Water Distribution System Operation
and Maintenance Exam Questions With
Complete Solutions
What are the benefits of a distribution system storage? - CORRECT ANSWER-1.
Demands on the source of water, pumping facilities, and transmission/distribution mains
are more equalized. 2. System flows and pressures are improved/stabilized. 3. Reserve
water supplies are available in case of emergencies.
Types of Common Storage Facilities? - CORRECT ANSWER-Clear wells, elevated
tanks, standpipes, ground-level storage tanks, hydropneumatic/pressure tanks, and
surge tanks
What is Coliform? - CORRECT ANSWER-Group of bacteria found in intestines of warm-
blooded animals, plants, soil, air, and water. It's presence in water is an indication it is
polluted.
What is the proper air:water ratio for a hydropneumatic/pressure tank? - CORRECT
ANSWER-Two-thirds water to one-third air.
atm - CORRECT ANSWER-Abbreviation for "atmosphere". 1 atm = 14.7 psi or 100 kPa
Absorption - CORRECT ANSWER-The taking in or soaking up of one substance into
the body of another by molecular or chemical action
Acid rain - CORRECT ANSWER-Precipitation that has been rendered acidic by airborne
pollutants
,Acidic - CORRECT ANSWER-The condition of water or soil that contains a sufficient
amount of acid substances to lower the pH below 7.0
Acidification - CORRECT ANSWER-The addition of an acid (nitric or sulfuric) to a
sample to lower the pH below 2.0. The purpose of acidification is to fix a sample so it
will not change until it is analyzed.
Acre-Foot - CORRECT ANSWER-A volume of water that covers 1 acre to a depth of 1
foot, or 43,560 cubic feet
Activated Alumina - CORRECT ANSWER-A charged form of aluminum, used with a
synthetic, porous media in an ion exchange adsorption process to remove charged
contaminants
Activated Carbon - CORRECT ANSWER-Adsorptive particles or granules of carbon
usually obtained by heating carbon (ie wood). These particles or granules have a high
capacity to selectively remove certain trace and soluble materials from water.
Adsorbate - CORRECT ANSWER-The material being removed by the adsorption
process.
Adsorbent - CORRECT ANSWER-The material (activated carbon) that is responsible
for removing the undesirable substance in the adsorption process.
Advanced Metering Infrastructure (AMI) - CORRECT ANSWER-Refers to a system that
measures, collects, and analyzes energy usage while interacting with advanced devices
such as water meters through various communication media, either on demand or on
predefined schedules. This infrastructure includes hardware, software, communications,
consumer energy displays and controllers, customer associated systems, meter data
management software, and supplier and network distribution systems.
,Aeration - CORRECT ANSWER-The process of adding air to water, Air can be added to
water by either passing air through water or passing water through air.
Aerobic - CORRECT ANSWER-A condition in which atmospheric or dissolved oxygen is
present in the aquatic environment.
Age Tank - CORRECT ANSWER-A tank used to store a chemical solution of known
concentration for feed to a chemical feeder. It usually stores sufficient chemical solution
to properly treat the water being treated for at least one day. Also known as "Day Tank".
Air Binding - CORRECT ANSWER-The clogging of a filter, pipe, or pump due to the
presence of air released from water. Air entering the filter media is harmful to both the
filtration and backwash processes. Air can prevent the passage of water during the
filtration process and can cause the loss of filter media during the backwash process.
Air Gap - CORRECT ANSWER-An open, vertical drop, or vertical empty space,
between a drinking (potable) water supply and potentially contaminated water. This gap
prevents the contamination of drinking water by backsiphonage because there is no
way potentially contaminated water can reach the drinking water supply.
Alluvial - CORRECT ANSWER-Relating to mud or sand deposited by flowing water.
Alluvial deposits may occur after a heavy rainstorm.
Alternating Current (AC) - CORRECT ANSWER-An electric current that reverses its
direction (positive/negative values) at regular intervals.
Altitude Valve - CORRECT ANSWER-A valve that automatically shuts off the flow into
an elevated tank when the water level in the tank reaches a predetermined level. The
valve automatically opens when the pressure in the distribution system drops below the
pressure in the tank.
, Ambient Temperature - CORRECT ANSWER-Temperature of the surrounding air (or
other medium). For example, temperature of the room where a gas cholorinator is
installed.
Amperage - CORRECT ANSWER-The strength of an electric current measured in
amperes. The amount of electric current flow, similar to the flow of water in gallons per
minute.
Ampere - CORRECT ANSWER-The unit used to measure current strength. The current
produced by an electromotive force of one volt acting through a resistance of one ohm.
Amperometric - CORRECT ANSWER-A method of measurement that records electric
current flowing or generated, rather than recording voltage. Amperometric titration is a
means of measuring concentrations of certain substances in water.
Amplitude - CORRECT ANSWER-The maximum stregth of an alternating current during
its cycle as distinguished from the mean or effective strength.
Anaerobic - CORRECT ANSWER-A condition in which atmospheric or dissolved
oxygen is not present in the aquatic environment.
Analog - CORRECT ANSWER-The continuously variable signal type sent to an analog
instrument (for example, 4-20 mA)
Analog Readout - CORRECT ANSWER-The readout of an instrument by a pointer.
Analyzer - CORRECT ANSWER-A device that conducts a periodic or continuous
measurement of turbidity or some factor such as chlorine or fluoride concentration.
and Maintenance Exam Questions With
Complete Solutions
What are the benefits of a distribution system storage? - CORRECT ANSWER-1.
Demands on the source of water, pumping facilities, and transmission/distribution mains
are more equalized. 2. System flows and pressures are improved/stabilized. 3. Reserve
water supplies are available in case of emergencies.
Types of Common Storage Facilities? - CORRECT ANSWER-Clear wells, elevated
tanks, standpipes, ground-level storage tanks, hydropneumatic/pressure tanks, and
surge tanks
What is Coliform? - CORRECT ANSWER-Group of bacteria found in intestines of warm-
blooded animals, plants, soil, air, and water. It's presence in water is an indication it is
polluted.
What is the proper air:water ratio for a hydropneumatic/pressure tank? - CORRECT
ANSWER-Two-thirds water to one-third air.
atm - CORRECT ANSWER-Abbreviation for "atmosphere". 1 atm = 14.7 psi or 100 kPa
Absorption - CORRECT ANSWER-The taking in or soaking up of one substance into
the body of another by molecular or chemical action
Acid rain - CORRECT ANSWER-Precipitation that has been rendered acidic by airborne
pollutants
,Acidic - CORRECT ANSWER-The condition of water or soil that contains a sufficient
amount of acid substances to lower the pH below 7.0
Acidification - CORRECT ANSWER-The addition of an acid (nitric or sulfuric) to a
sample to lower the pH below 2.0. The purpose of acidification is to fix a sample so it
will not change until it is analyzed.
Acre-Foot - CORRECT ANSWER-A volume of water that covers 1 acre to a depth of 1
foot, or 43,560 cubic feet
Activated Alumina - CORRECT ANSWER-A charged form of aluminum, used with a
synthetic, porous media in an ion exchange adsorption process to remove charged
contaminants
Activated Carbon - CORRECT ANSWER-Adsorptive particles or granules of carbon
usually obtained by heating carbon (ie wood). These particles or granules have a high
capacity to selectively remove certain trace and soluble materials from water.
Adsorbate - CORRECT ANSWER-The material being removed by the adsorption
process.
Adsorbent - CORRECT ANSWER-The material (activated carbon) that is responsible
for removing the undesirable substance in the adsorption process.
Advanced Metering Infrastructure (AMI) - CORRECT ANSWER-Refers to a system that
measures, collects, and analyzes energy usage while interacting with advanced devices
such as water meters through various communication media, either on demand or on
predefined schedules. This infrastructure includes hardware, software, communications,
consumer energy displays and controllers, customer associated systems, meter data
management software, and supplier and network distribution systems.
,Aeration - CORRECT ANSWER-The process of adding air to water, Air can be added to
water by either passing air through water or passing water through air.
Aerobic - CORRECT ANSWER-A condition in which atmospheric or dissolved oxygen is
present in the aquatic environment.
Age Tank - CORRECT ANSWER-A tank used to store a chemical solution of known
concentration for feed to a chemical feeder. It usually stores sufficient chemical solution
to properly treat the water being treated for at least one day. Also known as "Day Tank".
Air Binding - CORRECT ANSWER-The clogging of a filter, pipe, or pump due to the
presence of air released from water. Air entering the filter media is harmful to both the
filtration and backwash processes. Air can prevent the passage of water during the
filtration process and can cause the loss of filter media during the backwash process.
Air Gap - CORRECT ANSWER-An open, vertical drop, or vertical empty space,
between a drinking (potable) water supply and potentially contaminated water. This gap
prevents the contamination of drinking water by backsiphonage because there is no
way potentially contaminated water can reach the drinking water supply.
Alluvial - CORRECT ANSWER-Relating to mud or sand deposited by flowing water.
Alluvial deposits may occur after a heavy rainstorm.
Alternating Current (AC) - CORRECT ANSWER-An electric current that reverses its
direction (positive/negative values) at regular intervals.
Altitude Valve - CORRECT ANSWER-A valve that automatically shuts off the flow into
an elevated tank when the water level in the tank reaches a predetermined level. The
valve automatically opens when the pressure in the distribution system drops below the
pressure in the tank.
, Ambient Temperature - CORRECT ANSWER-Temperature of the surrounding air (or
other medium). For example, temperature of the room where a gas cholorinator is
installed.
Amperage - CORRECT ANSWER-The strength of an electric current measured in
amperes. The amount of electric current flow, similar to the flow of water in gallons per
minute.
Ampere - CORRECT ANSWER-The unit used to measure current strength. The current
produced by an electromotive force of one volt acting through a resistance of one ohm.
Amperometric - CORRECT ANSWER-A method of measurement that records electric
current flowing or generated, rather than recording voltage. Amperometric titration is a
means of measuring concentrations of certain substances in water.
Amplitude - CORRECT ANSWER-The maximum stregth of an alternating current during
its cycle as distinguished from the mean or effective strength.
Anaerobic - CORRECT ANSWER-A condition in which atmospheric or dissolved
oxygen is not present in the aquatic environment.
Analog - CORRECT ANSWER-The continuously variable signal type sent to an analog
instrument (for example, 4-20 mA)
Analog Readout - CORRECT ANSWER-The readout of an instrument by a pointer.
Analyzer - CORRECT ANSWER-A device that conducts a periodic or continuous
measurement of turbidity or some factor such as chlorine or fluoride concentration.
