Class D Water Operator License Exam TCEQ Newest
2026/2027 Questions and Correct Detailed Answers
Already Graded A+
If there is no chlorine ______ at a faucet, do not sample, flush longer. -
CORRECT ANSWER-residual
T/F: All repeat samples must be collected on successive days. - CORRECT
ANSWER-False (Collect all repeat sample on the same day)
In the event of distribution pressure below ___ psi, _______ outages, repeated
bad samples or chlorine _____ below minimum, special precautions must be
instituted. - CORRECT ANSWER-20/water/residual
Get the sample to the lab within ___________ or it will be rejected. - CORRECT
ANSWER-30 hours (for BacT samples)
At 0.8 - 1.0 mg/L, fluoride reduces dental cavities, but in higher doeses (>2.0
mg/L) can cause _____ of teeth over time. - CORRECT ANSWER-mottling
,T/F: One by-product of chlorinated drinking water is trihalomethane, a suspected
carcinogen. - CORRECT ANSWER-True
T/F: In Texas, about 75% of all water is used for commercial, industrial, or
agricultural purposes. - CORRECT ANSWER-True
Water covers approximately ________ of Earth's surface. - CORRECT ANSWER-
71%
Drought is an extended period when a region receives a deficiency in its ________
water supply. - CORRECT ANSWER-atmospheric, ground, or surface
T/F: Only about 1 gallon of tap water per person/day is used for drinking and
cooking - CORRECT ANSWER-True
Excluding outside water use, the average household uses about _______ gallons
of water per month for inside use - CORRECT ANSWER-2,000
T/F: Only 3% of all the fresh water on earth can be easily accessed for use. -
CORRECT ANSWER-False (only 1%)
,T/F: In 1978, the Texas Department of Health (TDH) assumed primacy over the
Safe Drinking Water Act from the EPA. - CORRECT ANSWER-True
T/F: PWS officials should be pro-active in their approach to terrorism. -
CORRECT ANSWER-True
_________ permits the owner of a well to pump as much water as desired, even if
the water is drained from beneath the land of others. - CORRECT ANSWER-
Rule of Capture
In Texas, agricultural water demand accounts for about ___% of the total water
used. - CORRECT ANSWER-57%
T/F: An example of a non-transient non-community PWS is a rural school. -
CORRECT ANSWER-True
Monitoring average and maximum daily water ______ enables us to plan ahead
for growth. - CORRECT ANSWER-Demand
, T/F: The Safe Drinking Water Act sets standards for drinking water including
physical, chemical, bacteriological, and radiological characteristics. - CORRECT
ANSWER-True
"Potable" means water is safe to drink and has a measurable chlorine ________. -
CORRECT ANSWER-Residual
The plant operator is responsible for a sufficient supply of safe and ________
drinking water. - CORRECT ANSWER-Palatable
T/F: The Texas State Board of Fire Insurance requires utilities that provide fire
protection to have a minimum amount of water available based on 30 gals per
person per day. - CORRECT ANSWER-False (130 gals per person per day)
T/F: The primary state regulator of water utilities is the TCEQ. - CORRECT
ANSWER-True
T/F: All community and non-transient non-community PWS, regardless of source
of water, must be under the supervision of a licensed water works operator. -
CORRECT ANSWER-True
2026/2027 Questions and Correct Detailed Answers
Already Graded A+
If there is no chlorine ______ at a faucet, do not sample, flush longer. -
CORRECT ANSWER-residual
T/F: All repeat samples must be collected on successive days. - CORRECT
ANSWER-False (Collect all repeat sample on the same day)
In the event of distribution pressure below ___ psi, _______ outages, repeated
bad samples or chlorine _____ below minimum, special precautions must be
instituted. - CORRECT ANSWER-20/water/residual
Get the sample to the lab within ___________ or it will be rejected. - CORRECT
ANSWER-30 hours (for BacT samples)
At 0.8 - 1.0 mg/L, fluoride reduces dental cavities, but in higher doeses (>2.0
mg/L) can cause _____ of teeth over time. - CORRECT ANSWER-mottling
,T/F: One by-product of chlorinated drinking water is trihalomethane, a suspected
carcinogen. - CORRECT ANSWER-True
T/F: In Texas, about 75% of all water is used for commercial, industrial, or
agricultural purposes. - CORRECT ANSWER-True
Water covers approximately ________ of Earth's surface. - CORRECT ANSWER-
71%
Drought is an extended period when a region receives a deficiency in its ________
water supply. - CORRECT ANSWER-atmospheric, ground, or surface
T/F: Only about 1 gallon of tap water per person/day is used for drinking and
cooking - CORRECT ANSWER-True
Excluding outside water use, the average household uses about _______ gallons
of water per month for inside use - CORRECT ANSWER-2,000
T/F: Only 3% of all the fresh water on earth can be easily accessed for use. -
CORRECT ANSWER-False (only 1%)
,T/F: In 1978, the Texas Department of Health (TDH) assumed primacy over the
Safe Drinking Water Act from the EPA. - CORRECT ANSWER-True
T/F: PWS officials should be pro-active in their approach to terrorism. -
CORRECT ANSWER-True
_________ permits the owner of a well to pump as much water as desired, even if
the water is drained from beneath the land of others. - CORRECT ANSWER-
Rule of Capture
In Texas, agricultural water demand accounts for about ___% of the total water
used. - CORRECT ANSWER-57%
T/F: An example of a non-transient non-community PWS is a rural school. -
CORRECT ANSWER-True
Monitoring average and maximum daily water ______ enables us to plan ahead
for growth. - CORRECT ANSWER-Demand
, T/F: The Safe Drinking Water Act sets standards for drinking water including
physical, chemical, bacteriological, and radiological characteristics. - CORRECT
ANSWER-True
"Potable" means water is safe to drink and has a measurable chlorine ________. -
CORRECT ANSWER-Residual
The plant operator is responsible for a sufficient supply of safe and ________
drinking water. - CORRECT ANSWER-Palatable
T/F: The Texas State Board of Fire Insurance requires utilities that provide fire
protection to have a minimum amount of water available based on 30 gals per
person per day. - CORRECT ANSWER-False (130 gals per person per day)
T/F: The primary state regulator of water utilities is the TCEQ. - CORRECT
ANSWER-True
T/F: All community and non-transient non-community PWS, regardless of source
of water, must be under the supervision of a licensed water works operator. -
CORRECT ANSWER-True
