WATER TREATMENT EXAM REVIEW
QUESTIONS WITH ACCURATE SOLUTIONS
2026
▶ Water Intake structures Answer: Provide water to the treatment plant,
prevent large debris from entering the treatment process, and constructed
to provide pressure to the distribution system.
▶ What is pure water? Answer: Pure water is the absence of soluble and
insoluble substances in it.
▶ Can pure water exist in nature? Answer: Yes and No. Precipitate is pure
until it reaches the ground where soluble and insoluble substances leach
into it. It can be achieved, however, by in exchange, reverse osmosis, or
distillation.
▶ universal solvent Answer: Dissolves into anything (Water).
▶ The two types of compounds are... Answer: Molecular and Ionic
compounds
▶ Coagulation and Flocculation Answer: The purpose of this process is to
remove types of particulate impurities called: suspended solids, colloidal
matter, and dissolved solids.
▶ Flash mixing takes... Answer: about 3 to 5 seconds at the most.
▶ Suspended and collodial matter have a negative charge so.... Answer:
they naturally repel each other. This is called the ZETA Potential.
▶ When flash mixing... Answer: the lower the temperature of the water, the
less effective coagulant is. we'll have to add more chemical or allow for a
longer detention time.
, ▶ Extreme values of pH on both ends of the spectrum can interfere with
Flocculation. Answer: The correct pH balance: 5 to 7.
▶ The pH scale Answer: Starts ad 0 and ends at 14. it is used to show the
acidity of a substance or the concentration of hydronium ions
▶ Alkalinity in water is caused by.. Answer: Carbonates a d Bicarbonates
▶ Coagulants need alkalinity in water to... Answer: form flocc
▶ Alkalinity is NOT the same as pH... Answer: it is the capacity of water to
neutralize acid.
▶ The Flocculation process promotes Answer: contact between particles.
▶ ideal flocc size should be about... Answer: .1 millimeters to 3 millimeters
▶ We want detention times for Flocculation to be... Answer: 5 to 20
minutes for direct filtration. 30 minutes for conventional
▶ The purpose of the sedimentation process is to: Answer: allow flocc and
other precipitates to settle out and reduce the load on the filters,
accomplished by decreasing the velocity of water.
▶ Short Circuiting Answer: Water bypasses the flow path and reaches the
end of the basin before the normal detention time. this is unavoidable.
▶ Density Currents Answer: Is the uneven distribution of suspended solids
that reduce the performance of the bed by adding to the short Circuiting
problem.
▶ Algae and slime growth Answer: Can start to grow on the sides of a
sedimentation basin potentially causing taste and odor problems. Control
by coating the walls with copper Sulfate/ lime.
▶ Rectangular Sedimentation Basins Answer: Are usually constructed of
concrete or steel and the bottom is sloped downward so that sludge can be
easily removed.
QUESTIONS WITH ACCURATE SOLUTIONS
2026
▶ Water Intake structures Answer: Provide water to the treatment plant,
prevent large debris from entering the treatment process, and constructed
to provide pressure to the distribution system.
▶ What is pure water? Answer: Pure water is the absence of soluble and
insoluble substances in it.
▶ Can pure water exist in nature? Answer: Yes and No. Precipitate is pure
until it reaches the ground where soluble and insoluble substances leach
into it. It can be achieved, however, by in exchange, reverse osmosis, or
distillation.
▶ universal solvent Answer: Dissolves into anything (Water).
▶ The two types of compounds are... Answer: Molecular and Ionic
compounds
▶ Coagulation and Flocculation Answer: The purpose of this process is to
remove types of particulate impurities called: suspended solids, colloidal
matter, and dissolved solids.
▶ Flash mixing takes... Answer: about 3 to 5 seconds at the most.
▶ Suspended and collodial matter have a negative charge so.... Answer:
they naturally repel each other. This is called the ZETA Potential.
▶ When flash mixing... Answer: the lower the temperature of the water, the
less effective coagulant is. we'll have to add more chemical or allow for a
longer detention time.
, ▶ Extreme values of pH on both ends of the spectrum can interfere with
Flocculation. Answer: The correct pH balance: 5 to 7.
▶ The pH scale Answer: Starts ad 0 and ends at 14. it is used to show the
acidity of a substance or the concentration of hydronium ions
▶ Alkalinity in water is caused by.. Answer: Carbonates a d Bicarbonates
▶ Coagulants need alkalinity in water to... Answer: form flocc
▶ Alkalinity is NOT the same as pH... Answer: it is the capacity of water to
neutralize acid.
▶ The Flocculation process promotes Answer: contact between particles.
▶ ideal flocc size should be about... Answer: .1 millimeters to 3 millimeters
▶ We want detention times for Flocculation to be... Answer: 5 to 20
minutes for direct filtration. 30 minutes for conventional
▶ The purpose of the sedimentation process is to: Answer: allow flocc and
other precipitates to settle out and reduce the load on the filters,
accomplished by decreasing the velocity of water.
▶ Short Circuiting Answer: Water bypasses the flow path and reaches the
end of the basin before the normal detention time. this is unavoidable.
▶ Density Currents Answer: Is the uneven distribution of suspended solids
that reduce the performance of the bed by adding to the short Circuiting
problem.
▶ Algae and slime growth Answer: Can start to grow on the sides of a
sedimentation basin potentially causing taste and odor problems. Control
by coating the walls with copper Sulfate/ lime.
▶ Rectangular Sedimentation Basins Answer: Are usually constructed of
concrete or steel and the bottom is sloped downward so that sludge can be
easily removed.
