1|Page
CSWO Exam 2025 / Certified Storm Water Operator
Exam Prep with 100 Questions and Correct Answers
from the CSWO and SESC Comprehensive Training
Manual
State Agency responsince for enforcing the safe drinking
water act in Texas - ...ANSWER...✓✓ Texas Commission
on environmental Quality
What minerals can cause water hardness -
...ANSWER...✓✓ Calcium and magnesium
A public water system must at all times provide -
...ANSWER...✓✓ Adequate quantity of water, pressure,
and disinfection
A source groundwater would be - ...ANSWER...✓✓ aquifer
Fecal coliform organisms sometimes found in water
supplies are an indication that - ...ANSWER...✓✓ Water
supply is contaminated, harmful bacteria may be present,
possible pathogenic organisms in the water, water is
unsuitable for drinking
,2|Page
A disease that may be spread by inadequately disinfected
water - ...ANSWER...✓✓ Dysentery
A common chemical used in disinfection of small water
supply is - ...ANSWER...✓✓ Calcium hypochlorite
A physical connection between a potable water supply
and house well would be - ...ANSWER...✓✓ A cross
connection
The amount of chlorine in mg/L that is used up by
reacting with iron organics of bacteria is called -
...ANSWER...✓✓ Demand
Which of the following is a physical characteristic of
chlorine gas - ...ANSWER...✓✓ Greenish-Yellow Color,
heavier than air, pungent penetrating odor, corrosive
Which of the following would be considered a part of a
hypo-chlorinator system - ...ANSWER...✓✓ Solution feed
pump
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According to state requirements, all public water Supply
wells should be provided with a raised concrete sealing
block, screened vents, and- - ...ANSWER...✓✓ A flow
measuring device
Drawdown of a water well is determined by -
...ANSWER...✓✓ Difference in static and pumping levels
pH of water indicates - ...ANSWER...✓✓ If it's acidic or
basic
The pH of water is expressed on a pH scale of -
...ANSWER...✓✓ 0-14
Water that is considered neutral is expressed on the pH
scale at - ...ANSWER...✓✓ 7.0
Which of the following is a required Step in collecting a
routine distribution sample for bacteriological testing? -
...ANSWER...✓✓ Use of an approved, sterile sample
container
CSWO Exam 2025 / Certified Storm Water Operator
Exam Prep with 100 Questions and Correct Answers
from the CSWO and SESC Comprehensive Training
Manual
State Agency responsince for enforcing the safe drinking
water act in Texas - ...ANSWER...✓✓ Texas Commission
on environmental Quality
What minerals can cause water hardness -
...ANSWER...✓✓ Calcium and magnesium
A public water system must at all times provide -
...ANSWER...✓✓ Adequate quantity of water, pressure,
and disinfection
A source groundwater would be - ...ANSWER...✓✓ aquifer
Fecal coliform organisms sometimes found in water
supplies are an indication that - ...ANSWER...✓✓ Water
supply is contaminated, harmful bacteria may be present,
possible pathogenic organisms in the water, water is
unsuitable for drinking
,2|Page
A disease that may be spread by inadequately disinfected
water - ...ANSWER...✓✓ Dysentery
A common chemical used in disinfection of small water
supply is - ...ANSWER...✓✓ Calcium hypochlorite
A physical connection between a potable water supply
and house well would be - ...ANSWER...✓✓ A cross
connection
The amount of chlorine in mg/L that is used up by
reacting with iron organics of bacteria is called -
...ANSWER...✓✓ Demand
Which of the following is a physical characteristic of
chlorine gas - ...ANSWER...✓✓ Greenish-Yellow Color,
heavier than air, pungent penetrating odor, corrosive
Which of the following would be considered a part of a
hypo-chlorinator system - ...ANSWER...✓✓ Solution feed
pump
, 3|Page
According to state requirements, all public water Supply
wells should be provided with a raised concrete sealing
block, screened vents, and- - ...ANSWER...✓✓ A flow
measuring device
Drawdown of a water well is determined by -
...ANSWER...✓✓ Difference in static and pumping levels
pH of water indicates - ...ANSWER...✓✓ If it's acidic or
basic
The pH of water is expressed on a pH scale of -
...ANSWER...✓✓ 0-14
Water that is considered neutral is expressed on the pH
scale at - ...ANSWER...✓✓ 7.0
Which of the following is a required Step in collecting a
routine distribution sample for bacteriological testing? -
...ANSWER...✓✓ Use of an approved, sterile sample
container
