1: What is another name for rain gardens used to increase rain runoff absorption?
A: Bioretention facilities
B: Sedimentation basins
C: Thermal retention units
D: Erosion control zones
Correct Answer: A
Explanation: Rain gardens are also called bioretention facilities designed to increase rain runoff absorption by the soil.
2: Which of the following helps in filtering pollutants in rain gardens?
A: Plastic liners
B: Plants and soil medium
C: Concrete slabs
D: Metal grates
Correct Answer: B
Explanation: Rain gardens use plants and natural or engineered soil mediums to filter pollutants carried by urban runoff.
3: How can rain gardens help to mitigate the heat-island effect in urban areas?
A: By reflecting sunlight
B: Through ambient air and water temperature decrease
C: By absorbing carbon dioxide
D: Through producing shade for buildings
Correct Answer: B
Explanation: Rain gardens reduce ambient air and water temperature, which helps mitigate the heat-island effect in urban areas.
4: Which type of vegetation is commonly found in rain gardens?
A: Cacti
B: Wetland edge vegetation
C: Alpine tundra plants
D: Desert shrubs
Correct Answer: B
Explanation: Rain gardens commonly include wetland edge vegetation like wildflowers, sedges, rushes, and small trees.
5: What role do deep plant roots in rain gardens play?
A: They prevent soil compaction
B: They enhance water infiltration
C: They provide moisture redistribution
D: All of the above
Correct Answer: D
Explanation: Deep plant roots enhance infiltration, maintain soil permeability, and provide moisture redistribution.
6: What process helps plants release water vapor back to the atmosphere in rain gardens?
A: Photosynthesis
B: Transpiration
C: Evaporation
D: Absorption
Correct Answer: B
Explanation: Plants release water vapor back to the atmosphere through the process of transpiration.
7: Rain gardens improve water quality by filtering:
A: Soil particles
B: Rainfall acidity
C: Organic pollutants
D: Runoff
Correct Answer: D
Explanation: Rain gardens improve water quality by filtering runoff.
8: The first residential rain gardens were developed in which US state?
A: California
B: Texas
C: Maryland
D: Florida
Correct Answer: C
Explanation: The first residential rain gardens were developed in Maryland in 1990.
9: What type of tool are rain gardens recognized as in stormwater management practices?
A: High-Impact Design tool
B: Low-Impact Development tool
C: Erosion Control tool
D: Urban Heat Management tool
Correct Answer: B
Explanation: Rain gardens are recognized as a significant Low Impact Development (LID) tool.
10: What is the primary function of bioswales in stormwater management?
A: To slope to a destination
B: To filter air pollutants
C: To provide habitat for wildlife
D: To beautify urban areas
Correct Answer: A
Explanation: Bioswales are vegetated roadside swales that slope to a destination to manage stormwater.
11: Redirected stormwater is typically:
A: Cooler than groundwater
B: Hotter than groundwater
C: The same temperature as groundwater
D: Irrelevant to water temperature
Correct Answer: B
Explanation: Redirected stormwater is often warmer than groundwater, impacting aquatic ecosystems.
12: Why is urban runoff problematic for aquatic ecosystems?
A: It increases biodiversity
B: It reduces dissolved oxygen levels
C: It cleans the water
D: It increases water temperature
Correct Answer: B
Explanation: Urban runoff can reduce dissolved oxygen levels, upsetting aquatic ecosystems.
13: What is a key pollutant often found in urban runoff?
A: Carbon monoxide
B: Nitrogen gas
C: Volatile organic compounds
D: Oxygen
Correct Answer: C
Explanation: Volatile organic compounds are among the pollutants often found in urban runoff.
14: Stormwater management on a watershed scale prevents:
A: Plant growth
B: Downstream impacts
C: Soil formation
D: Heat islands
Correct Answer: B
Explanation: Stormwater management on a watershed scale aims to prevent downstream impacts on urban water quality.
15: Rain gardens contribute to urban runoff mitigation by:
A: Increasing water temperature
B: Filtering and retaining stormwater on-site
C: Diverting water to sewers
D: Reducing plant growth
Correct Answer: B
Explanation: Rain gardens filter and retain stormwater on-site, reducing urban runoff.
16: An integrated approach to bioretention is vital for:
A: Preventing urban heat
B: Enhancing rainfall rates
C: Managing water quality and quantity
D: Increasing runoff volume
Correct Answer: C
Explanation: An integrated approach, called the stormwater chain, manages water quality and quantity through bioretention.
17: What is the term for the sequence incorporating all stormwater control techniques?
A: Water cycle
B: Stormwater chain
C: Rainfall grid
D: Hydration loop
Correct Answer: B
Explanation: The “stormwater chain” consists of all techniques to prevent runoff, retain, detain, and convey rainfall.
18: What is a primary environmental benefit of bioretention?
A: Increased energy consumption
B: Enhanced urban sprawl
C: Reduced pollution and increased wildlife diversity
D: Increased impermeable surfaces
Correct Answer: C
Explanation: Bioretention sites contribute to reducing pollution and increasing wildlife diversity.
19: Which process involves the downward movement of water through soil?
A: Evaporation
B: Infiltration
C: Transpiration
D: Percolation
Correct Answer: B
Explanation: Infiltration is the process of water moving downward through the soil.
20: What natural process is mimicked by rain gardens to control stormwater quantity?
A: Evapotranspiration
B: Biodegradation
C: Photosynthesis
D: Filtration
Correct Answer: A
Explanation: Rain gardens mimic evapotranspiration to control stormwater quantity.
21: What happens when water pools on top of a bioretention feature?
A: Rapid runoff occurs
B: Particles settle out
C: Soil compacts
D: Water heats up
Correct Answer: B
Explanation: When water pools on top, suspended solids and particles settle out.
22: Plants in rain gardens help to:
A: Increase soil compaction
B: Absorb toxins
C: Speed water flow
D: Reduce soil moisture
Correct Answer: B
Explanation: Plants absorb and take up nutrients and water through their roots in rain gardens.
23: Optimally designed rain gardens have what kind of water storage capacity?
A: Maximum
B: Minimal
C: Average
D: None
Correct Answer: A
Explanation: Rain gardens should be optimally designed for maximum water storage capacity.
24: Bioswales and rain gardens are often confused, but bioswales:
A: Are level
B: Slope to a destination
C: Require no vegetation
D: Collect rainwater
Correct Answer: B
Explanation: Unlike level rain gardens, bioswales slope to a destination.
25: Which type of soil component is 20% in the bioretention soil mixture of rain gardens?
A: Sand
B: Compost
C: Clay
D: Silt
Correct Answer: B
Explanation: The bioretention soil mixture typically contains 20% compost.
26: Rain garden plants need to tolerate:
A: Only dry conditions
B: Only wet conditions
C: Both dry and wet conditions
D: Only cold conditions
Correct Answer: C
Explanation: Rain garden plants must tolerate both wet and dry soil conditions.
27: Why are native plants often chosen for rain gardens?
A: They require more water
B: They are more tolerant to local conditions
C: They grow food crops
D: They need less sunlight
Correct Answer: B
Explanation: Native plants are more tolerant of the local climate, soil, and water conditions.
28: What type of plants perform best in rain gardens?
A: Plants with superficial roots
B: Plants tolerant to saturated and dry conditions
C: Plants with low growth rate
D: Plants requiring heavy maintenance
Correct Answer: B
Explanation: Plants that tolerate both saturated and dry soil conditions perform best in rain gardens.
29: What is phytoremediation in rain gardens?
A: Soil erosion
B: Natural removal of pollutants by plants
C: Solid particle settlement
D: Runoff diversion
Correct Answer: B
Explanation: Phytoremediation involves plants naturally removing pollutants from stormwater.
30: Which country plans to implement “sponge cities” to prioritize natural stormwater management?
A: Japan
B: China
C: India
D: Russia
Correct Answer: B
Explanation: China plans to develop “sponge cities” to manage stormwater through natural means like rain gardens and green roofs.
31: What is the impact of adding diverse plantings to existing gardens for rain garden adaptation?
A: Decreased water filtration
B: Increased infiltration capacity
C: Reduced soil moisture
D: More runoff generation
Correct Answer: B
Explanation: Adding diverse plantings increases the infiltration capacity of adapted rain gardens.
32: How is stormwater quality controlled by bioretention?
A: Through increased urban runoff
B: By filtration and decomposition
C: By removing storm drains
D: Through accelerating capillary action
Correct Answer: B
Explanation: Stormwater quality is controlled by bioretention through filtration, adsorption, degradation, and decomposition.
33: Which of the following is a benefit of rain garden installations on public infrastructure?
A: Increased peak water discharge
B: Temporary water logging
C: Reduced load on conventional stormwater systems
D: Increased urban heat
Correct Answer: C
Explanation: Rain gardens reduce the load on conventional stormwater systems and manage excess runoff.
34: What is the function of a French drain in a rain garden system?
A: To plant trees
B: To direct water overflow
C: To increase stormwater storage
D: To prevent soil erosion
Correct Answer: B
Explanation: A French drain helps to direct excess water overflow to another location.
35: How do rain gardens affect groundwater recharge?
A: They prevent it
B: They reduce it
C: They enhance it
D: They have no effect
Correct Answer: C
Explanation: Rain gardens enhance groundwater recharge by increasing infiltration.
36: What type of drainage system did the SEA Street project in Seattle use to manage stormwater?
A: Concrete channels
B: Linear wetlands
C: Rain gardens
D: Water tanks
Correct Answer: C
Explanation: SEA Street used an innovative rain garden system to manage stormwater.
37: How much stormwater reduction was achieved by Maplewood, Minnesota’s rain garden installations?
A: 20%
B: 45%
C: 60%
D: 99%
Correct Answer: D
Explanation: The SEA Street project resulted in a 99% reduction in stormwater outflow.
38: What is a key lesson from the University of Maryland regarding rain gardens?
A: They are ineffective in all conditions
B: They significantly improve water clarity
C: They increase soil compaction
D: They cause more erosion
Correct Answer: B
Explanation: Research at the University of Maryland showed rain gardens significantly improve water clarity.
39: Which of the following is vital in the effectiveness of rain gardens in clay soils?
A: The type of plants used
B: Pre-installation infiltration rates
C: Soil color
D: Water temperature
Correct Answer: B
Explanation: Pre-installation infiltration rates are crucial for the effectiveness of rain gardens in clay soils.
40: Rain gardens in Xi’an, China, could handle how many large storm events without overflow in four years?
A: 5
B: 15
C: 23
D: 28
Correct Answer: C
Explanation: Rain gardens in Xi’an retained rainfall from most storms and only overflowed during 5 out of 28 events.
41: Which organization runs the 12,000 Rain Garden campaign for Puget Sound?
A: Environmental Protection Agency
B: University of Washington
C: Local landscape contractors
D: A coordinated public initiative
Correct Answer: D
Explanation: The 12,000 Rain Garden campaign for Puget Sound is a coordinated public initiative aimed at water quality improvement.
42: What role do trees and shrubs play in larger bioretention sites?
A: They only provide aesthetic value
B: They help cover larger bioretention areas
C: They consume more water than herbs
D: They reduce garden functionality
Correct Answer: B
Explanation: Trees and shrubs are used in rain gardens to cover larger bioretention areas.
43: What program did Portland, Oregon establish to reduce loads on its combined sewer system?
A: Clean River Rewards
B: Flood Management Scheme
C: Portland Hydration Plan
D: Urban Soil Protection Initiative
Correct Answer: A
Explanation: Portland’s Clean River Rewards program encourages residents to create rain gardens and reduce sewer loads.
44: Which academic group installed rain gardens in Washtenaw County for educational purposes?
A: Local high schools
B: University students
C: Municipal staff
D: Professional landscape architects
Correct Answer: B
Explanation: University students are involved in designing rain gardens in Washtenaw County for educational and practical purposes.
45: Rain gardens perform best when they:
A: Are left without any plantings
B: Interact with the greater stormwater control system
C: Do not capture runoff
D: Use artificial materials only
Correct Answer: B
Explanation: Rain gardens function effectively when they interact with a broader stormwater control system integrated approach.
46: What material in rain garden soil mixtures is most effective for pollutant filtration?
A: Sand
B: Compost
C: Clay
D: Silt
Correct Answer: B
Explanation: Soils with higher concentrations of compost have shown improved effects on filtering pollutants.
47: Which state created a residential focus group for rain garden adoption published as a planning resource?
A: Oregon
B: Minnesota
C: California
D: Florida
Correct Answer: B
Explanation: Maplewood, Minnesota, created a residential focus group to guide rain garden project planning.
48: Why is maintaining diverse rain garden plantings important across climates?
A: To maintain water retention material
B: To offer year-round garden functionality
C: To attract pests and insects
D: To provide purely aesthetic gardens
Correct Answer: B
Explanation: Diverse plantings ensure the rain garden remains functional in different climatic conditions throughout the year.
49: Which mitigation program started in Queensland in 2005 supports rain garden adoption?
A: Save Our Streams
B: Water By Design
C: Flood Guardians
D: Green Roof Initiative
Correct Answer: B
Explanation: The Water By Design program supports the adoption of rain gardens and other sustainable urban designs in Queensland.
50: What is the main goal of the rain garden installation initiative in Kansas City, Missouri?
A: To create employment opportunities
B: To promote recreational activities
C: To establish 10,000 individual rain gardens
D: To reduce property values
Correct Answer: C
Explanation: Kansas City’s initiative aims to establish 10,000 individual rain gardens to manage stormwater.
51: In which state did Homeowners Building Associations collaborate to install rain gardens for stormwater management?
A: Delaware
B: New Jersey
C: Michigan
D: Maryland
Correct Answer: C
Explanation: Homeowners in Michigan collaborated to install rain gardens to improve watershed quality.
52: What material is used specifically in bioretention cells to aid rain garden facility performance?
A: Synthetic filters
B: Gravel layers
C: Smooth concrete
D: Rubber mats
Correct Answer: B
Explanation: Gravel layers are utilized in bioretention cells to support rain garden performance.
53: Implementing rain gardens helps to:
A: Increase groundwater contamination
B: Facilitate groundwater recharge
C: Erode urban surfaces
D: Elevate urban heat islands
Correct Answer: B
Explanation: Rain gardens facilitate groundwater recharge by promoting infiltration and reducing runoff.
54: What was the observed reduction of stormwater volume in the Seattle SEA Street project?
A: 1%
B: 25%
C: 55%
D: 99%
Correct Answer: D
Explanation: The SEA Street project observed a 99% reduction in stormwater volume due to rain garden implementation.
55: Rain gardens significantly capture the initial stormwater flow to:
A: Increase erosion rates
B: Directly dump into waterways
C: Filter contaminants
D: Create standing water
Correct Answer: C
Explanation: Rain gardens capture the initial stormwater flow to effectively filter various contaminants.
56: Which group benefits from optimized bioretention through rain gardens in urban areas?
A: Only plant species
B: Urban wildlife and biodiversity
C: Manufacturing units
D: Combustion engine vehicles
Correct Answer: B
Explanation: Rain gardens enhance urban wildlife and biodiversity by providing carefully designed bioretention systems.
57: What role do soil microorganisms play in rain gardens?
A: Increase evaporation rates
B: Break down pollutants
C: Block water channels
D: Add to soil compaction
Correct Answer: B
Explanation: Soil microorganisms effectively break down organic pollutants and enhance soil quality.
58: What typical and cost-effective drainage feature is used in Australia’s rain gardens?
A: Concrete trenches
B: Natural swales
C: Synthetic covers
D: Terraced gardens
Correct Answer: B
Explanation: Natural swales are often employed in rain gardens for cost-effective stormwater management in Australia.
59: Why is pre-installation soil testing critical for effective rain garden functioning?
A: To assess plant growth patterns
B: To determine pre-existing infiltration rates
C: To identify underground wires
D: To measure urban heat levels
Correct Answer: B
Explanation: Pre-installation soil testing helps determine existing infiltration rates which are crucial for effective rain garden design.
60: How can rain gardens improve the sustainability of urban environments?
A: By promoting high impervious areas
B: By increasing natural habitats and reducing stormwater loads
C: By reducing soil moisture permanently
D: By preventing all rainfall from reaching groundwater
Correct Answer: B
Explanation: Rain gardens improve sustainability by enhancing natural habitats and reducing stormwater loads in urban setups.