CWEA Collection System Maintenance GUIDE WITH
VERIFIED ANSWERS 22025/2026 Q&A |INSTANT
DOWNLOAD PDF
1. Which of the following is the primary purpose of a wastewater collection
system?
A. Generate electricity
B. Transport sewage to treatment plants
C. Provide drinking water
D. Store stormwater temporarily
*Answer: B. Transport sewage to treatment plants – The main purpose of
collection systems is to safely convey sewage from homes and businesses to
treatment facilities.
2. What is the recommended slope for a gravity sewer to prevent blockages?
A. 0.1%
B. 0.5–2%
C. 5–10%
D. 10–20%
*Answer: B. 0.5–2% – Proper slope ensures adequate velocity to move solids
without causing excessive flow velocity that can erode pipes.
3. Which type of sewer is designed to carry only stormwater?
A. Sanitary sewer
B. Combined sewer
C. Storm sewer
D. Force main
*Answer: C. Storm sewer – Storm sewers handle runoff from rainfall and prevent
flooding in urban areas.
4. What is the main reason for using manholes in sewer systems?
A. Allow inspection and maintenance
B. Increase flow velocity
,C. Store sewage temporarily
D. Divert water to streams
*Answer: A. Allow inspection and maintenance – Manholes provide access for
cleaning, inspection, and maintenance operations.
5. Which material is commonly used for gravity sewer pipes?
A. Concrete
B. Steel
C. PVC
D. Both A and C
*Answer: D. Both A and C – Concrete and PVC are widely used due to durability,
cost, and resistance to corrosion.
6. What is the function of a lift station in a collection system?
A. Reduce solids in wastewater
B. Pump sewage from lower to higher elevation
C. Treat wastewater biologically
D. Remove grease and debris
*Answer: B. Pump sewage from lower to higher elevation – Lift stations allow
sewage to flow uphill to reach the main treatment plant.
7. Which of the following can cause sewer backups?
A. Grease accumulation
B. Tree root intrusion
C. Pipe collapse
D. All of the above
*Answer: D. All of the above – Blockages and structural failures in sewer systems
are common causes of backups.
8. What is the purpose of sewer flushing?
A. Increase flow velocity
B. Clean debris and sediment from pipes
C. Test pipe durability
D. Reduce pipe diameter
, *Answer: B. Clean debris and sediment from pipes – Flushing helps maintain
unobstructed flow in the system.
9. What safety equipment is essential when entering a confined sewer space?
A. Hard hat and gloves
B. Gas monitor and harness
C. Safety glasses
D. Rubber boots only
*Answer: B. Gas monitor and harness – Confined spaces may contain toxic gases;
monitoring and fall protection are critical.
10. Which type of pump is typically used in a lift station?
A. Centrifugal pump
B. Reciprocating pump
C. Diaphragm pump
D. Gear pump
*Answer: A. Centrifugal pump – Centrifugal pumps are efficient for moving large
volumes of wastewater.
11. What is a common cause of inflow and infiltration (I&I) in sewer systems?
A. Cracked pipes
B. Faulty manhole covers
C. Illegal connections
D. All of the above
*Answer: D. All of the above – I&I occurs when stormwater enters the sewer
through cracks, leaks, or unauthorized connections.
12. Why is grease management important in collection systems?
A. Prevent pipe corrosion
B. Reduce blockages and backups
C. Improve water quality
D. Increase flow velocity
*Answer: B. Reduce blockages and backups – Grease solidifies in pipes, leading to
clogs and sanitary sewer overflows.
VERIFIED ANSWERS 22025/2026 Q&A |INSTANT
DOWNLOAD PDF
1. Which of the following is the primary purpose of a wastewater collection
system?
A. Generate electricity
B. Transport sewage to treatment plants
C. Provide drinking water
D. Store stormwater temporarily
*Answer: B. Transport sewage to treatment plants – The main purpose of
collection systems is to safely convey sewage from homes and businesses to
treatment facilities.
2. What is the recommended slope for a gravity sewer to prevent blockages?
A. 0.1%
B. 0.5–2%
C. 5–10%
D. 10–20%
*Answer: B. 0.5–2% – Proper slope ensures adequate velocity to move solids
without causing excessive flow velocity that can erode pipes.
3. Which type of sewer is designed to carry only stormwater?
A. Sanitary sewer
B. Combined sewer
C. Storm sewer
D. Force main
*Answer: C. Storm sewer – Storm sewers handle runoff from rainfall and prevent
flooding in urban areas.
4. What is the main reason for using manholes in sewer systems?
A. Allow inspection and maintenance
B. Increase flow velocity
,C. Store sewage temporarily
D. Divert water to streams
*Answer: A. Allow inspection and maintenance – Manholes provide access for
cleaning, inspection, and maintenance operations.
5. Which material is commonly used for gravity sewer pipes?
A. Concrete
B. Steel
C. PVC
D. Both A and C
*Answer: D. Both A and C – Concrete and PVC are widely used due to durability,
cost, and resistance to corrosion.
6. What is the function of a lift station in a collection system?
A. Reduce solids in wastewater
B. Pump sewage from lower to higher elevation
C. Treat wastewater biologically
D. Remove grease and debris
*Answer: B. Pump sewage from lower to higher elevation – Lift stations allow
sewage to flow uphill to reach the main treatment plant.
7. Which of the following can cause sewer backups?
A. Grease accumulation
B. Tree root intrusion
C. Pipe collapse
D. All of the above
*Answer: D. All of the above – Blockages and structural failures in sewer systems
are common causes of backups.
8. What is the purpose of sewer flushing?
A. Increase flow velocity
B. Clean debris and sediment from pipes
C. Test pipe durability
D. Reduce pipe diameter
, *Answer: B. Clean debris and sediment from pipes – Flushing helps maintain
unobstructed flow in the system.
9. What safety equipment is essential when entering a confined sewer space?
A. Hard hat and gloves
B. Gas monitor and harness
C. Safety glasses
D. Rubber boots only
*Answer: B. Gas monitor and harness – Confined spaces may contain toxic gases;
monitoring and fall protection are critical.
10. Which type of pump is typically used in a lift station?
A. Centrifugal pump
B. Reciprocating pump
C. Diaphragm pump
D. Gear pump
*Answer: A. Centrifugal pump – Centrifugal pumps are efficient for moving large
volumes of wastewater.
11. What is a common cause of inflow and infiltration (I&I) in sewer systems?
A. Cracked pipes
B. Faulty manhole covers
C. Illegal connections
D. All of the above
*Answer: D. All of the above – I&I occurs when stormwater enters the sewer
through cracks, leaks, or unauthorized connections.
12. Why is grease management important in collection systems?
A. Prevent pipe corrosion
B. Reduce blockages and backups
C. Improve water quality
D. Increase flow velocity
*Answer: B. Reduce blockages and backups – Grease solidifies in pipes, leading to
clogs and sanitary sewer overflows.
