Exam Questions And Correct Answers (Verified
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1. What is the primary purpose of a water distribution system?
A. Provide sewage disposal
B. Supply safe and reliable drinking water
C. Monitor groundwater levels
D. Store stormwater
Answer: B
The system’s main goal is to deliver potable water safely and
consistently.
2. Which component maintains system pressure?
A. Hydrants
B. Backflow preventers
C. Pumps
D. Service saddles
Answer: C
Pumps move water and keep pressure at required levels.
3. The standard minimum pressure in a distribution system under
normal conditions is:
A. 10 psi
B. 20 psi
C. 35 psi
, D. 50 psi
Answer: B
20 psi is widely adopted as the minimum for safe operation.
4. What is the most common type of pipe used today for water
mains?
A. Lead
B. PVC
C. Clay
D. Asphalt-lined
Answer: B
PVC is lightweight, affordable, and corrosion-resistant.
5. The purpose of a blow-off valve is to:
A. Add chemicals
B. Flush out sediment
C. Measure flow
D. Relieve air
Answer: B
Blow-offs allow flushing low-flow areas to remove deposits.
6. Water hammer is caused by:
A. Cold temperatures
B. Sudden valve closure
C. Algae growth
D. High chlorine
Answer: B
Quick valve closure creates a pressure surge known as water
hammer.
, 7. Disinfectant residual in a distribution system is maintained to:
A. Reduce turbidity
B. Prevent pipe corrosion
C. Ensure microbial safety
D. Remove hardness
Answer: C
Residual chlorine protects water from microbial contamination.
8. A cross-connection is a link between:
A. Two meters
B. Potable and non-potable systems
C. Pump stations and reservoirs
D. Storage tanks
Answer: B
Cross-connections create contamination risks.
9. Gate valves are primarily used to:
A. Regulate flow
B. Throttle flow
C. Provide isolation
D. Increase pressure
Answer: C
Gate valves isolate sections of pipe; not ideal for throttling.
10. A corporation stop is installed on a:
A. Hydrant
B. Main
C. Service line
D. Well casing