Storm Water Pollution Prevention Plan (SWPPP) Practice Test

What is the purpose of storm drain inlet protection?

1. To prevent debris from entering storm drains

2. To pond water and allow sediment to settle out

3. To enhance water drainage efficiency

4. To filter pollutants from runoff water

The correct answer is: To pond water and allow sediment to settle out

The purpose of storm drain inlet protection is primarily to prevent debris from entering storm drains and to manage sediment in the stormwater system. The correct choice highlights the function of allowing water to pond at the inlet, which creates conditions favorable for sediment to settle out before runoff enters the drainage system. This is essential because excessive sediment can clog drains and can also lead to increased pollution and degradation of nearby water bodies. Ponding helps reduce the velocity of the incoming water, allowing particulates to settle out instead of flowing directly into the storm drain, where they can contribute to downstream water quality issues. While filtering pollutants and enhancing drainage efficiency are important aspects of stormwater management, the primary function of inlet protection is to manage and trap sediment and debris right at the point where runoff enters the storm system.