NASCLA Accredited Commercial General ContractorSite WorkEasy
A contractor is installing a new storm drain system on a commercial development site. The design calls for a series of catch basins and underground pipes. Which of the following is the primary purpose of a catch basin in a storm drainage system?
- ATo increase the velocity of stormwater flow within the pipes.
- BTo collect surface runoff and prevent debris from entering the pipe system.
- CTo filter pollutants from stormwater before it enters the pipes.
- DTo store excess stormwater during heavy rainfall events.
Show answer & explanationAnswer & explanation
Correct answer: B. To collect surface runoff and prevent debris from entering the pipe system.
Catch basins are designed to intercept surface runoff and direct it into the underground storm sewer system. They typically include a sump or trap to settle out sediments and capture debris, preventing blockages in the piping.
Why the other options are wrong
- A. Catch basins can actually reduce flow velocity due to turbulence and changes in direction, they do not increase it.
- C. While some catch basins may have minor filtering capabilities, their primary role is not pollution filtration; that's typically handled by specialized stormwater quality units.
- D. Detention or retention basins are designed for stormwater storage, not catch basins.
Catch Basin
A component of a storm drainage system that collects surface runoff and channels it into an underground pipe network, typically featuring a sump to trap sediment and debris.
- Collects surface water.
- Prevents debris from entering pipes.
- Often includes a sump for sediment accumulation.
Memory trick: Catch the Rain, Drain the Debris, Store the Excess.