Initially, DrainsAid undertook Jetting and CCTV investigative works to understand the current condition of the drainage systems at a major factory in Yorkshire. After uncovering a number of faults within the system, we advised our clients that replacement actions were necessary to avoid further deterioration, which may have been expensive and difficult to resolve.
Unfortunately in this situation, excavations were a necessary requirement due to complete drainage collapse, which could not have been repaired using trenchless rehabilitation methods.
As the work was to be completed on private land, no notices were required. After traffic and pedestrian management assessments, our supervisor Greg Thomson decided only Heras Fencing, cones and barriers were necessary to segregate site traffic and personnel from our work area.
We were tasked with the excavation and replacement of a 20m slot drain, and the replacement of three sunken manhole lids outside in the factory yard.
Firstly, we began work on the replacement of the slot drain, which had collapsed in places and was full of concrete, meaning ground water could not escape, which may have lead to localised flooding. After removing the surrounding concrete, our fully trained operatives broke out the existing drain, before installing a new Safeticurb DBM slot drain. We ensured there was enough fall to allow any groundwater to travel to the outfall pipe, which runs to a nearby manhole.
Using a Class 1 mortar mix, we reinstated the surrounding area. Due to the shallow nature of the drain, excavations remained minimal throughout.
Replacement of the three sunken manholes was undertaken in a similar manner, by breaking out the lids and surrounding concrete, before building the manhole back up to road surface level. We drilled holes to install a rebar to tie the lid into the existing concrete floor, before bedding the lid.
For each replacement, we surrounded the concrete mix with 25mm of compressible joint filler topped with 25mm x 25mm mastic sealant. These were then covered with road plates and left overnight to cure. All works were completed within the timescale our clients required.
