Water Distribution Operator Math ULTIMATE EXAM BANK (350
Q&A) – Full 2024/2026 Study Guide: Volume, Flow, Dosage,
Pressure & Horsepower (Grades 1-4)
This 350-question master bank is professionally engineered to cover the ABC (Association of Boards
of Certification) and state-level licensing standards. It bridges the gap between complex hydraulic
theory and the practical math needed to pass your certification on the first attempt.
1. A water tank is 30 feet in diameter and 20 feet high. What is the approximate volume
in gallons?
A) 14,130 gallons
B) 105,692 gallons
C) 70,461 gallons
D) 15,650 gallons
Correct Answer: B
Rationale: Volume formula:
. Calculation:
gallons.
2. How many pounds of 65% calcium hypochlorite are required to treat 2.5 million
gallons of water at a dosage of 1.5 mg/L?
, 2026 UPDATED QUESTIONS DOWNLOAD
A) 31.3 lbs
B) 48.1 lbs
C) 19.3 lbs
D) 20.3 lbs
Correct Answer: B
Rationale: Use the Pounds Formula:
. Calculation:
lbs.
3. What is the pressure in PSI at the bottom of a reservoir that has a water depth of 85
feet?
A) 196 PSI
B) 36.8 PSI
C) 85 PSI
D) 0.433 PSI
Correct Answer: B
Rationale:
. Calculation:
PSI.
4. A pump delivers 650 gallons per minute (GPM). What is this flow rate in Million
Gallons per Day (MGD)?
, 2026 UPDATED QUESTIONS DOWNLOAD
A) 0.650 MGD
B) 1.25 MGD
C) 0.936 MGD
D) 0.451 MGD
Correct Answer: C
Rationale:
. Calculation:
MGD.
5. A 10-inch water main must be flushed at a velocity of 2.5 feet per second (fps). What
is the required flow rate in GPM?
A) 612 GPM
B) 450 GPM
C) 825 GPM
D) 314 GPM
Correct Answer: A
Rationale:
, 2026 UPDATED QUESTIONS DOWNLOAD
. Calculation:
GPM.
6. How many gallons of water are contained in 2,000 feet of 6-inch diameter pipe?
A) 2,938 gallons
B) 1,469 gallons
C) 5,876 gallons
D) 8,240 gallons
Correct Answer: A
Rationale:
. Calculation: