CPESC Stormwater Management 4

Question 1

What does the term 'impervious cover' refer to in stormwater management?

Accepted Answer

Surfaces that prevent or severely limit infiltration of water into soil

Answer

Impervious cover includes surfaces like pavement, rooftops, and compacted areas that prevent rainfall infiltration, increasing runoff volume and peak flows.

Question 2

A stormwater retention pond differs from a detention pond in that a retention pond:

Accepted Answer

Maintains a permanent pool of water between storm events

Answer

Retention ponds maintain a permanent water pool that provides treatment through settling and biological uptake, while detention ponds drain completely between storms.

Question 3

Under post-construction stormwater regulations, what is the typical maximum drawdown time for extended detention facilities treating the water quality volume?

Accepted Answer

48 hours

Answer

Extended detention facilities are typically designed to release the water quality volume over 24-48 hours to promote settling of fine particles.

Question 4

Which best management practice (BMP) is specifically designed to remove sediment from stormwater through gravity settling in a confined area before discharge?

Accepted Answer

Sediment forebay

Answer

A sediment forebay is a pretreatment cell at the inlet of a stormwater BMP designed to capture coarse sediment through gravity settling.

Question 5

The term 'water quality volume' (WQv) typically represents runoff from which storm size?

Accepted Answer

A small, frequently occurring storm (e.g., 1-inch or 90th percentile)

Answer

Water quality volume is sized to capture the runoff from small, frequent storms (often 1-inch or the 90th percentile event) that carry the majority of annual pollutant loads.

(CPESC) Certified Professional in Erosion and Sediment Control Practice Test

(CPESC) Certified Professional in Erosion and Sediment Control Practice Test

CPESC Stormwater Management 4