CPD CPD Storm Drainage & Site Utilities

Question 1

What is the primary purpose of a storm drainage system in a building site design?

Accepted Answer

To convey rainwater and surface runoff away from structures to prevent flooding

Answer

To supply potable water to fire suppression systems

Answer

To manage sanitary sewage from restrooms and kitchens

Answer

To circulate chilled water through HVAC coils

Question 2

Which hydraulic method is most commonly used to size storm drainage piping in the US?

Accepted Answer

Manning's equation for open-channel flow

Answer

Bernoulli's principle for pressurized flow

Answer

Hazen-Williams formula for velocity head

Answer

Darcy-Weisbach equation for laminar flow

Question 3

What is the 'rational method' used for in storm drainage design?

Accepted Answer

Estimating peak stormwater runoff from a drainage area

Answer

Calculating pipe friction losses under pressure flow

Answer

Determining the pH balance of stormwater discharge

Answer

Sizing sump pump horsepower requirements

Question 4

Which coefficient in the rational method accounts for the type of surface (e.g., pavement vs. lawn)?

Accepted Answer

Runoff coefficient (C)

Answer

Rainfall intensity (i)

Answer

Drainage area (A)

Answer

Manning's roughness (n)

Question 5

What is the function of a catch basin in a site storm drainage system?

Accepted Answer

To collect surface runoff and remove debris before it enters underground piping

Answer

To store potable water for emergency irrigation use

Answer

To equalize pressure between storm and sanitary sewer lines

Answer

To filter sediment from domestic hot water systems

Question 6

Per IPC and most US plumbing codes, what minimum slope is typically required for horizontal storm drainage piping 3 inches in diameter?

Accepted Answer

1/4 inch per foot

Answer

1/8 inch per foot

Answer

1/2 inch per foot

Answer

1 inch per foot