WATER DISTRIBUTION PRACTICE TEST D1 /D2 QUESTIONS WITH
CORRECT ANSWERS 2025/2026
The only absolutely reliable method of backflow prevention is the use of - CORRECT ANSWER -
Air Gap
The bubbles formed in a positive multiple tube fermentation test are - CORRECT ANSWER -
Carbon Dioxide
The maximum rate of withdrawal of gas from a 150lb chlorine cylinder in 24-hours is - CORRECT
ANSWER -40 lbs
If you encounter a liquid chlorine leak in a one tone container, what action should you take first,
to reduce the severity of the leak? - CORRECT ANSWER -Rotate the container to place the leak
at the top
The most commonly used water disinfectant in the United States is - CORRECT ANSWER -
Chlorine
When collecting a distribution system sample, the water should be allowed to run for a period
of time prior to sample collection. How long - CORRECT ANSWER -As long as necessary to
permit cleaning of service line
Sample bottles wich are furnished by a certified laboratory for collection of bacteriological
samples - CORRECT ANSWER -Are ready to use
The difference between water pressure upstream and downstream of a pump when it is not in
operations is know as the - CORRECT ANSWER -Total static head
, A device that automatically shuts off flow in an elevated storage tank when the water level in
the tank reache a preset level is termed a - CORRECT ANSWER -Altitude valve
In an occupied trench requiring personal egress what is the maximum allowable distance
between a worker and an exit letter - CORRECT ANSWER -25 feet
A water bearing formation in the soil is referred to as - CORRECT ANSWER -An aquifer
The distance between the static water level and the pumping water level is termed the -
CORRECT ANSWER -Drawdown
To prevent the entry of surface contamination into a well is the purpose of - CORRECT ANSWER -
Sanitary seal
The presence of coliform bacteria in a distribution system - CORRECT ANSWER -Indicates that
pathogenic organisms may be present also
The most common valve type in water distribution system is the - CORRECT ANSWER -Gate
valve
A Venturi is a device used to - CORRECT ANSWER -Measure water flow
Backspin is occurring after well shut down this indicates - CORRECT ANSWER -A faulty check
valve
A ph reading of 6.0 units indicates the water sample is - CORRECT ANSWER -Slightly acidic
Chlorine gas - CORRECT ANSWER -Is heavier than air
CORRECT ANSWERS 2025/2026
The only absolutely reliable method of backflow prevention is the use of - CORRECT ANSWER -
Air Gap
The bubbles formed in a positive multiple tube fermentation test are - CORRECT ANSWER -
Carbon Dioxide
The maximum rate of withdrawal of gas from a 150lb chlorine cylinder in 24-hours is - CORRECT
ANSWER -40 lbs
If you encounter a liquid chlorine leak in a one tone container, what action should you take first,
to reduce the severity of the leak? - CORRECT ANSWER -Rotate the container to place the leak
at the top
The most commonly used water disinfectant in the United States is - CORRECT ANSWER -
Chlorine
When collecting a distribution system sample, the water should be allowed to run for a period
of time prior to sample collection. How long - CORRECT ANSWER -As long as necessary to
permit cleaning of service line
Sample bottles wich are furnished by a certified laboratory for collection of bacteriological
samples - CORRECT ANSWER -Are ready to use
The difference between water pressure upstream and downstream of a pump when it is not in
operations is know as the - CORRECT ANSWER -Total static head
, A device that automatically shuts off flow in an elevated storage tank when the water level in
the tank reache a preset level is termed a - CORRECT ANSWER -Altitude valve
In an occupied trench requiring personal egress what is the maximum allowable distance
between a worker and an exit letter - CORRECT ANSWER -25 feet
A water bearing formation in the soil is referred to as - CORRECT ANSWER -An aquifer
The distance between the static water level and the pumping water level is termed the -
CORRECT ANSWER -Drawdown
To prevent the entry of surface contamination into a well is the purpose of - CORRECT ANSWER -
Sanitary seal
The presence of coliform bacteria in a distribution system - CORRECT ANSWER -Indicates that
pathogenic organisms may be present also
The most common valve type in water distribution system is the - CORRECT ANSWER -Gate
valve
A Venturi is a device used to - CORRECT ANSWER -Measure water flow
Backspin is occurring after well shut down this indicates - CORRECT ANSWER -A faulty check
valve
A ph reading of 6.0 units indicates the water sample is - CORRECT ANSWER -Slightly acidic
Chlorine gas - CORRECT ANSWER -Is heavier than air
