No Service Interruptions
October 21, 2008
What if you couldn’t use your sink, shower, toilet or washing machine for six months? Well, thankfully, this won’t have to happen during the replacement of the Lake Oswego Interceptor Sewer (LOIS). The project has been designed so that essential sewer service will continue uninterrupted throughout the project. Thanks to ‘bypass pumping,’ residents can go about their daily lives without sewer interruption.
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| An example of a bypass sewer set up in downtown Portland |
Bypass pumping will be needed during the lake down work as manholes are being worked on. The contractor will disconnect the existing sewer line and pump the contents to a separate bypass sewer line. This allows the contractor to upgrade an existing sewer manhole or install or connect a new segment of pipe to a manhole while allowing sewer flows to continue.
Here is a simplified explanation of the bypass pumping process:
- First, the contractor fuses or bolts together a short suction pipe that goes into a manhole upstream of the manhole where work is being done.
- A long discharge pipe is fused or bolted together and goes into a manhole downstream of the work area.
- The piping is attached to the pumps.
- When work is completed on the manhole, the sewer is reconnected.
- The bypass piping is flushed with clean water and disassembled.


