Drains Limited were called out to Highgate School in the North London Borough of Islington to unblock a drain in the school’s changing rooms, sited out on the school playing fields.
Highgate School contacted us after noticing a blockage in the foul drain exiting the changing rooms. As a school there is of course a duty of care issue in needing to use DBS checked and approved drainage contractors, which Drains Limited were able to satisfy. Our drain engineers were soon out to the school to investigate the drainage problem and provide a solution.
Our drain engineers carried out a CCTV drain survey to quickly locate and identify the cause of the blocked drain. An inspection of the CCTV footage revealed the location of the blockage in the foul drain pipe. The blocked drain had been caused by the collapse of a section of the pitch fibre pipework, which is renowned for these kind of issues. The pitch fibre pipe in this case was deformed with internal blistering along its entire length. We also identified a broken clay channel in the base of the tumbler chamber.
To complete the drainage pipework repairs our drain engineers used a digger to excavate a 60 meter section of the pitch fibre pipework between the changing rooms and the last manhole before the main sewer system. Before removing the collapsed pipework our drain engineers tested the construction of the pipework and it was found to be an asbestos containing material. As a dangerous substance asbestos must be handled with due care and disposed of properly. As such we called-in one of our approved specialist contractors to dispose of the pitch fibre pipework.
Once the damaged pipework was removed our drain engineers set-about installing the replacement drainage pipework. As part of installing the new pipework our lead drain engineer decided to increase the gradient of the pipework in order to improve the flow of waste out of the building and eliminate the prospect of future drainage blockages. The pipe was connected and entered the man hole at a lower level by the internal tumbler and the broken clay channel in the base of the chamber was replaced.
Our drain engineers then performed a test of the new installation to ensure that it was sealed and performing as expected before back-filling and compacting the trench.
The new pipework was bedded on and surrounded with 10mm pea shingle for added protection prior to back-filling.
As you can see from the photos, our team of skilled drain engineers were able to lay the new drainage pipework and return the ground in school playing field to a safe environment for the children to be able to resume their sports activities.