Have a project that requires adding a manhole to an existing line? Traditionally this would require a formed in place manhole, or bricking it. While those options work, with our unpredictable weather and soil conditions, they can turn into a headache. Our solution is to build a manhole that slips down over the existing line.
Just carefully excavate around the existing line and prepare the soil, and place this manhole over the pipe. You can then pour in the base and form the flow channel to join your new line to the existing one. The last step is cutting away the existing pipe as necessary to facilitate the new flow, minimizing mess and service interruption.