Water Plant Operator Certification Exam
Prep – AWWA UPDATED Exam Questions
and CORRECT Answers
What is the area of a circular clarifier in Ft^2 if it has a diameter of 125 ft? - CORRECT
ANSWER
What is the surface loading rate for a sedimentation basin that is 125 ft by 68 ft if it is treating an
instantaneous flow of 4.75 ft^3/s - CORRECT ANSWER
What is the most common disinfection by product when adding chlorine to water containing
natural and inorganic matter? - CORRECT ANSWER
What is the velocity of flow in ft/s for a diameter pipe if it delivers 178 gpm? - CORRECT
ANSWER
what will most probabaly cause taste and odors, slime and filter clogging? - CORRECT
ANSWER
Why can rapid sand filters handle higher filtration rate compared to slow sand filters -
CORRECT ANSWER
What should the chemical feeder setting be in mL/min for a polymer soulution if the desired
dosage is 3.50 mg/l and the treatment plant is treating 13.7 mgd? The specific gravity of the
polymer is 1.28. - CORRECT ANSWER
Iron bacteria can interfere with ________________ because the bacteria produce _________ that
prevents the stabilization chemicals from reaching the pipe surface. - CORRECT
ANSWER
, Hypochlorus acideis favored over hypochlorite ion when the pH is _________ and the
temperature is __________. - CORRECT ANSWER
What filter has an unstratified media distribution? - CORRECT ANSWER
A well produces 97 gpm. If the drawdown for the well is 22ft, What is the specific yield in
gpm/ft? - CORRECT ANSWER
What is(are) the combined chlorine residual(s) at pH values ranging form 6.5 to 8.5? -
CORRECT ANSWER
If the total hardness of a water sample is 97 mg/L as CaCO3 and the calcium hardness is 81
mg/L as CaCo3, what is the magnesium hardness - CORRECT ANSWER
When iron alone is treated using manganese greensand filters, the chlorine feed rate should be
about _______. - CORRECT ANSWER
Chlorination of water that has high concentration of natural organic matter will produce. -
CORRECT ANSWER
When disinfecting with chloramines, when can the ammonia be added to the process? -
CORRECT ANSWER
What will settle out of the water in a short period of time? - CORRECT ANSWER
Point-of-use activated carbon filters are most effective for removing__________. - CORRECT
ANSWER
Potassium permanganate is used as an oxidant for control of ____________. - CORRECT
ANSWER
Prep – AWWA UPDATED Exam Questions
and CORRECT Answers
What is the area of a circular clarifier in Ft^2 if it has a diameter of 125 ft? - CORRECT
ANSWER
What is the surface loading rate for a sedimentation basin that is 125 ft by 68 ft if it is treating an
instantaneous flow of 4.75 ft^3/s - CORRECT ANSWER
What is the most common disinfection by product when adding chlorine to water containing
natural and inorganic matter? - CORRECT ANSWER
What is the velocity of flow in ft/s for a diameter pipe if it delivers 178 gpm? - CORRECT
ANSWER
what will most probabaly cause taste and odors, slime and filter clogging? - CORRECT
ANSWER
Why can rapid sand filters handle higher filtration rate compared to slow sand filters -
CORRECT ANSWER
What should the chemical feeder setting be in mL/min for a polymer soulution if the desired
dosage is 3.50 mg/l and the treatment plant is treating 13.7 mgd? The specific gravity of the
polymer is 1.28. - CORRECT ANSWER
Iron bacteria can interfere with ________________ because the bacteria produce _________ that
prevents the stabilization chemicals from reaching the pipe surface. - CORRECT
ANSWER
, Hypochlorus acideis favored over hypochlorite ion when the pH is _________ and the
temperature is __________. - CORRECT ANSWER
What filter has an unstratified media distribution? - CORRECT ANSWER
A well produces 97 gpm. If the drawdown for the well is 22ft, What is the specific yield in
gpm/ft? - CORRECT ANSWER
What is(are) the combined chlorine residual(s) at pH values ranging form 6.5 to 8.5? -
CORRECT ANSWER
If the total hardness of a water sample is 97 mg/L as CaCO3 and the calcium hardness is 81
mg/L as CaCo3, what is the magnesium hardness - CORRECT ANSWER
When iron alone is treated using manganese greensand filters, the chlorine feed rate should be
about _______. - CORRECT ANSWER
Chlorination of water that has high concentration of natural organic matter will produce. -
CORRECT ANSWER
When disinfecting with chloramines, when can the ammonia be added to the process? -
CORRECT ANSWER
What will settle out of the water in a short period of time? - CORRECT ANSWER
Point-of-use activated carbon filters are most effective for removing__________. - CORRECT
ANSWER
Potassium permanganate is used as an oxidant for control of ____________. - CORRECT
ANSWER
