On Monday, 12 August Network Rail reopened the mile-long Blackheath Tunnel, which had been closed for essential upgrade works since Saturday, 1 June.

The work was necessary as the tunnel suffers from numerous leaks which in turn cause damage to track and equipment inside the tunnel.

Faults related to damage in the tunnel frequently led to delays and speed restrictions for the Southeastern trains that pass through the tunnel on their way between Dartford and Cannon Street via Charlton, Blackheath and Lewisham.

The project required use of a specialist industrial vacuum which removed soot from the tunnel lining.

Bricks inside the tunnel were also replaced, while several surveys were carried out in order to prepare for further upgrade works next summer.

During the 10-week engineering work period, services that usually ran through the tunnel were diverted via Greenwich, and customers were advised to use TfL bus services for certain journeys.

The tunnel was built in 1849, and the summer repair works were carried out by Network Rail in partnership with one of its delivery partners, the Southern Integrated Delivery (SID).

It is hoped that Southeastern passengers on the line will now benefit from improved reliability.

The reopening means that Southeastern is now able to operate its full new timetable, which came into force on Sunday, 2 June.

We’re grateful to everyone’s patience while we’ve undertaken the work within Blackheath Tunnel over the last 10 weeks.

We’re in the process of renewing everything within the tunnel, which includes replacing the track. That means we’ll need to return to Blackheath to complete this work over the next few years so that we can keep this Victorian-era structure in the best possible condition. We will now assess the further repair work needed for next year and will keep passengers and stakeholders informed on next steps.

David Davidson, Network Rail’s Route Director for Kent