CLASS A WATER OPERATOR FINAL PAPER 2025/2026
QUESTIONS WITH SOLUTIONS RATED A+
✔✔When pressure testing the water main, the test pressure should be ___times as
great as the ________ operating pressure. - ✔✔1.5, normal
✔✔Distribution systems are usually laid out in ____ and/or circular designs. - ✔✔loops
✔✔Dead ends in a system are usually located on ____ shaped or ____ designs. -
✔✔tree, grid
✔✔An operator may refer to Piezometric elevation, static head, or pressure head as
____ height - ✔✔vertical water column
✔✔The main purpose of the water storage facility is to provide ____ amount of water to
average or equalize the ______ demands plus provide ______ pressures to fight fires. -
✔✔sufficient, daily, minimum
✔✔Electrical demand in a wiring system is determined by the amount of ____
consumed. - ✔✔watts
✔✔Baffling inside a storage facility may be needed to prevent "hot spots" and ____
flows. - ✔✔straight through
✔✔A mass of concrete placed at bends and valve structures to prevent pipeline
movement is commonly called a _____. - ✔✔thrust block
✔✔What is the main difference between surface water and groundwater contamination?
- ✔✔groundwater takes longer to recover after contamination
✔✔A cross-connection is a connection between an _____ and an _______ water
supply. - ✔✔approved, unapproved
✔✔According to the CDC, which mechanism or problem has caused more waterborne
disease outbreaks in the US than any other reported factor? - ✔✔leaking backflows
✔✔What type of water meter is used when the water flow widely fluctuates? -
✔✔compound
✔✔How can mechanical damage to water meters be avoided? - ✔✔place it behind the
curb and in a meter box
, ✔✔A piston meter is a _____ meter. - ✔✔displacement
✔✔Name one advantage to using centrifugal pumps. - ✔✔they are easy to repair
✔✔When residential water meters become worn, they have the tendency to ____ all
flows. - ✔✔under register
✔✔_____% of the earth's surface is ocean. - ✔✔75
✔✔Out of all the water on earth, less than _____% of freshwater is immediately
available to humans. - ✔✔1
✔✔The term associated with water that evaporates from living plants is referred to as
_____. - ✔✔evapotranspiration
✔✔_____% of all the water on earth is saltwater. - ✔✔97
✔✔Bacti sample bottles are prepared with a chemical called _____ before they are
sterilized. - ✔✔sodium thiosulfate
✔✔Killing disease causing organisms in the water is the primary purpose of ____ in
water mains. - ✔✔disinfection
✔✔Liquified chlorine gas will expand ____ times its original volume. - ✔✔460
✔✔Chlorine gas is ____ times heavier than breathing air. - ✔✔2.5
✔✔Chlorine gas is considered to be ____% pure. - ✔✔100
✔✔Bleach is approximately _____% pure. - ✔✔5.25
✔✔HTH dry powder chlorine is set at ____% purity. - ✔✔65
✔✔A commonly used method to test for chlorine residual in water is called the ____
method. - ✔✔dpd
✔✔When chlorine gas is added to water, the pH goes down due to the two _____ that
form. - ✔✔acids
✔✔Water with a pH of 7.9 is considered to be ______ or _____. - ✔✔basic, alkaline
QUESTIONS WITH SOLUTIONS RATED A+
✔✔When pressure testing the water main, the test pressure should be ___times as
great as the ________ operating pressure. - ✔✔1.5, normal
✔✔Distribution systems are usually laid out in ____ and/or circular designs. - ✔✔loops
✔✔Dead ends in a system are usually located on ____ shaped or ____ designs. -
✔✔tree, grid
✔✔An operator may refer to Piezometric elevation, static head, or pressure head as
____ height - ✔✔vertical water column
✔✔The main purpose of the water storage facility is to provide ____ amount of water to
average or equalize the ______ demands plus provide ______ pressures to fight fires. -
✔✔sufficient, daily, minimum
✔✔Electrical demand in a wiring system is determined by the amount of ____
consumed. - ✔✔watts
✔✔Baffling inside a storage facility may be needed to prevent "hot spots" and ____
flows. - ✔✔straight through
✔✔A mass of concrete placed at bends and valve structures to prevent pipeline
movement is commonly called a _____. - ✔✔thrust block
✔✔What is the main difference between surface water and groundwater contamination?
- ✔✔groundwater takes longer to recover after contamination
✔✔A cross-connection is a connection between an _____ and an _______ water
supply. - ✔✔approved, unapproved
✔✔According to the CDC, which mechanism or problem has caused more waterborne
disease outbreaks in the US than any other reported factor? - ✔✔leaking backflows
✔✔What type of water meter is used when the water flow widely fluctuates? -
✔✔compound
✔✔How can mechanical damage to water meters be avoided? - ✔✔place it behind the
curb and in a meter box
, ✔✔A piston meter is a _____ meter. - ✔✔displacement
✔✔Name one advantage to using centrifugal pumps. - ✔✔they are easy to repair
✔✔When residential water meters become worn, they have the tendency to ____ all
flows. - ✔✔under register
✔✔_____% of the earth's surface is ocean. - ✔✔75
✔✔Out of all the water on earth, less than _____% of freshwater is immediately
available to humans. - ✔✔1
✔✔The term associated with water that evaporates from living plants is referred to as
_____. - ✔✔evapotranspiration
✔✔_____% of all the water on earth is saltwater. - ✔✔97
✔✔Bacti sample bottles are prepared with a chemical called _____ before they are
sterilized. - ✔✔sodium thiosulfate
✔✔Killing disease causing organisms in the water is the primary purpose of ____ in
water mains. - ✔✔disinfection
✔✔Liquified chlorine gas will expand ____ times its original volume. - ✔✔460
✔✔Chlorine gas is ____ times heavier than breathing air. - ✔✔2.5
✔✔Chlorine gas is considered to be ____% pure. - ✔✔100
✔✔Bleach is approximately _____% pure. - ✔✔5.25
✔✔HTH dry powder chlorine is set at ____% purity. - ✔✔65
✔✔A commonly used method to test for chlorine residual in water is called the ____
method. - ✔✔dpd
✔✔When chlorine gas is added to water, the pH goes down due to the two _____ that
form. - ✔✔acids
✔✔Water with a pH of 7.9 is considered to be ______ or _____. - ✔✔basic, alkaline
