Belvedere Track Drainage Installation

THE CUSTOMER
Pro Rail Services Ltd. is a Railway civil engineering contractor who execute maintenance contracts on Network Rail infrastructure. This project took place on Network Rail’s South East Route of the network.

THE CHALLENGE
Rail services through Belvedere Railway Station in the London Borough of Bexley were being compromised by poor track drainage causing wet beds. This resulted in temporary speed restrictions having to be put in place, adversely affected the reliability of passenger services.

The main cause of the problem was the lack of track drainable assets at the station.

THE SOLUTION
Pro Rail Services Ltd. was commissioned to install 170 metres of new track drainage. This was made up of semi-perforated high density polyethylene (HDPE) pipe (internal diameter: 225mm), linked via 6 glassreinforced plastic (GRP) catchpits.

Initially, the track drainage was designed to outfall into an existing culvert. However, it was identified that project costs could be reduced by moving the outfall to a ditch nearer to the station. The change was approved 10 days before the implementation date. However, Pro Rail Services Ltd. still had time to introduce an innovation. In what is thought to be a first for track drainage, the pipe outfall was established with a GRP headwall, instead of a concrete one.

GRP headwall – key benefits:
• Improved safety, through a reduction in manual handling risks. The GRP headwall weighed just 50kg
• Faster installation, due to the reduction in weight, more compact design and no need for specialist lifting equipment
• Reduced cost, due to no need for hire of lifting equipment and easier transportation.

THE IMPLEMENTATION
A railway drainage systems manufacturer, Aqua, was commissioned to design and supply the GRP headwall.

The track drainage system was installed during a 52-hour possession between 7-10 April 2017. Work was carried out in 12-hour shifts, with 50 track drainage personnel working on each shift.

4x road-rail vehicles (RRVs: 2x PC118, 2x PC138), 2x 5-tonne excavators and 2x trailer units were used to carry materials and equipment to and from the worksite.

At one point, work had to be suspended for three hours, and all equipment and materials were demobilised and transported to a depot three miles away, to allow two tamper trains to travel through the station.

THE RESULTS
Early indications are that the wet beds that were previously identified have been removed.

A new method for creating a track drainage outfall, using a GRP headwall, has been implemented. This technique can now be used again elsewhere, generating the benefits described above.

The track drainage was installed according to the programme and on budget. The GRP headwall was installed successfully and performed in line with specification. No incidents or accidents were reported.