WRM3701 Practice Questions and Correct Verified
Answers 2026
Question 1:
In a catchment experiencing increasing urbanization, which hydrological response is
most likely to occur during a high-intensity rainfall event?
A) Increased infiltration and reduced peak discharge
B) Reduced surface runoff and delayed hydrograph peak
C) Increased peak discharge and shorter lag time
D) Decreased rainfall intensity and increased evapotranspiration
Correct Answer: C
Rationale: Urbanization increases impervious surfaces like roads and buildings, which
reduces infiltration and accelerates surface runoff. This leads to a faster concentration of
flow in rivers, resulting in a higher peak discharge and a shorter lag time between the
rainfall and the peak flow .
Question 2:
A watershed experiences increased urbanization, resulting in higher peak runoff and
reduced groundwater recharge. Which hydrological change best explains this outcome?
A) Increased infiltration due to vegetation growth
B) Decreased surface imperviousness
C) Increased impervious surfaces reducing infiltration
D) Increased evapotranspiration from soil moisture
Correct Answer: C
Rationale: The primary effect of urbanization is the creation of impervious surfaces such
,as roads and buildings. These surfaces prevent water from infiltrating into the soil, which
increases surface runoff and decreases groundwater recharge .
Question 3:
Which component of the hydrological cycle directly transfers water from vegetation
back into the atmosphere?
A) Condensation
B) Evapotranspiration
C) Infiltration
D) Percolation
Correct Answer: B
Rationale: Evapotranspiration is the combined process of evaporation from the soil and
transpiration from plants. It is the primary mechanism by which water is returned to the
atmosphere from vegetation .
Question 4:
A river system shows increased sediment load after deforestation. What is the primary
cause?
A) Reduced precipitation intensity
B) Increased soil stability
C) Loss of root structures binding soil
D) Increased groundwater recharge
Correct Answer: C
Rationale: The root systems of trees and plants bind the soil together, preventing
,erosion. Deforestation removes this protective structure, making the soil more
susceptible to erosion and increasing the sediment load in nearby rivers .
Question 5:
Which factor most directly affects groundwater recharge rates?
A) Atmospheric pressure only
B) Soil permeability
C) Wind speed
D) Solar radiation intensity
Correct Answer: B
Rationale: Groundwater recharge is the process of water infiltrating through the soil
and percolating down to the water table. Soil permeability, or the ability of water to pass
through the soil, is the most direct factor influencing this rate .
Question 6:
Which parameter is the best indicator of organic pollution in surface water?
A) Dissolved oxygen (DO)
B) Water hardness
C) Electrical conductivity only
D) pH stability
Correct Answer: A
Rationale: Organic pollution consumes dissolved oxygen in water as microorganisms
break it down. Therefore, a low dissolved oxygen level is a strong indicator of organic
pollution. pH and hardness are indicators of other water quality parameters .
, Question 7:
In wastewater treatment, primary treatment is designed primarily to:
A) Remove dissolved salts
B) Remove suspended solids
C) Eliminate pathogens completely
D) Increase dissolved oxygen
Correct Answer: B
Rationale: Primary treatment is a physical process that involves sedimentation to
remove settleable organic and inorganic solids from wastewater .
Question 8:
Which parameter is the best indicator of organic pollution in surface water?
A) Dissolved oxygen (DO)
B) Water hardness
C) Electrical conductivity only
D) pH stability
Correct Answer: A
Rationale: Low dissolved oxygen levels are a direct indicator of organic pollution, as the
decomposition of organic matter consumes oxygen. The other options are not specific
indicators of this type of pollution .
Question 9:
A water utility uses chlorination primarily to:
Answers 2026
Question 1:
In a catchment experiencing increasing urbanization, which hydrological response is
most likely to occur during a high-intensity rainfall event?
A) Increased infiltration and reduced peak discharge
B) Reduced surface runoff and delayed hydrograph peak
C) Increased peak discharge and shorter lag time
D) Decreased rainfall intensity and increased evapotranspiration
Correct Answer: C
Rationale: Urbanization increases impervious surfaces like roads and buildings, which
reduces infiltration and accelerates surface runoff. This leads to a faster concentration of
flow in rivers, resulting in a higher peak discharge and a shorter lag time between the
rainfall and the peak flow .
Question 2:
A watershed experiences increased urbanization, resulting in higher peak runoff and
reduced groundwater recharge. Which hydrological change best explains this outcome?
A) Increased infiltration due to vegetation growth
B) Decreased surface imperviousness
C) Increased impervious surfaces reducing infiltration
D) Increased evapotranspiration from soil moisture
Correct Answer: C
Rationale: The primary effect of urbanization is the creation of impervious surfaces such
,as roads and buildings. These surfaces prevent water from infiltrating into the soil, which
increases surface runoff and decreases groundwater recharge .
Question 3:
Which component of the hydrological cycle directly transfers water from vegetation
back into the atmosphere?
A) Condensation
B) Evapotranspiration
C) Infiltration
D) Percolation
Correct Answer: B
Rationale: Evapotranspiration is the combined process of evaporation from the soil and
transpiration from plants. It is the primary mechanism by which water is returned to the
atmosphere from vegetation .
Question 4:
A river system shows increased sediment load after deforestation. What is the primary
cause?
A) Reduced precipitation intensity
B) Increased soil stability
C) Loss of root structures binding soil
D) Increased groundwater recharge
Correct Answer: C
Rationale: The root systems of trees and plants bind the soil together, preventing
,erosion. Deforestation removes this protective structure, making the soil more
susceptible to erosion and increasing the sediment load in nearby rivers .
Question 5:
Which factor most directly affects groundwater recharge rates?
A) Atmospheric pressure only
B) Soil permeability
C) Wind speed
D) Solar radiation intensity
Correct Answer: B
Rationale: Groundwater recharge is the process of water infiltrating through the soil
and percolating down to the water table. Soil permeability, or the ability of water to pass
through the soil, is the most direct factor influencing this rate .
Question 6:
Which parameter is the best indicator of organic pollution in surface water?
A) Dissolved oxygen (DO)
B) Water hardness
C) Electrical conductivity only
D) pH stability
Correct Answer: A
Rationale: Organic pollution consumes dissolved oxygen in water as microorganisms
break it down. Therefore, a low dissolved oxygen level is a strong indicator of organic
pollution. pH and hardness are indicators of other water quality parameters .
, Question 7:
In wastewater treatment, primary treatment is designed primarily to:
A) Remove dissolved salts
B) Remove suspended solids
C) Eliminate pathogens completely
D) Increase dissolved oxygen
Correct Answer: B
Rationale: Primary treatment is a physical process that involves sedimentation to
remove settleable organic and inorganic solids from wastewater .
Question 8:
Which parameter is the best indicator of organic pollution in surface water?
A) Dissolved oxygen (DO)
B) Water hardness
C) Electrical conductivity only
D) pH stability
Correct Answer: A
Rationale: Low dissolved oxygen levels are a direct indicator of organic pollution, as the
decomposition of organic matter consumes oxygen. The other options are not specific
indicators of this type of pollution .
Question 9:
A water utility uses chlorination primarily to:
