Water Distribution Exam Questions and
Answers | Latest Updated 2025/2026
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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 .- .ANS✓✓-d) .The .Sanitary .Seal
Pure .water .will .exhibit .a .pH .value .of?
a. .0.0
b. .7.0
c. .10.5
d. .14.0 .- .ANS✓✓-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 .- .ANS✓✓-d) .Slightly .Acidic
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 .- .ANS✓✓-b).
.Any .water .that .according .to .recognized .standard .is .safe .for .human .consumption.
,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 .- .ANS✓✓-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 .- .ANS✓✓-a) .Maximum .contaminant .level
The .MBAS .method .is .used .to .determine .levels .of .which .of .the .following .drinking .water
.constituents? .- .ANS✓✓-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 .- .ANS✓✓-b) .Parts .per .million
A .mechanical .device .often .employed .to .prevent .the .over-filling .and/ .on .overdraining .of
.distribution .system .reservoir .is .the? .- .ANS✓✓-Altitude .Valve
The .primary .cause .of .water .quality .deterioration .in .distribution .system .is? .- .ANS✓✓-
Water .age
The .term ."Springline" .applies .to? .- .ANS✓✓-The .midline .of .a .pipeline
When .possible, .a .water .main .should .be .tapped .while .still .pressurized .to? .- .ANS
✓✓-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 .- .ANS✓✓-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 .- .ANS✓✓-b) .Corporation .Stop
The .term ."clearwell" .refers .to .a? .- .ANS✓✓-Reservoir .at .the .outlet .of .a .water
.treatment .plant.
Which .of .the .following .gases .will .deaden .the .sense .of .smell?
a. .Carbon .dioxide
b. .Hydrogen .sulfide
c. .Methane
d. .Oxygen .- .ANS✓✓-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 .- .ANS✓✓-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 .- .ANS✓✓-d) .Water .meters
A .pump .is .experiencing .back-spin .after .it .is .shut .down. .What .is .the .most .likely
.cause? .- .ANS✓✓-Malfunction .check .valve
The .main .purpose .of .a .butterfly .valve .in .a .water .distribution .system .is .for? .-
.ANS✓✓-Isolation
, The .most .likely .means .of .connecting .two .pressure .zone .is .through .a? .- .ANS✓
✓-Pressure .reducing .valve
Which .of .the .following .devices .is .routinely .used .to .reduce .system .pressure? .-
.ANS✓✓-Globe .valve
A .venture .or .a .weir .is .a .device .that .is .used .to .? .- .ANS✓✓-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 .- .ANS✓✓-a) .Gate .valve
Venturi .meters .operate .under .the .principle .of? .- .ANS✓✓-Pressure .differential An
.auxiliary .valve .is .always .located .adjacent .to .a? .- .ANS✓✓-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 .- .ANS✓✓-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 .- .ANS✓✓-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?
When .fully .open, .which .of .the .following .valve .types .will .have .the .highest .friction .loss?
a. .Gate .valve
b. .Globe .valve
c. .Ball .valve