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WATER DISTRIBUTION 2 EXAM 2025/
QUESTIONS AND ANSWERS GRADED A+
(BRAND NEW)
With ground-level reservoirs, why are properly functioning air vents essential?
- To allow surface runoff to flow into the reservoir when it is available
- To avoid weakening the structural stability of the reservoir
- To meet maximum daily flow demands
- To prevent a pressure developing in the reservoir when it fills or a vacuum when it empties or is drained
4
A hydropneumatic or pressure tank contains what type of system?
- A system in which a water pump is controlled by the air pressure in a tank partially filled with water
- A system in which water is compressed in the tank
- A system that provides sufficient storage to meet demands during power outages
- A system that provides unlimited time to do maintenance or repair work on wells, pumps, or water treatment equipment
1
Why must care be used when operating and maintaining hydropneumatic tank facilities, especially the pressure relief valves?
- Because a vacuum can easily develop in the system
- Because O&M is a complex process
because of the high pressure in the tank
- Because of the potential to fall into the water and drowned
3
The capacity of a clear well should be sufficient to allow a water filtration plant to operate a what rate?
- At a constant rate during periods of fire demands
- At a constant rate during periods of peak demands
- At a constant rate during periods of power outages
- At a maximum hourly rate for a 24-hour period
2
How can automatic water level regulation be achieved in storage tanks and reservoirs? By using
- Altitude-control valves
- Automatic gate valves
- Operators calculating anticipated demands
- Variable speed pumps
- Of the most favorable weather conditions
- When agency maintenance crews are available
- When the contractors' crews are available
1
T/F:
Standpipes have a height greater than their diameter
True
T/F:
The main purpose of a surge tank is to store a limited amount of water for use in short-term emergencies
False
Surge tanks main purpose is to control water hammer or regulate the flow of water
T/F:
Water hammer is an annoying but harmless noise that is caused by sudden changes in water pressure
False
Water hammer is caused by a sudden change in water pressure but it is serious and can cause major damage.
T/F:
A foot valve is a type of check valve installed on the pump suction pipe to keep the pump and suction line full of water
True
T/F:
One advantage of using pressure switches to start or stop pumps is that they are relatively easy to install and repair
True
T/F:
Valves in regulator station should be inspected and overhauled at least once a year
True
T/F:
The best time to clean and paint water storage facilities in very cold climates is during the winter when demand is low
False
Cold climates are not taken out of service in the winter.
e. Turbidity
f. All the above
Tastes and odors in treated water storage facilities can be caused by:
a. Activated carbon
b. Algae growths
c. High chlorine residuals
d. Potassium permanganate
e. Silt or clay in suspension
f. All the above
Devices used to measure water depths in storage facilities and control pumps include:
a. Electrodes
b. Floats
c. Magnetic sensors
d. Pressure switches
e. Ultrasonic signals
What problem(s) could be caused by blocked air and overflow vents on a covered ground-level reservoir?
a. Excessive pressure when the reservoir fills
b. Inaccurate water level measurements
c. Tastes and odors associated with stale water
d. Vacuum conditions when the reservoir empties
e. Water hammer when pumps are operating
Safety precautions that must be taken when spraying a disinfectant on the inside of a tank include:
a. Filtering the sprayer pump engine exhaust
b. Having a backup person at the tank entrance
c. Providing adequate ventilation
d. Testing the atmosphere
e. Wearing a safety harness
f. All the above
The time interval between paintings of the outside fo a steel water tank depends on:
a. Durability of paint
b. Proper surface preparation
c. Quality of water
Possible causes of excessive pump vibration or noise include:
a. Foot vale partially clogged
b. Inlet of suction pump insufficiently submerged
c. Misalignment
d. Operation at very low capacity
e. Suction lift too high
f. All the above
Possible causes of a centrifugal pump not delivering water include:
a. Air pocket in suction line
b. Discharge valve open
c. Foot valve malfunctioning
d. Pump not primed
e. Suction lift too high
f. All the above
The rate of corrosion in a metal water storage facility may be increased if the water contains:
a. Carbon dioxide
b. Dissolved carbon
c. Lime
d. Silicates
e. Sulfate-reducing bacteria
f. All the above
Methods of controlling corrosion in water storage tanks include:
a. Application of metallic coatings
b. Cathodic protection
c. Chemical treatment of water
d. Painting inside surfaces
e. Regularly draining and refilling tank
f. All the above
The main purpose of a water storage facility is to provide enough water to:
a. Equalize or average out daily water demands
b. Handle emergency water demands
c. Meet future growth and development demands
d. Pressurize the distribution system
Calculate the volume of water in cubic feet in a rectangular water storage tank 25 feet long, 20 feet wide and the water is 6 feet deep:
a. 360 cu ft
b. 500 cu ft
c. 3,000 cu ft
d. 3,740 cu ft
A water storage tank contains 2,500 cubic feet of water. How many gallons of water are in the tank?
a. 300 gallons
b. 334 gallons
c. 18,700 gallons
d, 20,850 gallons
How many gallons of water are in a circular water storage tank 22 feet in diameter when the water is 6 feet deep?
a. 17,052 gallons
b. 19,012 gallons
c. 21,722 gallons
d. 27,671 gallons
How many pounds of water are in a tank that contains 450 gallons of water?
a. 54 lbs
b. 60 lbs
c. 3,366 lbs
d. 3,753 lbs
Plastic
Most resistant to corrosion
Chlorine gas
heavier than air, extremely toxic, very corrosive to damp atmospheres
Water storage facilities are used to store water from wells or water treatment facilities at times when demands for water are high and to distribute the water during periods of low demand.
- True
- False
- False
- False
- True
Hydropneumatic tanks must contain the proper amount of air to be effective.
- True
- False
- True
In order to maintain specified minimum target water pressures throughout the distribution system, the pump or pumps are operated whenever needed to maintain the desired pressures.
- True
- False
- True
When pumps are operating at for capacity and are put online or taken offline, these pumping conditions can create electrical powerbsurges, which may cause pump motors to trip out (stop working) and produce serious problems.
- True
- False
- True
The pattern of water demands for any particular water distribution system varies during the day and also varies during different days of the week, especially on weekends and holidays.
- True
- False
- True
Be sure the gate to the water storage facility is locked to keep out vandals and unauthorized persons.
- True
- False
- True
Corrosion may occur on the inside or outside of the metal surface of the water storage facility.
- True
- False
- True
- To allow neighborhoods in the community to have their own storage facility
- To maintain a constant pressure at all times on every consumer's tap
- To provide a sufficient amount of water to average or equalize The daily demands on the water supply system
- To store water after treatment until it is properly aged
3
What is a limitation of elevated tanks?
- Continuous pumping is required
- The auxiliary power requirements are increased
- The availability of water for fires is eliminated
- The pressure in the distribution system may vary with the water level in the tank
4
What is disinfection?
- The address meant of pH to kill microorganisms
- The covering of a surface to prevent corrosion
- The inactivation or distraction of disease-producing organisms
- The sterilization of water
Why is sodium thiosulfate added to a bacteriological sampling bottle before it is sterilized?
- To kill or inactive a disease-producing organisms
- To neutralize all chlorine in the water
- To produce an optimum pH
- To provide sufficient nutrients for the bacteria
2
During subzero temperature conditions, how can ice formation in the water storage tanks be minimized?
- By adding nonfreezing chemicals
- By continuously fluctuating water surface level
- By heating the water
- By water conservation practices
2
What are the purposes of a water storage facility?
- To meet the needs for fire protection
