What is a common characteristic of scupper drains?

Scupper drains are specifically designed to manage stormwater by providing an outlet that allows excess water to drain away efficiently. This function is essential in preventing water accumulation, which can lead to flooding or water damage, especially in outdoor and roof applications. Scuppers are typically integrated into the design of buildings and structures to direct water away from critical areas and into a drainage system, making them vital for effective stormwater management.

The other options represent functions or applications that do not typically align with the primary role of scupper drains. While their proximity to downspouts might be noted in specific designs, it does not characterize the drains themselves. Similarly, venting trapped air in pipes relates more to plumbing fixtures rather than drainage systems, and scupper drains are not primarily limited to residential plumbing—they are frequently utilized in commercial and municipal applications as well.