Water Distribution Exam Questions and
Answers 100% Correct
Potable water may be defined as:
a. Any water that occasionally may be polluted from another source
b. Any water that, according to recognized standards, is safe for consumption
c. Water high in organic content
d. Water that has been transported from outside the service area - ANSWER-b). Any
water that according to recognized standard is safe for human consumption.
To prevent the entry of surface contamination into a well is the purpose of:
a. The well casing
b. The louvers or slots
c. Well development
d. The sanitary seal - ANSWER-d) The Sanitary Seal
Pure water will exhibit a pH value of?
a. 0.0
b. 7.0
c. 10.5
d. 14.0 - ANSWER-b) 7.0
A pH reading of 6.0 units indicates that the water sample is:
a. Very acidic
b. Slightly alkaline
c. Very alkaline
d. Slightly acidic - ANSWER-d) Slightly Acidic
In drinking water quality, "TDS" is the abbreviation for?
a)Total digestable substances
b) Total dissolved solids
c) Time-delayed sicknesses
d) Terminal diseases started - ANSWER-b) Total Dissolved Solids
In drinking water regulations, the abbreviation "MCL" stands for?
a) Maximum contaminant level
b) Multiple constituent levels
c) Most common level
d) Minimum considered legal - ANSWER-a) Maximum contaminant level
,The MBAS method is used to determine levels of which of the following drinking
water constituents? - ANSWER-Forming Agent
In water quality, the symbol "mg/L" is equivalent to:
a. Micrograms per liter
b. Parts per million
c. Parts per billion
d. Mostly good levels - ANSWER-b) Parts per million
The term "clearwell" refers to a? - ANSWER-Reservoir at the outlet of a water
treatment plant.
A mechanical device often employed to prevent the over-filling and/ on over-draining
of distribution system reservoir is the? - ANSWER-Altitude Valve
The primary cause of water quality deterioration in distribution system is? -
ANSWER-Water age
The term "Springline" applies to? - ANSWER-The midline of a pipeline
When possible, a water main should be tapped while still pressurized to? -
ANSWER-Minimize contamination risk
A connection made into a water main that is full of under pressure is called a?
a. Cross connection
b. Valve box
c. Wet tap
d. Spinal tap - ANSWER-c) Wet tap
A special valve that is used almost exclusively to facilitate making connections to
pipeline is the?
a. Gate valve
b. Corporation stop
c. Altitude valve
d. Auxiliary valve - ANSWER-b) Corporation Stop
Which of the following gases will deaden the sense of smell?
a. Carbon dioxide
b. Hydrogen sulfide
c. Methane
d. Oxygen - ANSWER-b) Hydrogen Sulfide
The most commonly used meter on small domestic services?
a. Venturi meter
,b. Propeller meter
c. Orifice plate meter
d. Nutating disc meter - ANSWER-d) Nutating Disk Meter
A Nutating disk is found in certain?
a. Positive displacement pumps
b. Main line valves
c. Chemical feeders
d. Water meters - ANSWER-d) Water meters
A pump is experiencing back-spin after it is shut down. What is the most likely
cause? - ANSWER-Malfunction check valve
When fully open, which of the following valve types will have the highest friction
loss?
a. Gate valve
b. Globe valve
c. Ball valve
d. All will have about the same friction loss. - ANSWER-b) Globe valve
The main purpose of a butterfly valve in a water distribution system is for? -
ANSWER-Isolation
The most likely means of connecting two pressure zone is through a? - ANSWER-
Pressure reducing valve
Which of the following devices is routinely used to reduce system pressure? -
ANSWER-Globe valve
A venture or a weir is a device that is used to ? - ANSWER-Measured water flow
The most common valve in water distribution system is the?
a. Gate valve
b. Butterfly valve
c. Check valve
d. Globe valve - ANSWER-a) Gate valve
Venturi meters operate under the principle of? - ANSWER-Pressure differential
An auxiliary valve is always located adjacent to a? - ANSWER-Fire Hydrants
If you encounter a liquid chlorine leak in a one-ton container. What action should you
take first, to reduce the severity of the leak?
a. Apply a caustic solution
b. Spray the container with water
c. Spray the container with an ammonia solution
, d. Rotate the container to place the leak at the top - ANSWER-d) Rotate the
container to place the leak at the top
The most commonly used water disinfectant in the United States is?
a. Chlorine Dioxide
b. Ozone
c. Chlorine and Ammonia (chloramines)
d. Chlorine - ANSWER-d) Chlorine
When collecting a distribution system sample, the water should be allowed to run for
a period of time prior to sample collection. This period of time is?
a. At least two minutes
b. At least five minutes
c. At least thirty minutes
d. As long as necessary to permit clearing of the service line - ANSWER-d) As long
as necessary to permit clearing of the service line
Sample bottles which are furnished by a certified laboratory for collection of
bacteriological same?
a. Should be rinsed with the water to be sampled before use
b. Should be rinsed with a chlorine solution before use
c. Should be rinsed with distilled water before use
d. Are ready to use - ANSWER-d) Ready to use
A device that automatically shuts off flow into an elevated storage tank when water
level in the tank reaches a preset level is termed a?
a. Air / vacuum relief valve
b. Wet-barrel hydrant
c. Altitude valve
d. Angle valve - ANSWER-c) Altitude valve
red - ANSWER-Electric Power line, Cable Conduit and Lighting
Yellow - ANSWER-Gas, Oil, Stream, Petroleum, or Gasesous Materials
Orange - ANSWER-Communications, Alarm or Signal Lines, or Conduit
Purple - ANSWER-Reclaimed Water, Irrigation, and Slurry Lines
Blue - ANSWER-Potable Water
Green - ANSWER-Sewers and Drain Lines
Pink - ANSWER-Temporary Survey Markings
White - ANSWER-Proposed Excavating
Answers 100% Correct
Potable water may be defined as:
a. Any water that occasionally may be polluted from another source
b. Any water that, according to recognized standards, is safe for consumption
c. Water high in organic content
d. Water that has been transported from outside the service area - ANSWER-b). Any
water that according to recognized standard is safe for human consumption.
To prevent the entry of surface contamination into a well is the purpose of:
a. The well casing
b. The louvers or slots
c. Well development
d. The sanitary seal - ANSWER-d) The Sanitary Seal
Pure water will exhibit a pH value of?
a. 0.0
b. 7.0
c. 10.5
d. 14.0 - ANSWER-b) 7.0
A pH reading of 6.0 units indicates that the water sample is:
a. Very acidic
b. Slightly alkaline
c. Very alkaline
d. Slightly acidic - ANSWER-d) Slightly Acidic
In drinking water quality, "TDS" is the abbreviation for?
a)Total digestable substances
b) Total dissolved solids
c) Time-delayed sicknesses
d) Terminal diseases started - ANSWER-b) Total Dissolved Solids
In drinking water regulations, the abbreviation "MCL" stands for?
a) Maximum contaminant level
b) Multiple constituent levels
c) Most common level
d) Minimum considered legal - ANSWER-a) Maximum contaminant level
,The MBAS method is used to determine levels of which of the following drinking
water constituents? - ANSWER-Forming Agent
In water quality, the symbol "mg/L" is equivalent to:
a. Micrograms per liter
b. Parts per million
c. Parts per billion
d. Mostly good levels - ANSWER-b) Parts per million
The term "clearwell" refers to a? - ANSWER-Reservoir at the outlet of a water
treatment plant.
A mechanical device often employed to prevent the over-filling and/ on over-draining
of distribution system reservoir is the? - ANSWER-Altitude Valve
The primary cause of water quality deterioration in distribution system is? -
ANSWER-Water age
The term "Springline" applies to? - ANSWER-The midline of a pipeline
When possible, a water main should be tapped while still pressurized to? -
ANSWER-Minimize contamination risk
A connection made into a water main that is full of under pressure is called a?
a. Cross connection
b. Valve box
c. Wet tap
d. Spinal tap - ANSWER-c) Wet tap
A special valve that is used almost exclusively to facilitate making connections to
pipeline is the?
a. Gate valve
b. Corporation stop
c. Altitude valve
d. Auxiliary valve - ANSWER-b) Corporation Stop
Which of the following gases will deaden the sense of smell?
a. Carbon dioxide
b. Hydrogen sulfide
c. Methane
d. Oxygen - ANSWER-b) Hydrogen Sulfide
The most commonly used meter on small domestic services?
a. Venturi meter
,b. Propeller meter
c. Orifice plate meter
d. Nutating disc meter - ANSWER-d) Nutating Disk Meter
A Nutating disk is found in certain?
a. Positive displacement pumps
b. Main line valves
c. Chemical feeders
d. Water meters - ANSWER-d) Water meters
A pump is experiencing back-spin after it is shut down. What is the most likely
cause? - ANSWER-Malfunction check valve
When fully open, which of the following valve types will have the highest friction
loss?
a. Gate valve
b. Globe valve
c. Ball valve
d. All will have about the same friction loss. - ANSWER-b) Globe valve
The main purpose of a butterfly valve in a water distribution system is for? -
ANSWER-Isolation
The most likely means of connecting two pressure zone is through a? - ANSWER-
Pressure reducing valve
Which of the following devices is routinely used to reduce system pressure? -
ANSWER-Globe valve
A venture or a weir is a device that is used to ? - ANSWER-Measured water flow
The most common valve in water distribution system is the?
a. Gate valve
b. Butterfly valve
c. Check valve
d. Globe valve - ANSWER-a) Gate valve
Venturi meters operate under the principle of? - ANSWER-Pressure differential
An auxiliary valve is always located adjacent to a? - ANSWER-Fire Hydrants
If you encounter a liquid chlorine leak in a one-ton container. What action should you
take first, to reduce the severity of the leak?
a. Apply a caustic solution
b. Spray the container with water
c. Spray the container with an ammonia solution
, d. Rotate the container to place the leak at the top - ANSWER-d) Rotate the
container to place the leak at the top
The most commonly used water disinfectant in the United States is?
a. Chlorine Dioxide
b. Ozone
c. Chlorine and Ammonia (chloramines)
d. Chlorine - ANSWER-d) Chlorine
When collecting a distribution system sample, the water should be allowed to run for
a period of time prior to sample collection. This period of time is?
a. At least two minutes
b. At least five minutes
c. At least thirty minutes
d. As long as necessary to permit clearing of the service line - ANSWER-d) As long
as necessary to permit clearing of the service line
Sample bottles which are furnished by a certified laboratory for collection of
bacteriological same?
a. Should be rinsed with the water to be sampled before use
b. Should be rinsed with a chlorine solution before use
c. Should be rinsed with distilled water before use
d. Are ready to use - ANSWER-d) Ready to use
A device that automatically shuts off flow into an elevated storage tank when water
level in the tank reaches a preset level is termed a?
a. Air / vacuum relief valve
b. Wet-barrel hydrant
c. Altitude valve
d. Angle valve - ANSWER-c) Altitude valve
red - ANSWER-Electric Power line, Cable Conduit and Lighting
Yellow - ANSWER-Gas, Oil, Stream, Petroleum, or Gasesous Materials
Orange - ANSWER-Communications, Alarm or Signal Lines, or Conduit
Purple - ANSWER-Reclaimed Water, Irrigation, and Slurry Lines
Blue - ANSWER-Potable Water
Green - ANSWER-Sewers and Drain Lines
Pink - ANSWER-Temporary Survey Markings
White - ANSWER-Proposed Excavating
