CPII Drainage & Stormwater Management 2

Question 1

What does the Manning's equation primarily calculate in open-channel drainage design?

Accepted Answer

The flow velocity and discharge in an open channel

Answer

Manning's equation is used to calculate flow velocity and volumetric discharge in open channels based on channel geometry, slope, and roughness.

Question 2

An inspector finds that a roadside drainage ditch has experienced severe erosion and channel widening. Which BMP would BEST stabilize the channel long-term?

Accepted Answer

Lining the channel with riprap or seeding with erosion-resistant vegetation

Answer

Riprap lining or erosion-resistant vegetation provides durable channel bank protection against hydraulic shear forces that cause erosion.

Question 3

In drainage infrastructure, what is the primary difference between a retention pond and a detention pond?

Accepted Answer

Retention ponds hold a permanent pool of water; detention ponds drain completely between storms

Answer

A retention pond maintains a permanent pool of water and provides water quality treatment, while a detention pond is dry between storm events and controls only peak flow.

Question 4

When inspecting a reinforced concrete pipe (RCP) storm drain, which defect classification indicates the pipe requires immediate action?

Accepted Answer

Full circumferential cracking with active leakage and soil intrusion

Answer

Full circumferential cracking with active leakage and soil intrusion indicates imminent structural failure requiring immediate repair or replacement.

Question 5

What is the purpose of a check dam installed in a drainage swale or channel?

Accepted Answer

To reduce flow velocity and promote sediment deposition upstream

Answer

Check dams reduce flow velocity, which allows suspended sediment to settle out and prevents channel erosion downstream.

(CPII) Certified Public Infrastructure Inspector Practice Test

(CPII) Certified Public Infrastructure Inspector Practice Test

CPII Drainage & Stormwater Management 2