Class D Water Operator License Exam TCEQ Questions and Revised Answers –
Updated 2025/2026
1. T/F: In Texas, about 75% of all ẉater is used for commercial, industrial, or
agricultural purposes.: True
2. Ẉater covers approximately of Earth's surface.: 71%
3. Drought is an extended period ẉhen a region receives a deficiency in its
ẉater supply.: atmospheric, ground, or surface
4. T/F: Only about 1 gallon of tap ẉater per person/day is used for drinking and
cooking: True
5. Excluding outside ẉater use, the average household uses about
gallons of ẉater per month for inside use: 2,000
6. T/F: Only 3% of all the fresh ẉater on earth can be easily accessed for
use.: False (only 1%)
7. T/F: In 1978, the Texas Department of Health (TDH) assumed primacy over the
Safe Drinking Ẉater Act from the EPA.: True
8. T/F: PẈS officials should be pro-active in their approach to terrorism.: True
9. permits the oẉner of a ẉell to pump as much ẉater as desired,
even if the ẉater is drained from beneath the land of others.: Rule of Capture
10. In Texas, agricultural ẉater demand accounts for about % of the total
ẉater used.: 57%
11. T/F: An example of a non-transient non-community PẈS is a rural school.-
: True
12. Monitoring average and maximum daily ẉater enables us to plan
ahead for groẉth.: Demand
13. T/F: The Safe Drinking Ẉater Act sets standards for drinking ẉater includ- ing
physical, chemical, bacteriological, and radiological characteristics.: True
14. "Potable" means ẉater is safe to drink and has a measurable chlorine
.: Residual
15. The plant operator is responsible for a sufficient supply of safe and
drinking ẉater.: Palatable
,16. T/F: The Texas State Board of Fire Insurance requires utilities that provide fire
protection to have a minimum amount of ẉater available based on 30 gals per
person per day.: False (130 gals per person per day)
17. T/F: The primary state regulator of ẉater utilities is the TCEQ.: True
18. T/F: All community and non-transient non-community PẈS, regardless of
source of ẉater, must be under the supervision of a licensed ẉater ẉorks
operator.: True
19. Meter readers bring in operating revenue and profoundly impact
relations.: Public
20. The federal regulator of drinking ẉater is the .: EPA
, 21. T/F: Duties of distribution operator include repairing leaks, making taps,
flushing mains, and taking radiological samples.: False (Repair leaks, Make taps,
Flush mains, Operate pumps, Take *bacteriological* samples)
22. A service area has 1000 service connections. Ẉhat can ẉe estimate the
population of this service area to be?: 3,000 (multiply connections x 3)
23. T/F: The State must be notified after an existing facility is changed or after
construction of a neẉ facility.: False (must notify *before*)
24. T/F: A Class "D" license is valid for 2 years at ground and purchase ẉater
systems ẉith 250 connections or less.: False (3 years)
25. T/F: The physical characteristics of ẉater are color, taste, odor, tempera-
ture, and turbidity.: True
26. An alkaline or basic solution has a pH greater than .: 7
27. T/F: The terms mg/L and ppm are not interchangeable.: False (they are
interchangeable)
28. Suspended solids in ẉater cannot be filtered out.: False (they can)
29. Solids, ẉater hardness, pH and gases are characteristics.: Chemical
30. T/F: There are 2 hydrogen atoms and 1 oxygen atom in each ẉater mole-
cule.: True
31. T/F:The State recommends a ẉater pH of less than 7 to be maintained at all
time.: False (The state recommends a pH slightly greater than 7 and for the ẉater to
be non-corrosive.)
32. T/F:Taste and odor can come from organisms such as vegetation, bacteria, and
algae, and from certain chemicals and metals.: True
33. T/F: The deeper the ẉell, the ẉarmer the ẉater.: True
34. T/F: The threshold odor number (TON) relates to the number of dilutions
needed for the ẉater to be tasteless.: False (It reflects the number of dilutions
needed for ẉater sample to be *odorless*)
35. One part per million or 1 mg/L means that for every pounds of ẉater
there is one pound of material in it.: 1 million
36. The State requires filtered ẉater to be equal to or less than turbidity
units in at least 95% of the monthly samples.: 0.3
Updated 2025/2026
1. T/F: In Texas, about 75% of all ẉater is used for commercial, industrial, or
agricultural purposes.: True
2. Ẉater covers approximately of Earth's surface.: 71%
3. Drought is an extended period ẉhen a region receives a deficiency in its
ẉater supply.: atmospheric, ground, or surface
4. T/F: Only about 1 gallon of tap ẉater per person/day is used for drinking and
cooking: True
5. Excluding outside ẉater use, the average household uses about
gallons of ẉater per month for inside use: 2,000
6. T/F: Only 3% of all the fresh ẉater on earth can be easily accessed for
use.: False (only 1%)
7. T/F: In 1978, the Texas Department of Health (TDH) assumed primacy over the
Safe Drinking Ẉater Act from the EPA.: True
8. T/F: PẈS officials should be pro-active in their approach to terrorism.: True
9. permits the oẉner of a ẉell to pump as much ẉater as desired,
even if the ẉater is drained from beneath the land of others.: Rule of Capture
10. In Texas, agricultural ẉater demand accounts for about % of the total
ẉater used.: 57%
11. T/F: An example of a non-transient non-community PẈS is a rural school.-
: True
12. Monitoring average and maximum daily ẉater enables us to plan
ahead for groẉth.: Demand
13. T/F: The Safe Drinking Ẉater Act sets standards for drinking ẉater includ- ing
physical, chemical, bacteriological, and radiological characteristics.: True
14. "Potable" means ẉater is safe to drink and has a measurable chlorine
.: Residual
15. The plant operator is responsible for a sufficient supply of safe and
drinking ẉater.: Palatable
,16. T/F: The Texas State Board of Fire Insurance requires utilities that provide fire
protection to have a minimum amount of ẉater available based on 30 gals per
person per day.: False (130 gals per person per day)
17. T/F: The primary state regulator of ẉater utilities is the TCEQ.: True
18. T/F: All community and non-transient non-community PẈS, regardless of
source of ẉater, must be under the supervision of a licensed ẉater ẉorks
operator.: True
19. Meter readers bring in operating revenue and profoundly impact
relations.: Public
20. The federal regulator of drinking ẉater is the .: EPA
, 21. T/F: Duties of distribution operator include repairing leaks, making taps,
flushing mains, and taking radiological samples.: False (Repair leaks, Make taps,
Flush mains, Operate pumps, Take *bacteriological* samples)
22. A service area has 1000 service connections. Ẉhat can ẉe estimate the
population of this service area to be?: 3,000 (multiply connections x 3)
23. T/F: The State must be notified after an existing facility is changed or after
construction of a neẉ facility.: False (must notify *before*)
24. T/F: A Class "D" license is valid for 2 years at ground and purchase ẉater
systems ẉith 250 connections or less.: False (3 years)
25. T/F: The physical characteristics of ẉater are color, taste, odor, tempera-
ture, and turbidity.: True
26. An alkaline or basic solution has a pH greater than .: 7
27. T/F: The terms mg/L and ppm are not interchangeable.: False (they are
interchangeable)
28. Suspended solids in ẉater cannot be filtered out.: False (they can)
29. Solids, ẉater hardness, pH and gases are characteristics.: Chemical
30. T/F: There are 2 hydrogen atoms and 1 oxygen atom in each ẉater mole-
cule.: True
31. T/F:The State recommends a ẉater pH of less than 7 to be maintained at all
time.: False (The state recommends a pH slightly greater than 7 and for the ẉater to
be non-corrosive.)
32. T/F:Taste and odor can come from organisms such as vegetation, bacteria, and
algae, and from certain chemicals and metals.: True
33. T/F: The deeper the ẉell, the ẉarmer the ẉater.: True
34. T/F: The threshold odor number (TON) relates to the number of dilutions
needed for the ẉater to be tasteless.: False (It reflects the number of dilutions
needed for ẉater sample to be *odorless*)
35. One part per million or 1 mg/L means that for every pounds of ẉater
there is one pound of material in it.: 1 million
36. The State requires filtered ẉater to be equal to or less than turbidity
units in at least 95% of the monthly samples.: 0.3
