CHAPTER 6 - WATER EFFICIENCY (WE)

Question 1

Conservation focusses on policies and activities to manage the use of water whilst efficiency is the reduction of water needed for a specific purpose.

Answer 1

Water Efficiency versus Conservation

Question 2

defined as trying to reduce water use entirely

Answer 2

Conservation

Question 3

aims to reduce waste by using less for the same task

Answer 3

efficiency

Question 4

regular building occupant who spends 40
hours per week in the project building. Part time or overtime occupants
have FTE values based on their hours inside the building per week divided by
40. FTEs are based on an 8 hour occupancy period per day. An 8 hour (5 days a week) full time occupant has an FTE value of 1.0. FTEs are needed to calculate the baseline, and design case water usage of a building.

Answer 4

Full Time Equivalent (FTEs)

Question 5

FTE identifies the total number of building occupants according to their
occupancy types:

Answer 5

-Full time staff
-Part time staff
-Peak Transients (students, volunteers, visitors, customers, etc.)
-Residents

Question 6

water that meets or exceeds EPAs drinking water quality standards, and is approved for human consumption by state or
local authorities having jurisdiction.

Answer 6

POTABLE WATER

Question 7

domestic wastewater from bathroom and
laundry sinks, tubs, showers and washers. The Uniform Plumbing Code
(UPC) defines gray water as untreated household wastewater that has
not come in contact with toilet waste; the International Plumbing Code
(IPC) defines graywater as wastewater discharged from lavatories,
bathtubs, showers, clothes washers and laundry sinks. Most states will
not allow kitchen sinks or dishwashers to be included with graywater.

Answer 7

Graywater (or greywater)

Question 8

wastewater from toilets and urinals. Most jurisdictions
consider water from kitchen sinks and dishwashers to be blackwater
and it cannot be reused

Answer 8

Blackwater

Question 9

water used for industrial processes and building
systems such as boilers, cooling towers and chillers

Answer 9

Process water

Question 10

runoff water resulting from precipitation that flows
over surfaces, and conventionally into storm sewers or waterways

Answer 10

Stormwater runoff

Question 11

is an EPA sponsored program that promotes and
certifies water-efficient products, programs, and practices.
WaterSense helps consumers identify water efficient products, and
programs that meet WaterSense water efficiency and performance
criteria. Watersense fixtures must use some amount of water (IE.
Waterless urinals do not comply)

Answer 11

WaterSense

Question 12

the flow rate measurement unit for flush fixtures
such as water closets and urinals.

Answer 12

Gallons per flush (gpf)

Question 13

the flow rate measurement unit for flow
fixtures such as faucets, showerheads, aerators, sprinkler heads

Answer 13

Gallons per minute (gpm) -

Question 14

works completely without water or flush valves by
passing urine through a liquid seal.
There are two varieties of waterless urinals: cartridge based and non
cartridge based units.

Answer 14

Waterless urinals

Question 15

water closets use a full flush for solid waste and a half flush
for liquid waste, Dual flush toilets can save around 2/3rd of water used
for flushes.

Answer 15

Dual flush

Question 16

Outdoor water usage, mostly for irrigation, accounts for 30% of the 26 billion gallons of potable water used daily.

___________ can be achieved by using effective practices such as using native/adaptive plants or using greywater for irrigation.

A project pursuing LEED must comply with the prerequisite for outdoor water use reduction of 30%

Answer 16

OUTDOOR WATER USE REDUCTION – WEP1 + WEC1

Question 17

reduce indoor water usage by
20% over the building’s baseline in the prerequisite, and
awards up to 6 points for
further reduction. The Energy Policy Act of 1992/2005
(EPAct) established water conservation standards for water
closets, shower heads, faucets, and other plumbing fixtures.
Water use reduction calculations depend on the number of
FTEs, not the number of fixtures, and the default ratio
between male and female occupants is 1:1.

Answer 17

INDOOR WATER USE REDUCTION – WEP2 + WEC2

Question 18

Conventional toilets

Answer 18

1.6 gpf

Question 19

Conventional urinals

Answer 19

1.0 gpf

Question 20

Private lavatory (bathroom) faucets

Answer 20

2.2 gpm

Question 21

Public faucets:

Answer 21

0.5 gpm (private or public distinction is based on location and use)

Question 22

Conventional kitchen faucets

Answer 22

2.2 gpm

Question 23

Conventional shower heads

Answer 23

2.5 gpm

Question 24

-Residential clothes washer - ENERGY STAR or performance
equivalent
-Commercial clothes washer - CEE Tier 3A
-Residential dishwasher - ENERGY STAR or performance
equivalent
-Prerinse spray valve - consumption ≤1.3 gpm (4.9 lpm)
-Ice machine - ENERGY STAR or performance equivalent, and use
either air-cooled or closed-loop cooling

Answer 24

Standards for specific appliances are as follows:

Question 25

● Install water efficient plumbing fixtures such as: ○ Efficient flow fixtures: lavatories, sinks, showerheads with lower gpm rates ○ Efficient flush type fixtures: dual flush toilets, waterless toilets/urinals, composting toilets, high efficient toilets HET ● Use nonpotable water such as captured rainwater, graywater or municipally claimed wastewater for toilets and urinals ● Use water efficient fixtures, nonpotable water, or municipally treated wastewater ● Treat on-site wastewater to tertiary standards

Answer 25

Water use reduction strategies:

Question 26

raw naturally occurring water bodies, rivers, groundwater, well water, sea water and discharge from open-loop geothermal Percent Improvement calculations = {(Baseline – Actual) / Baseline)} x 100

Answer 26

Exclude water reuse from

Question 27

An integral path to ongoing sustainability is the requirement to know exactly the volume of water used over time. Modern water distribution systems have many components in the project and on its site which results in ample leakage opportunities. Meters are a proactive approach to locating leaks.

Answer 27

WATER METERING – BUILDING LEVEL (WEP3) / SUBMETERING (WEC4)

Question 28

The water metering credit ______________ for the following subsystems: 1. Irrigation water (80% of area) 2. Indoor plumbing fixtures and fittings (80%+) 3. Domestic hot water (80%+) 4. Boilers that use 100 000 g+ / year 5. Reclaimed water (100%) 6. Process water (80%+) – Humidification systems – Dishwashers – Clothes washers – Pools

Answer 28

requires two or more permanently installed system-level water meters

Question 29

part of a building’s HVAC system, and assist with the air conditioning process by cooling water in a closed loop system through evaporative cooling and heat extraction. to maximize the amount of times the water can cycle through the system before being removed by blowdown. This credit requires a one-time potable water analysis to determine the concentration of at least five dissolved solids and ensure maximums are not surpassed. For additional points a project can reduce the concentration levels in makeup water to achieve at least 10 cycles prior to blowdown or use 20% recycled nonpotable water to achieve the minimum of 10 cycles

Answer 29

COOLING TOWER WATER USE - WEC3

Question 30

water used in building equipment such as cooling towers.

Answer 30

Process water