LEED (Leadership in Energy and Environmental Design Certification) Water Efficiency 5 — Questions and Answers
Question 1: A landscaping design uses only native and adaptive plants with no permanent irrigation system. Which LEED pathway does this approach satisfy?
- Option 1: Reduce by 30%
- Option 2: No irrigation required (Correct answer)
- Option 3: Rainwater reuse
- Option 4: Smart irrigation controllers
Correct answer: Option 2: No irrigation required
LEED's Outdoor Water Use Reduction credit includes an option for projects that require no permanent irrigation after an establishment period, using native or adaptive plants.
Question 2: Which LEED rating system does NOT include a standalone Outdoor Water Use Reduction credit because outdoor water use is not applicable?
- BD+C: New Construction
- BD+C: Core and Shell
- ID+C: Commercial Interiors (Correct answer)
- BD+C: Healthcare
Correct answer: ID+C: Commercial Interiors
LEED ID+C: Commercial Interiors does not include an Outdoor Water Use Reduction credit because tenant fit-out projects typically have no control over exterior landscaping.
Question 3: What does 'makeup water' refer to in the context of cooling tower operations under LEED?
- Water added to replace losses from evaporation, drift, and blowdown (Correct answer)
- Water used to clean cooling tower surfaces
- Water stored in the cooling tower basin as backup
- Water recycled from the chiller condenser loop
Correct answer: Water added to replace losses from evaporation, drift, and blowdown
Makeup water replenishes the water lost from a cooling tower through evaporation, drift (misting), and intentional blowdown to control mineral concentration.
Question 4: A LEED project team wants to reduce water use in their medical sterilization equipment. Under which credit category should they document this reduction?
- Outdoor Water Use Reduction
- Cooling Tower Water Management
- Indoor Water Use Reduction – Process Water (Correct answer)
- Water Metering
Correct answer: Indoor Water Use Reduction – Process Water
Water used in medical sterilization equipment is classified as process water, and its reduction is documented under the process water component of the Indoor Water Use Reduction credit.
Question 5: What is the primary reason LEED requires 'cycles of concentration' management in cooling towers?
- To improve heat transfer efficiency
- To reduce the frequency of blowdown and conserve water (Correct answer)
- To lower electricity consumption of cooling tower fans
- To prevent Legionella bacteria growth
Correct answer: To reduce the frequency of blowdown and conserve water
Managing cycles of concentration (the ratio of dissolved solids in blowdown vs. makeup water) reduces the frequency of blowdown, directly conserving water in cooling tower operations.
Question 6: Under LEED v4 BD+C, which of the following best describes a 'transient occupant' for the purpose of water use calculations?
- A full-time employee who works 40 hours per week
- A visitor or customer who spends less than a full workday in the building (Correct answer)
- A part-time worker scheduled for 20 hours per week
- An overnight guest at a hotel
Correct answer: A visitor or customer who spends less than a full workday in the building
Transient occupants are visitors or customers who spend less than a full working day in the building and are assigned a lower water use factor than full-time equivalent (FTE) occupants.
Question 7: Which US EPA program's WaterSense label is referenced by LEED as a benchmark for high-efficiency plumbing fixtures?
- ENERGY STAR
- WaterSense (Correct answer)
- GreenStar
- Demand Side Management
Correct answer: WaterSense
EPA WaterSense is the federal labeling program that certifies high-efficiency water fixtures, and LEED references WaterSense specifications as a benchmark for fixture performance.
LEED (Leadership in Energy and Environmental Design Certification) Water Efficiency 5
A landscaping design uses only native and adaptive plants with no permanent irrigation system.
Which LEED pathway does this approach satisfy?