Newest TCEQ Class D Water Operator License Practice Exam (2025–2026) with
correct answers A+ Graded period
1. The primary purpose of a public water system is to:
A. Generate electricity
B. Provide safe and potable drinking water
C. Produce wastewater
D. Irrigate crops only
✅ Answer: B
Rationale: A public water system supplies safe drinking water that meets regulatory standards.
2. "Potable water" means water that is:
A. Salty
B. Safe for human consumption
C. Used only for irrigation
D. Untreated
✅ Answer: B
3. Which federal law protects public drinking water quality?
A. Clean Air Act
B. Safe Drinking Water Act (SDWA)
C. Clean Water Act
D. Resource Conservation and Recovery Act
✅ Answer: B
,4. Which agency regulates public drinking water in Texas?
A. EPA only
B. Texas Commission on Environmental Quality (TCEQ)
C. OSHA
D. FEMA
✅ Answer: B
5. The main purpose of chlorination is to:
A. Increase hardness
B. Kill disease-causing microorganisms
C. Raise turbidity
D. Remove iron
✅ Answer: B
6. Which disinfectant residual helps protect water in the distribution system?
A. Chlorine residual
B. Iron
C. Calcium
D. Turbidity
✅ Answer: A
7. Turbidity measures:
,A. Water temperature
B. Water cloudiness
C. Water pressure
D. Water hardness
✅ Answer: B
8. High turbidity may indicate:
A. Suspended particles
B. High chlorine residual
C. High water pressure
D. Low alkalinity
✅ Answer: A
9. Which instrument measures chlorine residual?
A. Colorimeter
B. Thermometer
C. Flow meter
D. Pressure gauge
✅ Answer: A
10. Which water quality characteristic affects taste and odor?
A. Physical characteristics
B. Electrical conductivity only
, C. Pipe size
D. Pump horsepower
✅ Answer: A
11. Groundwater is generally obtained from:
A. Rivers
B. Lakes
C. Wells
D. Reservoir spillways
✅ Answer: C
12. Surface water sources include:
A. Wells only
B. Rivers, lakes, and reservoirs
C. Aquifers only
D. Springs only
✅ Answer: B
13. The primary function of a well casing is to:
A. Increase water pressure
B. Prevent contamination and support the borehole
C. Increase chlorine residual
D. Remove bacteria
correct answers A+ Graded period
1. The primary purpose of a public water system is to:
A. Generate electricity
B. Provide safe and potable drinking water
C. Produce wastewater
D. Irrigate crops only
✅ Answer: B
Rationale: A public water system supplies safe drinking water that meets regulatory standards.
2. "Potable water" means water that is:
A. Salty
B. Safe for human consumption
C. Used only for irrigation
D. Untreated
✅ Answer: B
3. Which federal law protects public drinking water quality?
A. Clean Air Act
B. Safe Drinking Water Act (SDWA)
C. Clean Water Act
D. Resource Conservation and Recovery Act
✅ Answer: B
,4. Which agency regulates public drinking water in Texas?
A. EPA only
B. Texas Commission on Environmental Quality (TCEQ)
C. OSHA
D. FEMA
✅ Answer: B
5. The main purpose of chlorination is to:
A. Increase hardness
B. Kill disease-causing microorganisms
C. Raise turbidity
D. Remove iron
✅ Answer: B
6. Which disinfectant residual helps protect water in the distribution system?
A. Chlorine residual
B. Iron
C. Calcium
D. Turbidity
✅ Answer: A
7. Turbidity measures:
,A. Water temperature
B. Water cloudiness
C. Water pressure
D. Water hardness
✅ Answer: B
8. High turbidity may indicate:
A. Suspended particles
B. High chlorine residual
C. High water pressure
D. Low alkalinity
✅ Answer: A
9. Which instrument measures chlorine residual?
A. Colorimeter
B. Thermometer
C. Flow meter
D. Pressure gauge
✅ Answer: A
10. Which water quality characteristic affects taste and odor?
A. Physical characteristics
B. Electrical conductivity only
, C. Pipe size
D. Pump horsepower
✅ Answer: A
11. Groundwater is generally obtained from:
A. Rivers
B. Lakes
C. Wells
D. Reservoir spillways
✅ Answer: C
12. Surface water sources include:
A. Wells only
B. Rivers, lakes, and reservoirs
C. Aquifers only
D. Springs only
✅ Answer: B
13. The primary function of a well casing is to:
A. Increase water pressure
B. Prevent contamination and support the borehole
C. Increase chlorine residual
D. Remove bacteria
