EPG: Chapter 7 - Water Efficiency Flashcards
LEED Green Associate Exam Preparation Guide LEED v4 Edition - Key Terms and Concepts in Chapter
In the US, buildings account for ___% of all potable water consumption.
14%
People use potable water not just for drinking but for ___, ___, and ____.
irrigation / handwashing / flushing toilets
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.
wasteful
aerator
a water flow constrictor attached to the tip of an indoor water faucet to limit the amount of water that flows out of it
baseline case
a standard from which a basis of change can be measured for improvement
blackwater
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.
cooling tower
a structure that regulates air temperature in a facility by using water to absorb heat from air conditioning systems
design case
the actual project design metrics that are compared to a baseline to show efficiency gains
drip irrigation
water delivered at low pressure directly to the roots of a plant
EPAct of 1992
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.
evapotranspiration
amount of water lost through evaporation in irrigation
full-time equivalent (FTE)
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.
graywater
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).
lavatory
aka bathroom sink
potable water
vs
not-potable water
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
reclaimed water
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.
submetering
the installation of submeters on water systems to allow buildings to track water usage trends, monitor fixture performance, and identify leaks
water closet
aka toilet
WaterSense
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
What is the water balance approach?
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.
What is the efficiency first approach?
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)
In the WE category rating system, a project obtains credits through its ability to reduce water use below a set _____.
baseline
The more a project reduces water use from baseline the more points will be awarded.
What is the design case in the WE category?
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.
What data is needed in order to calculate the daily water use? (2 things)
- maximum and minimum flow rates established by the EPAct of 1992
- number of building occupants & their average daily water fixture use
The full-time equivalent (FTE) is a calculation used in all rating systems for the ___, ___, and ___ categories.
WE, EA, and EQ
An occupant who is in the building for 8 hours a day receives an FTE of ___.
1.0
What are two ways to dispense water from a building?
flush fixtures and flow fixtures
Give examples of flush fixtures and flow fixtures.
How is water usage measured for each?
flush: toilets, urinals. measured per flush
flow: faucets, hoses, dishwashers. measured per minute (usually)
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 _____.
potable
graywater
What are the 3 types of water usage for the LEED BD+C rating system?
indoor, outdoor, and process water
What is the best way to reduce water use, regardless of the type of water use?
measuring or metering water use is the first+last strategy for each type of water usage.
According to EPA, about ____% of the total water used daily is used indoors.
70%
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)
20%
WE Prerequisite - Indoor Water Use Reduction requires projects be installed with high-performance flush & flow fixtures carrying the _____ label.
WaterSense.
It is an initiative created by EPA to promote water-saving products.
Ultra-low-flow water closets
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.
Dual-flush water closets
provides flush option for liquid waste and solid waste.
Ultra-low-flow urinals
urinal that uses reduced amount of water to flush liquid waste. Has an optimized valve that produced a pressure-assisted flush.
Low-flow aerators
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.
Waterless urinals
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.
Composting toilet
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%.
What climates commonly use harvested rainwater?
partially arid areas and other areas with limited water availability.
What are some standard precautions when utilizing graywater?
- backflow prevention
- limit the surface discharge of graywater.
WE Prerequisite - Building-Level Water Metering requires submeters to be ____ installed.
permanently
Installing submeters can reduce overall building water consumption by ___-___% in the first few months.
30-40%
WE Credit - Water Metering rewards a point to teams that install submeters on two or more of what kinds of applications?
- 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)
Process Water
water used for industrial purposes (ie boilers & cooling towers. For hospitality projects it could be dishwashers, laundry machines and ice machines)
closed-loop systems
water circulation system for industrial purposes that can reduce potable water; allow process water to be reused for many cycles.
Xeriscaping
landscaping desig that utilizes soil improvements, efficient irrigation, and native & adapted plant species to reduce water usage.
What is the most efficient form of irrigation?
drip irrigation. It is considered to be 90% water-efficient in contrast with traditional sprinklers.
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.
30%
9 billion!!!
What is the first step in using a nonpotable water source for irrigation?
capturing and collecting rainwater.
cisterns
large rainwater collection and storage tanks. usually used for commercial projects.
