WATER DISTRIBUTION GRADE III EXAM TEST WITH
LATEST UPDATED (QUESTIONS AND ANSWERS) ALREADY
PASSED!!
Who requires water operator certification in the United States? Correct
Answers The EPA
Which type of hydrant has no main valve but has a separate valve for
each nozzle outlet? Correct Answers Wet Barrel
When is the best time to flush a distribution system? Correct Answers
Late at night
A broken water main can cause a loss of pressure in a distribution
system. What kind of problem can this create? Correct Answers Back
siphonage
If the water temperature increases, what affect does this have on
chlorines ability to disinfect water? Correct Answers It has no effect
What is the cause of turbidity in water? Correct Answers Dissolved
minerals
It has been determined that a customers backflow device has failed, what
steps should the utility take? Correct Answers Notify customer to repair
it immediately or service may be terminated
,What chemical method can a utility use to disinfect a water supply so it
is safe to drink? Correct Answers Sodium hypochlorite, calcium
hypochlorite, ozone
What is a sample called if an operator takes a sample in the distribution
system to test for chlorine or coliform? Correct Answers Grab sample
What type of records should be kept daily in a water distribution
system? Correct Answers Chlorine residuals, flows, and time cards
Which of the following provides a profile of hazardous substances or
mixtures? Correct Answers MSDS
Why should an operator use precautions when working with or around la
hydro pneumatic pressure tank? Correct Answers The high pressure in
these tanks could injure the operator if caution is not used
What is in a surge tank that prevents water hammer? Correct Answers
An air space
If a monthly coliform sample was positive, what should the utility do
first? Correct Answers Retest all sites listed in the site sampling plan
If a corrosion problem exists within a distribution system, what
chemicals can be used to correct this problem? Correct Answers
Orthophosphates, caustic soda, lime & soda ash
, Elevated storage tanks are usually located in towns where the land is:
Correct Answers Flat
Water storage tanks are designed to provide potable water during:
Correct Answers Average and peak demands, emergencies such as fires,
normal activities
A water storage tank is on a hill that is 115 ft in elevation above the first
fire hydrant. The storage tank measures 60 ft long, 50 ft wide and 40 ft
tall. What is the pressure at the hydrant if the tank is full? Correct
Answers 115ft elevation + 40ft tall tank = 155ft x .433 = 67psi
An atmosphere is defined as oxygen deficient if it contains less than
what percent oxygen by volume? Correct Answers 19.5
A centrifugal pump should never be operated unless the impeller is
submerged in water or primed. What could cause a centrifugal pump to
lose its prime? Correct Answers A malfunctioning foot valve
The primary drinking water standards apply to drinking water
contaminants that may have an adverse effect on Correct Answers
Human Health
When working inside a water storage tank, a person should always wear
a safety harness so that they may be rescued if they become injured or
LATEST UPDATED (QUESTIONS AND ANSWERS) ALREADY
PASSED!!
Who requires water operator certification in the United States? Correct
Answers The EPA
Which type of hydrant has no main valve but has a separate valve for
each nozzle outlet? Correct Answers Wet Barrel
When is the best time to flush a distribution system? Correct Answers
Late at night
A broken water main can cause a loss of pressure in a distribution
system. What kind of problem can this create? Correct Answers Back
siphonage
If the water temperature increases, what affect does this have on
chlorines ability to disinfect water? Correct Answers It has no effect
What is the cause of turbidity in water? Correct Answers Dissolved
minerals
It has been determined that a customers backflow device has failed, what
steps should the utility take? Correct Answers Notify customer to repair
it immediately or service may be terminated
,What chemical method can a utility use to disinfect a water supply so it
is safe to drink? Correct Answers Sodium hypochlorite, calcium
hypochlorite, ozone
What is a sample called if an operator takes a sample in the distribution
system to test for chlorine or coliform? Correct Answers Grab sample
What type of records should be kept daily in a water distribution
system? Correct Answers Chlorine residuals, flows, and time cards
Which of the following provides a profile of hazardous substances or
mixtures? Correct Answers MSDS
Why should an operator use precautions when working with or around la
hydro pneumatic pressure tank? Correct Answers The high pressure in
these tanks could injure the operator if caution is not used
What is in a surge tank that prevents water hammer? Correct Answers
An air space
If a monthly coliform sample was positive, what should the utility do
first? Correct Answers Retest all sites listed in the site sampling plan
If a corrosion problem exists within a distribution system, what
chemicals can be used to correct this problem? Correct Answers
Orthophosphates, caustic soda, lime & soda ash
, Elevated storage tanks are usually located in towns where the land is:
Correct Answers Flat
Water storage tanks are designed to provide potable water during:
Correct Answers Average and peak demands, emergencies such as fires,
normal activities
A water storage tank is on a hill that is 115 ft in elevation above the first
fire hydrant. The storage tank measures 60 ft long, 50 ft wide and 40 ft
tall. What is the pressure at the hydrant if the tank is full? Correct
Answers 115ft elevation + 40ft tall tank = 155ft x .433 = 67psi
An atmosphere is defined as oxygen deficient if it contains less than
what percent oxygen by volume? Correct Answers 19.5
A centrifugal pump should never be operated unless the impeller is
submerged in water or primed. What could cause a centrifugal pump to
lose its prime? Correct Answers A malfunctioning foot valve
The primary drinking water standards apply to drinking water
contaminants that may have an adverse effect on Correct Answers
Human Health
When working inside a water storage tank, a person should always wear
a safety harness so that they may be rescued if they become injured or
