.
 These systems are then
removed as the native or
adapted plants acclimate.
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Photo courtesy of J’ram DJ through a Creative Commons License

10. Plumbing Fixtures
 These days there are
several water efficient
fixtures on the market,
some of which are now
required by local codes.
 High efficiency toilets
(HETs) use a gallon or
less per flush.
 Dual-flush toilets use less
water for liquid waste
and more for solids.
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Photo courtesy of Jim Larrison through a Creative Commons License

11. Plumbing Fixtures
 There are low-flow and
waterless urinals, low-flow
shower heads, and
sensored faucets that limit
the amount of water per
use.
 You don’t have to invest in
all new fixtures to reduce
water use. A 50 cent
aerator in the bathroom or
kitchen faucet or a new
efficient showerhead can
work just as well.
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Photo courtesy of tanakawho through a Creative Commons License

12. Appliances
 High efficiency clothes
washers and dishwashers
greatly reduce the
amount of water used per
load. They also save
energy, so are double
winners!
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Photo courtesy of Megan through a Creative Commons License

13. Water Reuse and Treatment
 As was mentioned in the
Site episode, water on-
site can be treated and
reused again.
 With plumbing waste
water there are two types
of reuse systems, gray
water and black water.
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Photo courtesy of William Herron through a Creative Commons License

14. Water Reuse and Treatment
 Gray water is the water
that comes out of
bathroom sinks, showers,
dishwashers, and
washing machines.
 It is considered to be less
contaminated than black
water (described below).
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Photo courtesy of nerissa’s ring through a Creative Commons License

15. Water Reuse and Treatment
 With minimal filtration
gray water can be used in
irrigation or to flush
toilets and urinals.
 With additional filtration,
gray water can also be
used for drinking and
cleaning.
 Note that these systems
require a separate piping
system for the treated
gray water.
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Photo courtesy of Claire Cessford through a Creative Commons License

16. Water Reuse and Treatment
 Black water comes from
toilets and kitchen sinks.
 Extensive treatment is
required before it can be
reused for any purpose.
 These systems involve
several filters and
treatment with
ultraviolet light.
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Photo courtesy of Joe Shlabotnik through a Creative Commons License

17. Water Reuse and Treatment
 Black water treatment
systems are available for
both commercial and
residential applications.
 The most cost effective
option is usually to
connect several large
buildings together with a
central treatment plant.
But, it can be done on a
smaller scale too.
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Photo courtesy of Rick Kimpel through a Creative Commons License

18. Summary of Water Strategies
 Landscaping – Use drought tolerant, native, or
adapted species that are acclimated to needing less
water. Limit use of grass lawns.
 Irrigation – Drip systems and moisture sensors
help to deliver water more efficiently to plants only
when they need it.
 Plumbing Fixtures – Use high-efficiency fixtures
or retrofit current fixtures.
 Water Reuse and Treatment – Recycle water on
site for flushing or treat to potable standards.
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19. Knowledge Measurement
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 Thanks for your interest in learning about Green
Building. If you want to test what you’ve learned
about this subject, try your hand at the five multiple
choice questions in the next slides.
 Resources for additional information are available on
slide 30.

20. 1. What is the first step in reducing the amount of
water used for irrigation?
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A. Planning planting areas
B. Use of native and drought-resistant plants
C. Planting perennials
D. Not using grass

21. 1. Answer
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B. Use of native and drought-resistant plants
(See slide 5)

22. 2. Drip irrigation systems ensure that water is
delivered directly to the plants.
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A. True
B. False

23. 2. Answer
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B. False
(See slide 8)

24. 3. High efficiency clothes and dish washers are
double winners because they save:
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A. Time and energy
B. Money and time
C. Water and energy
D. Water and time

25. 3. Answer
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C. Water and energy
(See slide 12)

26. 4. What are the two types of waste water?
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A. Green and black
B. White and black
C. Clean and dirty
D. Gray and black

27. 4. Answer
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D. Gray and black
(See slide 13)

28. 5. What additional treatment is needed in black
water treatment systems?
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A. Black light
B. High-density filter
C. Ultraviolet light
D. None of the above

29. 5. Answer
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C. Ultraviolet light
(See slide 16)

30. What’s Coming Up?
In the next episode, we will continue to look at green
building strategies, focusing on Energy Efficiency.
Resources:
Xeriscaping (water efficient landscaping)
http://eartheasy.com/grow_xeriscape.htm
WaterSense program from the EPA http://www.epa.gov/watersense/
On-site waste water treatment http://ossf.tamu.edu/onsite-wastewater-
treatment-systems-owts/
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