Chapter 05 - Water Efficiency Flashcards
What information would a project team need to successfully implement both rainwater management and outdoor water use reduction?
a) Water balance
b) Precipitation data
c) Occupancy counts
d) Location of indoor submeter
b) Precipitation data
The installation of water submeters in a building will provide the facility managers with the ability to do each of the following EXCEPT:
a) Pinpoint leaks
b) Track consumption
c) Determine fixture performance
d) Evaluate the quality of captures rainwater
d) Evaluate the quality of captured rainwater
In residential applications, which fixture uses the most water?
Showers
The addition or increasing the use of graywater in a building can help with:
Reduce potable water used by urinals and toilets
What can help reduce indoor potable water use?
a) Smaller kitchen sinks
b) Composting toilets
c) Stacking the building design
d) Gravity-based irrigation system
b) Composting toilets
All the following would be helpful in acquiring the water use reduction credit, except:
a) Planting more than half of the non-building-footprint site area in native vegetation
b) Rainwater collection
c) Low flow water closets
d) Low flow faucets
a) Planting more than half of the non-building-footprint site area in native vegetation
Water that is used for dish washing, clothes washing, and ice making is considered what type of water?
Process water
Harvesting rainwater can help with what project areas?
Reducing runoff
Who needs to be involved in design of a graywater system?
Architect
Plumbing Engineer
Civil Engineer
Local Agency
An owner is questioning the additional costs of submetering of a mixed-use project’s water systems. For what reason should the submeters be installed?
It identifies disparities between how a project’s water-based systems are designed to operate and how they actually perform
Project landscape plans for a previously developed site include avoiding disturbance of undeveloped areas and planting more than half of the non-building-footprint site area in non-moved native or adapted vegetation. A watercourse, drop structures, retention pond, and wetlands will also be developed with suitable native vegetation. To which three of the following LEED Credit might these design strategies contribute?
SS Credit: Rainwater management
SS Credit: Site Development-Protect or Restore Habitat
WE Credit: Outdoor Water Use Reduction
In commercial applications, which fixtures use the most water?
Water Closets
What type of water is rainwater?
Non-potable water
Indoor water use reductions require projections based on :
Occupants’ usage
Designers and builders can construct green buildings that significantly less municipal water than conventional construction by performing :
- Incorporating native landscaped that eliminate the need for irrigation
- Installing water-efficiency fixtures
- Using graywater and/or rainwater for non-potable water needs
Which are sources of graywater?
- Showers
- Washing machines
- Lavatory faucets
Occupants classified as FTEs are:
Full Time Equivalent : individuals who spend 40 hours a week (8h/day) in the project’s building.
during the Integrative process, which of the following improvements in water efficiency would most likely need to be researched to confirm that they are legal to implement within the project?
a) Site Conditions
b) Alternative water sources
c) Fixtures and fittings
d) Submetering
b) Alternative water sources
Which of the following reduces outdoor water use while also improving the triple bottom line?
Installing a landscape that doesn’t require a permanent irrigation system
In LEED which approach is taken in the Water Efficiency category to conserve water?
Efficiency first
What type of plants do the most to help reduce water use for landscaping?
Native plants
The baseline water use of a toilet is:
1.6 gpf (6 lpf)
What unit of measurement is used for toilets?
Gallons per flush ( Liters per flush)
All of the following would be helpful in acquiring the outdoor water use reduction credit, EXCEPT:
a) Macro-irrigation system
b) Drip irrigation system
c) Native Plants
d) Graywater collection system
a) Macro-irrigation system
If a developer is looking for water efficient appliances to install in residences what label should they look for on the appliances?
ENERGY STAR
What can help reduce indoor potable water?
Installing reduced-flow aerators on lavatory faucets
Which has the highest priority in LEED?
Indoor water use reduction
If a project owner wants to create a landscape with plants that require watering, which of the following is the minimum outdoor water reduction from baseline required for a new office project?
30%
Which is not a strategy for reducing potable water use for irrigation?
Installing building-level metering
Which are strategies for reducing potable water use for irrigation?
- Install smart-sensor technology
- Use treated wastewater
- Only use grass for play fields or other activities that required turf
Which are considered potable water?
- Water from a local well that meets EPA’s drinking water quality standards that is used for lavatory faucets.
What % of water is discharged to rivers, streams and other water bodies after use?
65%
How much potable water is used each day to flush toilets?
5 billion gallons of potable water
EPA stands for:
Environmental Protection Agengy (EPA)
Energy Policy Act mandates what?
The use of water-conserving plumbing fixtures to reduce water use in residential, commercial, and institutional buildings.
Water efficiency measures in commercial buildings can reduce water by:
30%
Non-potable water can be used for:
- landscape Irrigation
- Toilet and urinal flushing
- building systems
In buildings, the most significant savings associated with water efficiency result from:
Reduced energy costs. Energy is used to heat, cool, and distribute water within a building.
In commercial buildings, water heating accounts for: how much % of total energy use?
15%
What does CBECS stand for?
Commercial Building Energy Consumption Survey
How many points are possible under WE ?
11 points credit
3 pre-requisites
What does WE promotes?
Smarter use of water, inside and out, and water accountability to reduce potable water consumption
What is the first approach that LEED required for Energy Efficiency (EE) and Water Efficiency (WE) ?
Efficiency first approach
What is the intent of WE?
- Reduce water consumption
- Reuse water when appropriate, safe and legal
What are some renewable sources?
- Rain collection
Outdoor Water Use Reduction Prerequisite Requirements:
Option 1: No permanent irrigation required after 2 years
Option 2: Reduce at least 30% of baseline water consumption a month. Achieve this through planting species selection and irrigation system efficiency
Outdoor water use reduction prerequisites apply only to:
potable water
What is potable water?
- Water treated to drinking water standards
Potable water include:
- Municipal water supply
- Wells ( meets EPA’s drinking water standards)
What is non-potable water?
- Rainwater (cisterns)
- Water that does not meet drinking water standards
Outdoor water use reduction’s prerequisite strategies:
- Use Native and adaptive plants.
- Native also reduce runoffs
What is the intent of Outdoor water use reduction?
To reduce outdoor water consumption
Outdoor Water use reduction credit requirements:
Option 1: same as pre-requisite
Option 2: Reduce irrigation water demand by 50% or 100%. Counts non-potable sources
Outdoor water use reduction credit strategies:
- Minimize project’s water usage by installing a landscape that needs no irrigation (Xeriscaping)
- Reduce evapotranspiration for irrigation
What is Evapotranspiration?
The process by which water is transferred from the land to the atmosphere by evaporation from the soil and other surfaces and by transpiration from the plants
What is Black water?
Non-recyclable - water from toilets, urinals
- kitchen sink water- by local or state code
What is graywater?
- Untreated house-hold wastewater which has not come into contact with toilet waste or kitchen sinks
- Re-usable water for toilets, landscape irrigation
High efficiency irrigation strategies:
- Micro-irrigation: Drip irrigation
- Moisture Sensors
- Rain shut-offs
- Weather-based evapotranspiration controllers
Drip Irrigation system:
- Use 30%-50% less water than sprinkler irrigation
How do moisture and rain sensors work?
By ensuring that plants only receive water when necessary
What is a site assessment?
Includes a soil/climate analysis and will help determine appropriate plant material
Types of Synergies:
- Performing site assessment
- The use of native or adapted plants can mitigate climate conditions and reduce building energy consumption.
- Vegetation : solar shade, windbreak, muffle off-site noise
- Manage rainwater runoff
Native plants can:
Restore habitat for wildlife
Responsible parties for Outdoor Water Use Reduction:
Landscape Architect
Ecologist
Plumbing Engineer
What type of water on a residential condominium project could not be used to qualify for C-Outdoor Water Use Reduction?
Black Water
To implement efficient landscape irrigation for C-Outdoor Water Use Reduction, What type of irrigation systems can be used?
- Recycled system
- Micro-irrigation system
- Treated system
The following landscape factors must be used to quantify the water savings for water efficient landscaping (Kl):
- Species Factor
- Micro-climate Factor
- Density Factor
Landscape designs that aim to eliminate the need for irrigation are:
Xeriscape
Indoor Water Use Reduction Prerequisites:
- Reduce water use by 20% from baseline
- All new fixtures must be WaterSense labeled
- Meet minimum water efficiency for appliances, equipment, and processes
- Applies only to potable water
What is WaterSense?
It is an EPA certification awarded to fixtures that use less water than comparable fixtures.
What is ENERGYSTAR?
an EPA/DOE program which provides certification to buildings and consumer products which meet certain standards of energy efficiency
WaterSense labels apply only to:
Lavatory faucets, toilets, urinals, showerheads
Indoor Water Use Reduction strategies:
- To focus in the 20% of items that will affect the 80% of the costs for reduction application
- Reuse of stormwater and graywater for non-potable applications
- Watersense fixtures
- For existing plumbing fixtures: installing new low flow aerators and installing new flush valves
What is the baseline to calculate water use reductions?
Occupant’s usage
Regulated water is:
Calculated for plumbing fixtures that are regulated by Energy policy act (lavatory and kitchen faucets, urinals, toilets, and showerheads)
Non-regulated or process water is:
Water that is used for industrial processes and building systems and operational processes
Types of non-regulated or process water:
Cooling towers, boilers, chillers, dishwashing, clothing washing, ice making water
Indoor Water Use Reduction (IWUR) requirements:
- Reduce water use by 25% - 50% from baseline
- Additional potable water savings from alternative water sources
- Meet additional water efficiency for appliances, equipment, and processes
IWUR calculations:
Reduction = Design case/baseline case
IWUR radditional requirements for healthcare, retail, schools, and hospitality:
-Install water efficient commercial equipment
Water efficient commercial equipment:
Dishwashers, food steamers, combination ovens, discharge water temperature tempering, venturi-type flow-through vacuum generator or aspirators
Types of WaterSense fixtures:
- Ultra-low flow
- Pressure-assisted
- Composting toilets
- Waterless urinal
Composing toilets:
is a fry plumbing fixture that contains and treat human waste via microbiological processes. They are not practical for many applications, such as high-rise buildings
Do alternative water sources count as prerequisites for IWUR?
No, but can contribute for the credit beyond the first 20%
Responsible parties for IWUR:
- Plumbing Engineer
- Civil Engineer
- Architect
What is the main standard used to define the baseline per flush and flow rates for the water efficiency of fixtures used in the interior of the building?
Energy Policy Act (EP Act) of 1992
What is the intent of Building-Level Water Metering (BLWM)?
To support water management and identify opportunities for additional water savings by tracking water consumption
Building-Level Water Metering prerequisite:
Tracl (and share with USGBC) monthly and annual water usage data for 5 years
Building-Level Water Metering credit requirements:
- Install additional metering for two or more:
Irrigation systems, Indoor plumbing, domestic hot water, large boilers, reclaimed water, other process water
LEED - Healthcare (HC) added requirements:
Install water meters on any 5 of the following:
Purified water systems, filter backwash water, water use in dietary department, water use for laundry, laboratory water use, water used in central sterile and processing dept., water use in physiotherapy and hydrotherapy and treatment areas, Waster use in physiotherapy and hydrotherapy and treatment areas, water use in surgical suite, closed-loop hydronic system makeup water, cold water makeup for domestic hot water systerms
BLWM strategies and terms:
- Sub-metering identifies disparities between how a project’s water-based systems are designed to operate and how they actually perform
- Sub-meters will enable facility managers to pinpoint leaks, track consumption, and determine fixture performance
- Water meters can be external meters ( measure from outside the pipe) or wet meter (from inside the pipe)
- Ongoing metering allows building operators to better gauge a building water performance and identify problems early
BLWM responsible parties:
Plumbing engineer
building manager
owner
LEED projects are requited to share whole-project water usage data for how long?
5 years or until the building changes ownership
Cooling Tower Water Use intent:
To conserve water use for cooling tower makeup while controlling microbes, corrosion, and scale in the condenser water system
Cooling Tower water use key points:
- Evaporation of cooling tower water leads to build up of dissolved solids
- Makeup water is the added water to the cooling tower system or evaporative condenser to offset water lost due to evaporation and other causes
- Blowdown is the process of discharging cooling tower water to remove dissolved solids
- Increasing the # of cycles between blowdown reduces the amount of makeup water inputs
CTWU requirements:
- conduct a one-time potable water analysis, measuring at least the 5 control parameters
- Calculate the # of cooling tower cycles
- Limit cooling tower cycles to avoid exceeding max. values for any of these parameters
of cooling tower cycles:
max. allowed concentration level of each parameter/actual concentration level of each parameter
CTWU strategies:
Non-potable sources should contain low levels of dissolved solids. AC condensate, rainwater, steam systems, food steamer discharge water, fire pump test water, and ice machine condensate
CTWU responsible parties:
Mechanical engineer
Plumbing engineer
Water is periodically discharged from cooling towers as blowndown. Why is this necessary?
To reduce concentrations of dissolved solids
