Water Efficiency Flashcards
Water efficiency in commercial buildings can easily reduce water usage by ___% or more.
30%
______ water is used for building systems such as cooling towers, boilers and chillers
Process
_____ water comes from bathtubs, bathroom wash basins, & clothes washers.
gray water
Water from kitchen sinks and dishwashers is considered ________ water
black water
Water from ____ and _____ is always considered black water
Toilets and urinals
What are three common sources of Non-Potable water?
Household gray water (untreated)
Captured rainwater
Non-potable treated by public agency
What are two uses of Non-Potable water?
Irrigation and Toilet/Urinal Water
Name two states that ban the capture or use of rainwater?
Colorado and Nevada (Las Vegas)
What is the prerequisite for Water Use Reduction?
Reduce by 20%
What is the reference authority for Water Reduction?
Energy Policy Act (EPAct) 1992
What are four examples of non-regulated fixtures?
Washing machines, dishwashers, irrigation, process water
What are three factors that do NOT change when calculating Water Reduction?
FTE, Number of Fixtures, Number of uses/day
The two options for reducing potable water use for irrigation?
Option 1 (2 points) Reduce potable water use by 50%. (Use 50% gray water) Option 2 (4 points) Reduce potable water use by 100% AND reduce total water by 50%. (Use gray water and cut use by 50%)
What are the two plant species factors?
Herbaceous Perennials (Drought tolerant plants) and Xeriscaping (Dry-Scaping; landscape design that minimizes water use)
What are four stategies for Water Efficient Landscaping?
Plant species factor or selection, Plant Density Factor, Irrigation Efficiency, Non-Potable Water Reuse.
What is evapotranspiration?
Loss of water by evaporation from soil and transpiration from plants
What is “Reference Evapotranspiration Rate” (ET0)?
Amount of water necessary to grow a reference plant
What is “Landscape Coefficient”
The volume of water loss via evapotranspiration. (dependent on species, density & climate)
Landscape Coefficient (Kl) is equal to what?
(Ks) Species x (Kd) Density x (Kmc) Microclimate (McDs)
ETO = Regional Evapotranspiration and stays constant)
What are four Water Efficient Landscaping factors that change in Base Case and Design Case?
Density, Species, Irrigation Efficiency, Potable Water Use & Non-Potable Water Use
What are two Water Efficient Landscaping factors that do NOT change in Base Case and Design Case?
Microclimate factor and Reference Evapotranspiration Rate
What is the intent of Innovative Wastewater Technology?
To reduce wastewater and potable water demand
What are two “Innovative” options for reducing wastewater and potable water demand? (Worth 2 credits)
1- Reduce potable water used for toilets by 50% (EP 100%) by conservation or by using non-potable water.
2- Treat 50% (EP 100%) of wastewater on site to tertiary standards
What is the EPAct 1992 max allowable flow rate for toilets? Rate for Urinals?
1.6 gpf toilets, 1.0 gpf urinals
What are the low flow gpf rates for toilets and urinals?
Dual flush 1.6 gpf/.8 gpf for toilets and .5 gpf for urinals or 0 for waterless urinals.
What are the 3 factors that change between the base case and design case for water use calcs?
Gray water use, Plumbing fixture consumption (EPAct 1992 vs Actual) and Water Treatment
What are the 3 factors that do NOT change between the base case and design case for water use calcs?
FTE, number of plumbing fixtures & number of bathroom trips per day.
What is the prerequisite percent reduction of water use?
20%
What is the water use percent reduction required for EP?
45%
What is the water use percent reduction required for 2 points, 3 points and 4 points?
30%. 35%, 40%
How many urinal/toilet flushes per day for men? Women?
2 Urinal + 1 Toilet for Men. 3 toilet for women
How do you calculate the Local Evapotranspiration Rate? (ETl)
Kl x ETo = ETl (Landscape Coefficient x Reference Evapotranspiration Rate = Local Evapotranspiration Rate)
For Process Water Reduction (Schools Only) what are 3 requirements?
1- No refrigeration equipment that uses water for cooling.
2- No garbage disposals
3- Must use 4 process equipment items that reduce water use 20%
What are 4 examples of equipment that reduce process water>
Clothes washer - 7.5g/ft3 per cycle Dishwahers - 1g per rack Ice Mach - > 175 lbs/day 20g per 100lbs Ice Mach - < 175 lbs/day 30g per 100lbs Food Steamers - 2g per hour Pre-rince spray valves - 1.4 g per min
For EP on Process Water, what % water savings?
40%
