Drains Aid - Innovative

DrainsAid, the innovative drainage and sewerage division of award winning company Peter Duffy Limited, has recently completed a large scale rehabilitation project over a rail track in Huddersfield, West Yorkshire.

The project was carried out to repair a 750mm diameter sewer in Branch Street on behalf of client Yorkshire Water.

On inspection DrainsAid found that the problem was due to a corroded section of the cast iron pipe which was causing the flow to escape from the sewer onto the rail tracks below.  DrainsAid and Yorkshire Water set about preventing any irreversible damage and stop the egress of water leaking from the sewer. The project was not straightforward as DrainsAid found there were obstacles to overcome before it could be completed.

Overcoming obstacles                    

Under normal conditions this should have been a fairly straightforward project for the team but there were a few challenges that DrainsAid had to overcome to provide their solution.

DrainsAid identified that, due to the corroded condition of the host pipe, it would be unsafe to use a conventional CIPP hot cure liner as this solution is water based and may have overloaded the pipe. Instead, DrainsAid decided to use their UV lining method.

The main benefit of using a UV liner is that it is a great deal lighter than a CIPP hot cure liner. As the UV liner is inflated with air, rather than water, the curing time of the liner is greatly reduced. Time was important on this job as access to the sewer was to be made in a busy road and disruption had to be minimised. The team only had one day to complete the works, so speed was essential.

The opening of the manhole chamber was offset to the line of the damaged pipe and had limited access. As the team would not be able to reach the pipe via the chamber, they instead had to carry out a large excavation requiring a road closure to remove a 2.5m x 2.5m 0.25m thick concrete cover slab. The excavation allowed the team to have better access to install the liner.

Further to this dealing with the flow posed a problem and required over pumping of the flow 260m through a field to the nearest suitable point.

Overcoming all obstacles, the team were able to install a 6mm thick 750mm diameter UV liner. As UV lining is faster curing, the team were able to complete the liner in under 5 hours, saving considerable time when compared to a traditional hot cure liner which would have taken around 18 hours.

Fast, effective results

“Due to the initiative and excellent organisational skills of the DrainsAid team and the pre-project meetings and site visits, the planning of this job was extremely detailed and resulted in the installation on the day going to plan,” said Lining Supervisor Gerard Healy.

“The highway restrictions meant that we were only able to perform this work on a weekend and the project had to be completed within the day. This meant that there was excavation work to be completed on the downstream manhole before we could start the lining procedure,” he continued.

“This put a delay on the works and made for an extremely long shift but, as always, the team were excellent and really went the extra mile to ensure the project was successfully completed on time.”

Yorkshire Water Core Customer Solution Technician Andrew Styles said, “DrainsAid has done an excellent job using the UV lining process to resolve a complex issue. The work was carried out with speed and, due to their initiative, the solution has come out even stronger.”

The UV lining solution installed by DrainsAid was 58m in length and the outcome is that the pipework has been secured, preventing any leakage and reducing the risk of failure and the potential for flooding of the rail track and surrounding area.