Definition - What does Bypass Plug mean?
A bypass plug is utilized in order to divert the flow of water or effluent while rehabilitation or construction takes place. Bypass plugs may be removed on a daily basis after work is completed or it may be left in place for several weeks during extensive repairs, replacement projects or construction.
Trenchlesspedia explains Bypass Plug
The use of a bypass plug is an alternate solution to using a pump that would need to be observed at all times to keep the pipe dry. In order to ensure an optimal fit, many plugs are of the pneumatic type which are inflated in place to provide the bypass. Epoxy may also be used with the plug and cured as a more permanent solution which can then be drilled through and removed when work is completed.