CPWM Utility Systems 2

Question 1

Which type of water main valve is BEST suited for throttling flow in a distribution system?

Accepted Answer

Globe valve

Answer

Globe valves are designed for throttling because their internal disk allows precise flow regulation, unlike gate valves which are intended only for full open/close operation.

Question 2

A public works manager notices elevated trihalomethane (THM) levels in the distribution system. What is the MOST likely cause?

Accepted Answer

Chlorine reacting with organic matter

Answer

Trihalomethanes form when disinfectants like chlorine react with naturally occurring organic matter in the water supply.

Question 3

Under the Clean Water Act, a municipal wastewater treatment plant discharging to a river must obtain a:

Accepted Answer

NPDES permit

Answer

The National Pollutant Discharge Elimination System (NPDES) permit is required under the Clean Water Act for any point source discharge to navigable waters.

Question 4

What is the primary purpose of a wet well in a wastewater lift station?

Accepted Answer

To store influent and provide a buffer for pump cycling

Answer

The wet well collects incoming wastewater and provides storage volume that allows pumps to cycle on and off efficiently rather than running continuously.

Question 5

Which pipe material is MOST resistant to corrosion in highly acidic soils for buried water mains?

Accepted Answer

PVC (polyvinyl chloride)

Answer

PVC is chemically inert and does not corrode in acidic soil environments, making it superior to iron or steel in corrosive soil conditions.

(CPWM) Certified Public Works Manager Practice Test

(CPWM) Certified Public Works Manager Practice Test

CPWM Utility Systems 2