Definition - What does Sewer Plug mean?
A sewer plug is a barrier inserted into a sanitary sewer line undergoing rehabilitation or repair to prevent flow into work areas. Plugs are manufactured in standard sewer pipe sizes to fit snugly into standard-sized pipes. There are also inflatable plugs that, when inflated with compressed air, expand to create a dam that blocks the line.
Trenchlesspedia explains Sewer Plug
Sewer dams are inserted in a line before rehabilitation begins. They are located before (based on the direction of flow) the part of the pipe that is damaged or scheduled for rehabilitation.. A hole is created in the top of the sewer pipe wall of the pipe. The plug is inserted in the pipe and sewage is then contained. Any sewage remaining in the line past the dam's location is drained. Repairs are then made to the sewer line or a bypass line is created, allowing sewage to bypass the afflicted portion of the sewer line. When the rehabilitation project is complete or the bypass line is connected, the plug is removed and the hole in the top of the pipe repaired.