Ohio EPA Water Distribution Class 2 Exam
Question 1. Which distribution system layout provides the greatest redundancy and reliability in
maintaining water supply during pipe breaks?
A) Tree
B) Grid
C) Branch
D) Dead-end
Answer: B
Explanation: Grid systems form loops, allowing multiple flow paths so water can be rerouted during pipe
breaks or maintenance.
Question 2. What is the primary purpose of a water distribution system map?
A) To show population density
B) To locate system components for operations and maintenance
C) To measure water pressure
D) To monitor water quality
Answer: B
Explanation: Distribution system maps help operators locate pipes, valves, hydrants, and other
components for effective management.
Question 3. The most common material used for new water mains in urban areas is:
A) Lead
B) Cast Iron
C) Ductile Iron
D) Galvanized Steel
Answer: C
Explanation: Ductile iron is strong, durable, and flexible, making it the preferred choice for new
installations.
Question 4. Which of the following statements is TRUE about centrifugal pumps?
A) They are self-priming by default
, Ohio EPA Water Distribution Class 2 Exam
B) Their flow increases with increased discharge head
C) They convert mechanical energy into hydraulic energy
D) They are ideal for high-pressure, low-flow applications
Answer: C
Explanation: Centrifugal pumps convert mechanical energy from a motor to hydraulic energy to move
water.
Question 5. In a water distribution system, head loss is primarily caused by:
A) Pump failure
B) Water temperature
C) Friction in pipes and fittings
D) Atmospheric pressure
Answer: C
Explanation: Head loss occurs due to friction as water flows through pipes, valves, and fittings.
Question 6. Which type of storage tank is typically used to provide both storage capacity and system
pressure?
A) Clearwell
B) Ground-level storage
C) Elevated tank
D) Standpipe
Answer: C
Explanation: Elevated tanks use their height to create pressure and store water for demand and
emergencies.
Question 7. The main advantage of a standpipe over a ground-level storage tank is:
A) Lower construction cost
B) Smaller footprint
C) Ability to provide both storage and pressure
D) Easier maintenance
, Ohio EPA Water Distribution Class 2 Exam
Answer: C
Explanation: Standpipes can provide some pressure due to their height, similar to elevated tanks.
Question 8. Before entering service, a newly installed water main must be:
A) Painted
B) Flushed and disinfected
C) Pressurized to system level
D) Buried at least 6 feet deep
Answer: B
Explanation: Flushing and disinfection are required to ensure water quality and public health.
Question 9. Which type of valve is best for throttling flow in a water distribution system?
A) Gate valve
B) Globe valve
C) Butterfly valve
D) Check valve
Answer: C
Explanation: Butterfly valves are commonly used for flow regulation due to their design and ease of use.
Question 10. What is the main function of a check valve in a water distribution system?
A) Shut off water to a section
B) Prevent reverse flow
C) Regulate pressure
D) Control air in mains
Answer: B
Explanation: Check valves only allow flow in one direction, preventing backflow.
Question 11. Fire hydrants should be flushed periodically in order to:
A) Increase water temperature
, Ohio EPA Water Distribution Class 2 Exam
B) Remove sediment and ensure operability
C) Lower system pressure
D) Decrease chlorine residual
Answer: B
Explanation: Flushing hydrants removes sediment and verifies their functionality in emergencies.
Question 12. A compound water meter is typically used for:
A) Residential services
B) Irrigation systems
C) Large commercial or industrial customers
D) Measuring chlorine
Answer: C
Explanation: Compound meters accurately measure both low and high flows, ideal for large users.
Question 13. Which of the following is NOT a function of master meters in a distribution system?
A) System-wide flow measurement
B) Detecting water loss
C) Billing individual households
D) Monitoring system demand
Answer: C
Explanation: Master meters measure total flow into zones, not individual household usage.
Question 14. Which disinfectant is most commonly used in U.S. water distribution systems?
A) Ozone
B) Ultraviolet light
C) Chlorine
D) Potassium permanganate
Answer: C
Explanation: Chlorine is widely used for its effectiveness and residual maintenance capability.
Question 1. Which distribution system layout provides the greatest redundancy and reliability in
maintaining water supply during pipe breaks?
A) Tree
B) Grid
C) Branch
D) Dead-end
Answer: B
Explanation: Grid systems form loops, allowing multiple flow paths so water can be rerouted during pipe
breaks or maintenance.
Question 2. What is the primary purpose of a water distribution system map?
A) To show population density
B) To locate system components for operations and maintenance
C) To measure water pressure
D) To monitor water quality
Answer: B
Explanation: Distribution system maps help operators locate pipes, valves, hydrants, and other
components for effective management.
Question 3. The most common material used for new water mains in urban areas is:
A) Lead
B) Cast Iron
C) Ductile Iron
D) Galvanized Steel
Answer: C
Explanation: Ductile iron is strong, durable, and flexible, making it the preferred choice for new
installations.
Question 4. Which of the following statements is TRUE about centrifugal pumps?
A) They are self-priming by default
, Ohio EPA Water Distribution Class 2 Exam
B) Their flow increases with increased discharge head
C) They convert mechanical energy into hydraulic energy
D) They are ideal for high-pressure, low-flow applications
Answer: C
Explanation: Centrifugal pumps convert mechanical energy from a motor to hydraulic energy to move
water.
Question 5. In a water distribution system, head loss is primarily caused by:
A) Pump failure
B) Water temperature
C) Friction in pipes and fittings
D) Atmospheric pressure
Answer: C
Explanation: Head loss occurs due to friction as water flows through pipes, valves, and fittings.
Question 6. Which type of storage tank is typically used to provide both storage capacity and system
pressure?
A) Clearwell
B) Ground-level storage
C) Elevated tank
D) Standpipe
Answer: C
Explanation: Elevated tanks use their height to create pressure and store water for demand and
emergencies.
Question 7. The main advantage of a standpipe over a ground-level storage tank is:
A) Lower construction cost
B) Smaller footprint
C) Ability to provide both storage and pressure
D) Easier maintenance
, Ohio EPA Water Distribution Class 2 Exam
Answer: C
Explanation: Standpipes can provide some pressure due to their height, similar to elevated tanks.
Question 8. Before entering service, a newly installed water main must be:
A) Painted
B) Flushed and disinfected
C) Pressurized to system level
D) Buried at least 6 feet deep
Answer: B
Explanation: Flushing and disinfection are required to ensure water quality and public health.
Question 9. Which type of valve is best for throttling flow in a water distribution system?
A) Gate valve
B) Globe valve
C) Butterfly valve
D) Check valve
Answer: C
Explanation: Butterfly valves are commonly used for flow regulation due to their design and ease of use.
Question 10. What is the main function of a check valve in a water distribution system?
A) Shut off water to a section
B) Prevent reverse flow
C) Regulate pressure
D) Control air in mains
Answer: B
Explanation: Check valves only allow flow in one direction, preventing backflow.
Question 11. Fire hydrants should be flushed periodically in order to:
A) Increase water temperature
, Ohio EPA Water Distribution Class 2 Exam
B) Remove sediment and ensure operability
C) Lower system pressure
D) Decrease chlorine residual
Answer: B
Explanation: Flushing hydrants removes sediment and verifies their functionality in emergencies.
Question 12. A compound water meter is typically used for:
A) Residential services
B) Irrigation systems
C) Large commercial or industrial customers
D) Measuring chlorine
Answer: C
Explanation: Compound meters accurately measure both low and high flows, ideal for large users.
Question 13. Which of the following is NOT a function of master meters in a distribution system?
A) System-wide flow measurement
B) Detecting water loss
C) Billing individual households
D) Monitoring system demand
Answer: C
Explanation: Master meters measure total flow into zones, not individual household usage.
Question 14. Which disinfectant is most commonly used in U.S. water distribution systems?
A) Ozone
B) Ultraviolet light
C) Chlorine
D) Potassium permanganate
Answer: C
Explanation: Chlorine is widely used for its effectiveness and residual maintenance capability.
