WPS were contracted to install approx 30m of 180mm gravity sewer at a site in Perth.

The pipe had to be laid between an existing building and sheet piling that had been installed as part of a flood alleviation programme.
The gravity pipe had to be laid at 2.4m deep within a space of about 1.8m width which was available between the wall and the sheet piling.

Due to the space restrictions, opencut method was out of the question.

Ground conditions were sandy gravel under a layer of clay.

It was decided to drill this from the surface with the depths marked up in advance by a setting out engineer showing the depths that we had to achieve to make sure that the run on the pipe was correct.

The pipe was drilled and pulled back in a day to the satisfaction of the client with WPS butt fusing the pipe and internally debeading it prior to install.