Works carried out during a long-running project to upgrade the M27 in Hampshire to smart motorway status prompted an emergency callout to Selwood’s pumping solutions specialists.

MTS Cleansing Services Ltd has a long-standing and highly-collaborative relationship with Selwood, having partnered closely to deliver solutions for several projects on behalf of Southern Water.

MTS was dealing with the fallout from a breach of a sewer on a site just off Allington Lane, Eastleigh, near Southampton, as a result of the motorway works. A piling rig had damaged the sewer to the extent that it was impossible to repair.

The challenge

The damaged sewer needed to be overpumped so that a replacement could be installed. This required the use of a large diameter pipe capable of flows of up to 120 litres a second through a drinking water site and under the motorway.

The installation needed to be carried out quickly but carefully to avoid the risk of sewage leaking into drinking water supplies. An additional challenge was restricted access along the discharge route, meaning pipework there needed to be positioned and installed by hand.

The solution

Selwood’s solutions teams worked closely in partnership with MTS manager Matt Webster to devise a solution. The team decided to use 250mm HDPE electrofusion welded pipe for the discharge. This 10-inch pipe weighed in at 60kg, meaning lengths could be carried into position by hand.

The joints were then fusion-welded together on-site to eliminate the possibility of any leaks. Track matting was used to help in the fuel management of the pumps to prevent damage to the field.

The team installed two Selwood-manufactured S160eco solids handling pumps and one S200 unit. Full telemetry was provided through the SelWatch system which allows real-time remote monitoring of performance and fuel levels. A flow meter was also fitted to ensure the required flows were met.

A drain down line was fitted to allow MTS tankers to wash out the pipeline to prevent any sewage spillages when the overpump system was being removed at the end of the job. This line also served as a failsafe during the project, as it could be used to load the tankers if higher flows needed to be pumped.

The result

The customer benefited from a fast emergency response and a standalone, remotely-monitored solution that overcame the challenges of installation. The solution was fully managed by Selwood, eliminated the possibility of leaks and included a contingency to cope with higher flows if required. It was quickly and safely removed without issues once the sewer replacement was complete.