What Is a Drainage Box?

Drainage Box Defined

• A drainage box, or drain box, works as part of the anti-clogging approach in plumbing. Many include a filter in a box-shaped compartment with junctions on the sides of the box for pipes to connect to. The inflow pipe is installed at a higher altitude than the outflow pipe to assist gravity flow of the water. The top opens so material can be manually removed if necessary.

Commercial Applications

• In large building and commercial applications, drainage boxes tend to be formed as large concrete boxes or culverts reinforced with re-bar. This allows a sudden flow of water drainage to be controlled and diverted away from the bottom of buildings. Many of the parts are pre-casted for easy installation during construction.

Problems with Drain Boxes

• Drainage boxes don't take care of themselves. While they help with the flow of water to central plumbing and the nearby sewer system, boxes will build up sediment and gunk over time. As a result, they periodically need to be cleaned out by hand every few years to stop buildup from causing a blockage and an eventual flooding in the box area.