EPG: Chapter 7 - Water Efficiency

Question 1

In the US, buildings account for ___% of all potable water consumption.

Answer 1

14%

Question 2

People use potable water not just for drinking but for ___, ___, and ____.

Answer 2

irrigation / handwashing / flushing toilets

Question 3

A lot of energy, cost, and infrastructure goes into treating water so it is safe to drink, so it is ___ to use potable water for purposes in which it is not required.

Answer 3

wasteful

Question 4

aerator

Answer 4

a water flow constrictor attached to the tip of an indoor water faucet to limit the amount of water that flows out of it

Question 5

baseline case

Answer 5

a standard from which a basis of change can be measured for improvement

Question 6

blackwater

Answer 6

water from toilets and urinals that is considered under all codes to be wastewater. some states also consider water from kitchen sinks, showers, and bathtubs to be blackwater.

Question 7

cooling tower

Answer 7

a structure that regulates air temperature in a facility by using water to absorb heat from air conditioning systems

Question 8

design case

Answer 8

the actual project design metrics that are compared to a baseline to show efficiency gains

Question 9

drip irrigation

Answer 9

water delivered at low pressure directly to the roots of a plant

Question 10

EPAct of 1992

Answer 10

requires that all toilets use no more than 1.6 gallons of water per flush and all urinals no more than 1.0 gallon per flush, among other requirements. This standard is used in the LEED Water Efficiency (WE) category to calculate the baseline daily water usage of a project.

Question 11

evapotranspiration

Answer 11

amount of water lost through evaporation in irrigation

Question 12

full-time equivalent (FTE)

Answer 12

the designation for a building occupant who spends 40 hours per week in the project building. Transient occupants have FTE values based on their hours per week divided by 40.

Question 13

graywater

Answer 13

untreated household wastewater that has not come into contact with toilet waste (ie wastewater from bathtubs, showers, bathroom sinks, and washing machines. does not include wastewater from kitchen sinks or dishwashers).

Question 14

lavatory

Answer 14

aka bathroom sink

Question 15

potable water

vs

not-potable water

Answer 15

water that is treated to a standard that makes it safe for human consumption

water collected from a variety of sources, that has not been approved for human consumption but can be used for irrigation and toilet flushing

Question 16

reclaimed water

Answer 16

wastewater that has been treated and purified for nonpotable uses. Commonly effluent from a wastewater treatment plant that at least removed harmful pathogens, organic material, and heavy metals.

Question 17

submetering

Answer 17

the installation of submeters on water systems to allow buildings to track water usage trends, monitor fixture performance, and identify leaks

Question 18

water closet

Answer 18

aka toilet

Question 19

WaterSense

Answer 19

a partnership program by the US EPA that brings together a variety of stakeholders to provide customers with easy was to save water, as both a label for products and an information resource to help people use water more efficiently

Question 20

What is the water balance approach?

Answer 20

bases projected water usage on the annual amount of rainfall in the region of the project. The building is designed to use only as much water as it can harvest.

Question 21

What is the efficiency first approach?

Answer 21

The project team looks on how to use water efficiently first. Then they consider alternative water sources (ie rainwater, water reclamation, and on-site treatment)

Question 22

In the WE category rating system, a project obtains credits through its ability to reduce water use below a set _____.

Answer 22

baseline

The more a project reduces water use from baseline the more points will be awarded.

Question 23

What is the design case in the WE category?

Answer 23

It is the building’s projected water usage and the team’s goal for achieving water efficiency. There are water use calculators provided by LEED to calculate the baseline and design case for water efficiency.

Question 24

What data is needed in order to calculate the daily water use? (2 things)

Answer 24

• maximum and minimum flow rates established by the EPAct of 1992
• number of building occupants & their average daily water fixture use

Question 25

The full-time equivalent (FTE) is a calculation used in all rating systems for the ___, ___, and ___ categories.

Answer 25

WE, EA, and EQ

Question 26

An occupant who is in the building for 8 hours a day receives an FTE of ___.

Answer 26

1.0

Question 27

What are two ways to dispense water from a building?

Answer 27

flush fixtures and flow fixtures

Question 28

Give examples of flush fixtures and flow fixtures.

How is water usage measured for each?

Answer 28

flush: toilets, urinals. measured per flush
flow: faucets, hoses, dishwashers. measured per minute (usually)

Question 29

The goal of the WE category is to reduce the amount of _____ water used for purposes other than drinking and to treat and reclaim all _____.

Answer 29

potable

graywater

Question 30

What are the 3 types of water usage for the LEED BD+C rating system?

Answer 30

indoor, outdoor, and process water

Question 31

What is the best way to reduce water use, regardless of the type of water use?

Answer 31

measuring or metering water use is the first+last strategy for each type of water usage.

Question 32

According to EPA, about ____% of the total water used daily is used indoors.

Answer 32

70%

Question 33

LEED v4 requires a min of a ___% reduction of the baseline for water used indoors. (as part of the WE Prerequisite - Indoor Water Use Reduction)

Answer 33

20%

Question 34

WE Prerequisite - Indoor Water Use Reduction requires projects be installed with high-performance flush & flow fixtures carrying the _____ label.

Answer 34

WaterSense.

It is an initiative created by EPA to promote water-saving products.

Question 35

Ultra-low-flow water closets

Answer 35

aka high-efficiency toilet (HET). Has a pressure tank to produce a pressure-assisted flush. These fixtures usually require more maintenance than a typical fixture so are more common in commercial/industrial settings.

Question 36

Dual-flush water closets

Answer 36

provides flush option for liquid waste and solid waste.

Question 37

Ultra-low-flow urinals

Answer 37

urinal that uses reduced amount of water to flush liquid waste. Has an optimized valve that produced a pressure-assisted flush.

Question 38

Low-flow aerators

Answer 38

Water & energy-saving device that replaces the existing aerator on a faucet. In water faucets, they can restrict the flow up to 50% and has a mixer to increase air in the water to provide the feeling that the flow has not changed.
For commercial projects, they are a low-cost alternative to replacing fixtures entirely.

Question 39

Waterless urinals

Answer 39

They are popular due to their water savings and found usually in large venues like sports stadiums and museums. Because of high, regular maintenance, note that they are not entirely waterless.

Question 40

Composting toilet

Answer 40

a single unit fixture with a composting compartment or many units connected to a remote composting tank. Aerobic microorganisms break down the waste using available water and oxygen. This reduces the waste volume down to 1-2%.

Question 41

What climates commonly use harvested rainwater?

Answer 41

partially arid areas and other areas with limited water availability.

Question 42

What are some standard precautions when utilizing graywater?

Answer 42

• backflow prevention

- limit the surface discharge of graywater.

Question 43

WE Prerequisite - Building-Level Water Metering requires submeters to be ____ installed.

Answer 43

permanently

Question 44

Installing submeters can reduce overall building water consumption by ___-___% in the first few months.

Answer 44

30-40%

Question 45

WE Credit - Water Metering rewards a point to teams that install submeters on two or more of what kinds of applications?

Answer 45

• irrigation systems
• indoor plumbing fixtures & fittings
• domestic hot water heaters
• boilers
• reclaimed water systems
• other process water (ie humidificaiton systems, dishwashers, clothes washers, and pools)

Question 46

Process Water

Answer 46

water used for industrial purposes (ie boilers & cooling towers. For hospitality projects it could be dishwashers, laundry machines and ice machines)

Question 47

closed-loop systems

Answer 47

water circulation system for industrial purposes that can reduce potable water; allow process water to be reused for many cycles.

Question 48

Xeriscaping

Answer 48

landscaping desig that utilizes soil improvements, efficient irrigation, and native & adapted plant species to reduce water usage.

Question 49

What is the most efficient form of irrigation?

Answer 49

drip irrigation. It is considered to be 90% water-efficient in contrast with traditional sprinklers.

Question 50

Nationally, outdoor water use accounts for approx ___% of average household water use. It also accounts for almost ____ gallons of water per day, mainly for landscape irrigation.

Answer 50

30%

9 billion!!!

Question 51

What is the first step in using a nonpotable water source for irrigation?

Answer 51

capturing and collecting rainwater.

Question 52

cisterns

Answer 52

large rainwater collection and storage tanks. usually used for commercial projects.