TCEQ class c water license exam Practice Questions
and 100% Correct Answers – Verified 2026-2027
A public water supply system should maintain residual pressure of
20 psi and a minimum of normal operating pressure of
ANSWERS: 35 psi
Before a new or repaired water line is placed into service, it
must be properly disinfected by providing a chlorine
dosage of _____________________________________________ and
proper detention time
ANSWERS: 50 mg/L
Water bearing formations beneath the earths surface that are used
as a source of water for public water supplies are
ANSWERS: Aquifers
The purpose of an air line on a well is
ANSWERS: Determine Water leves in the well
,The mesh size is an important feature of a well screen because
properly sized openings should
ANSWERS: Reduce the amount of Sand pumped
When treating surface Water, the process of coagularon will be
most affected by the
ANSWERS: pH, alkalinity, temperature, and chemical Dosage
A rapid sand filter should be backwashed When
ANSWERS: The loss of head gauge indicated between 6 and 10 feet
Which of the following is an acceptable disinfection residual at the
far reaches of the distribution System
ANSWERS: 0.2 mg/L free chlorine residual, 0.8 mg/L chloramine
residual when using chloramine treatment, 0.5 mg/L chloramine
for surface water supply, 0.5 mg/L free chlorine residual for
ground water Supply
,What is the approximate total volume of a circular tank in
gallons, if it is 30 feet in diameter, and 15 feet deep
ANSWERS: 79,300 gallons
You are using a chlorinator to provine a dosage of 4.0 mg/L. If
the daily Water usage is 750,000 gallons, the gas chlorinator
feed rate should be set at ____________ pounds per day.
ANSWERS: 25
One gallon of water weighs
ANSWERS: 8.34 lbs.
, One foot of water inside a storage vessel will raise a pressure
gauge at the bottom of the vessel by
ANSWERS: 0.433 lbs. (1 ft. Water creates 0.433 psi of pressure)
A raw water intake structure may not be constructed with _ feet
of a boat ramp, dock, or marina
ANSWERS: 1,000 feet
Common types of pumps for use in water wells are
ANSWERS: Vertical turbine and submersible
_________ is the natural exchange of water between the earth and air
ANSWERS: The hydraulic cycle
If and when a health hazard contamination event occurs in a
public water System, the operator must contact the state
regulatory authority within __________ hours by telephone
ANSWERS: 24 hours
and 100% Correct Answers – Verified 2026-2027
A public water supply system should maintain residual pressure of
20 psi and a minimum of normal operating pressure of
ANSWERS: 35 psi
Before a new or repaired water line is placed into service, it
must be properly disinfected by providing a chlorine
dosage of _____________________________________________ and
proper detention time
ANSWERS: 50 mg/L
Water bearing formations beneath the earths surface that are used
as a source of water for public water supplies are
ANSWERS: Aquifers
The purpose of an air line on a well is
ANSWERS: Determine Water leves in the well
,The mesh size is an important feature of a well screen because
properly sized openings should
ANSWERS: Reduce the amount of Sand pumped
When treating surface Water, the process of coagularon will be
most affected by the
ANSWERS: pH, alkalinity, temperature, and chemical Dosage
A rapid sand filter should be backwashed When
ANSWERS: The loss of head gauge indicated between 6 and 10 feet
Which of the following is an acceptable disinfection residual at the
far reaches of the distribution System
ANSWERS: 0.2 mg/L free chlorine residual, 0.8 mg/L chloramine
residual when using chloramine treatment, 0.5 mg/L chloramine
for surface water supply, 0.5 mg/L free chlorine residual for
ground water Supply
,What is the approximate total volume of a circular tank in
gallons, if it is 30 feet in diameter, and 15 feet deep
ANSWERS: 79,300 gallons
You are using a chlorinator to provine a dosage of 4.0 mg/L. If
the daily Water usage is 750,000 gallons, the gas chlorinator
feed rate should be set at ____________ pounds per day.
ANSWERS: 25
One gallon of water weighs
ANSWERS: 8.34 lbs.
, One foot of water inside a storage vessel will raise a pressure
gauge at the bottom of the vessel by
ANSWERS: 0.433 lbs. (1 ft. Water creates 0.433 psi of pressure)
A raw water intake structure may not be constructed with _ feet
of a boat ramp, dock, or marina
ANSWERS: 1,000 feet
Common types of pumps for use in water wells are
ANSWERS: Vertical turbine and submersible
_________ is the natural exchange of water between the earth and air
ANSWERS: The hydraulic cycle
If and when a health hazard contamination event occurs in a
public water System, the operator must contact the state
regulatory authority within __________ hours by telephone
ANSWERS: 24 hours
