ENV SP Water Conservation and Management 2 — Questions and Answers
Question 1: Under Envision credit RA1.2 – Protect Freshwater Resources, which practice is most effective at reducing non-point source pollution entering waterways?
- Installing deeper stormwater detention tanks
- Using vegetated buffers and bioretention areas (Correct answer)
- Increasing impervious surface area near water bodies
- Diverting all runoff to wastewater treatment plants
Correct answer: Using vegetated buffers and bioretention areas
Vegetated buffers and bioretention areas filter pollutants from runoff before it reaches streams and water bodies, directly protecting freshwater quality.
Question 2: What does 'stormwater runoff reduction' primarily achieve in urban infrastructure projects under the Envision framework?
- Faster evacuation of water from the watershed
- Reduced peak flows and decreased pollutant loads to receiving waters (Correct answer)
- Increased water consumption by the project
- Elimination of the need for detention ponds
Correct answer: Reduced peak flows and decreased pollutant loads to receiving waters
Reducing stormwater runoff lowers peak flow rates and pollutant loads to receiving water bodies, protecting aquatic ecosystems and downstream infrastructure.
Question 3: Which of the following is an example of green infrastructure used to manage stormwater on infrastructure projects?
- Concrete culverts with large diameter pipes
- Green roofs and permeable pavements (Correct answer)
- Conventional storm drain inlets with grates
- High-capacity underground cisterns without vegetation
Correct answer: Green roofs and permeable pavements
Green roofs and permeable pavements are green infrastructure approaches that retain and filter stormwater close to where it falls.
Question 4: The concept of 'water balance' in a sustainability assessment requires the project team to account for which of the following?
- Only rainfall amounts during construction
- All water inputs, outputs, and on-site storage over the project lifecycle (Correct answer)
- The cost of municipal water supply only
- Annual flood frequency statistics for the region
Correct answer: All water inputs, outputs, and on-site storage over the project lifecycle
A water balance accounts for all inputs (precipitation, municipal supply), outputs (evapotranspiration, discharge, consumption), and storage changes over time.
Question 5: In the Envision framework, why is protecting groundwater recharge areas important during infrastructure planning?
- Recharge areas are typically abandoned industrial sites
- Disrupting recharge areas can reduce long-term availability of groundwater supplies (Correct answer)
- Recharge areas have no ecological value
- Protecting recharge areas increases stormwater runoff
Correct answer: Disrupting recharge areas can reduce long-term availability of groundwater supplies
Groundwater recharge areas replenish aquifers; disrupting them with impervious surfaces reduces long-term freshwater availability for communities and ecosystems.
Question 6: Which water quality parameter is most commonly monitored to assess the effectiveness of stormwater best management practices (BMPs)?
- Air temperature adjacent to the water body
- Total suspended solids (TSS) in runoff (Correct answer)
- Noise levels near retention ponds
- Groundwater methane concentration
Correct answer: Total suspended solids (TSS) in runoff
Total suspended solids (TSS) is a key indicator of stormwater quality because BMPs are primarily designed to settle and filter particulates from runoff.
Question 7: How does reducing impervious surface coverage on a project site contribute to sustainable water management?
- It increases the speed of stormwater runoff
- It promotes infiltration, replenishing groundwater and reducing peak runoff (Correct answer)
- It eliminates the need for stormwater permits
- It increases water consumption by landscaping
Correct answer: It promotes infiltration, replenishing groundwater and reducing peak runoff
Less impervious surface allows more precipitation to infiltrate into the soil, recharging groundwater and reducing the volume and speed of stormwater runoff.
ENV SP Water Conservation and Management 2
Under Envision credit RA1.2 – Protect Freshwater Resources, which practice is most effective at reducing non-point source pollution entering waterways?