While Manchester slept: photos reveal overnight gas pipe repair above busy railway

Newly released photographs show engineers working against the clock to repair a 114-year-old gas pipe above an electrified railway line in Manchester.

The complex operation by Cadent, which manages the local gas network, took place at Cornwall Street in Clayton, where a cast-iron gas main is attached to a railway bridge and runs directly above the Manchester Piccadilly to Sheffield route.

Installed in 1912, the pipeline supplies around 8,000 properties.

While the repair required specialist engineering expertise, safely reaching the pipe presented the biggest challenge.

Because the gas main sits above an electrified railway, Cadent first had to secure a tightly controlled overnight possession of the route, during which the electricity supply to the railway could be safely switched off.

Months of planning and close coordination involving Cadent, Network Rail, specialist contractors, arborists and access teams were needed to create the short window in which the repair could take place.

Once the line had been de-energised and handed over, engineers had only a matter of hours to access the pipe, complete the repair and clear the railway. This had to be achieved with enough time remaining for the line to be safely re-energised before passenger services resumed at 8.30am.

The pressure intensified when a late-running train from Glossop delayed the start of the operation. Although the possession window had been scheduled from 12.30am until 8.30am on a Sunday morning, the team could not begin work until around 2am. This reduced the available repair window to approximately five hours.

Marc Chester-Lees, Technical Specialist at Cadent and authorising engineer for the work, said: Because the pipe is positioned directly above an electrified railway, we could only carry out the repair when power to the line had been switched off. Securing that access took months of planning, and once the railway was handed over to us, every minute counted. We had one opportunity to complete the repair and safely return the route for the start of passenger services.

The pipe is situated around five metres above ground level, while nearby trees further restricted access. The presence of overhead electrical equipment meant traditional scaffolding could not be used, so the team brought in a specialist mobile elevated working platform to lift engineers safely above the tracks.

Once lifted into position, the Cadent engineers completed the repair in four hours. The work was finished and the site cleared by 6am, allowing the railway to be safely re-energised before the morning timetable began.

Engineers used an external injection technique to complete the repair, avoiding the need to add further weight to the ageing structure through encapsulation.

The successful operation means the gas network is continuing to safely supply around 8,000 properties while longer-term plans progress to divert the pipeline away from the railway corridor entirely.

Phil Hendrick, Head of Operational Delivery (North West), Cadent: This was a very challenging repair operation, delivered brilliantly. We made sure everyone was safe – our team and the public – and kept an uninterrupted supply of gas to local homes.

Cadent is the UK’s largest gas distribution, managing a network of more than 80,000 miles of pipes which distribute energy to more than 11 million homes and businesses, as well as hospitals, schools, offices and industrial sites.