CME CME Water & Wastewater Systems 3

Question 1

What is the primary goal of water main flushing programs in municipal distribution systems?

Accepted Answer

Remove sediment, biofilm, and disinfection byproducts to maintain water quality

Answer

Test pump station capacity

Answer

Reduce system pressure

Answer

Test for cross-connections

Question 2

Which type of valve is most commonly used for isolation of water mains to allow repairs or shutdowns?

Accepted Answer

Gate valve or resilient-seated gate valve

Answer

Butterfly valve

Answer

Check valve

Answer

Pressure reducing valve (PRV)

Question 3

What is biological nutrient removal (BNR) designed to eliminate from wastewater effluent?

Accepted Answer

Nitrogen and phosphorus that cause eutrophication

Answer

Heavy metals and toxics

Answer

Pathogens and bacteria

Answer

Total dissolved solids

Question 4

What is the function of a pressure reducing valve (PRV) in a water distribution system?

Accepted Answer

Reduce higher upstream pressure to a lower, controlled downstream pressure

Answer

Prevent water hammer

Answer

Boost pressure in low-pressure zones

Answer

Measure flow rate

Question 5

Under the Clean Water Act Section 404, what is required before placing fill material in US waters and wetlands for municipal infrastructure projects?

Accepted Answer

Section 404 permit from the US Army Corps of Engineers

Answer

NPDES wastewater discharge permit

Answer

Clean Air Act permit

Answer

FEMA floodplain development permit

Question 6

What is 'water age' in distribution system modeling and why is it important?

Accepted Answer

The time water has spent in the distribution system, affecting disinfectant residual and water quality

Answer

Age of the pipe infrastructure

Answer

Years since the last main replacement

Answer

Duration of a boil-water advisory