General update on Network Rail swing bridges
The Broads Authority has developed a good working relationship with Network Rail and they share our frustrations with the challenges that non-operation of bridges causes to navigation of the waterways.
Whilst it has been possible to make some improvements, the fundamental problem of an old infrastructure remains. The huge investment required to replace this infrastructure is not available, so Network Rail are doing what they can to make improvements to what we have.
There is a dedicated Anglia Maintenance group including signallers, capital repairs, legal and rail maintenance who are able to respond to bridge issues in the Broads as a priority. Whilst access to this group is not public the Broads Authority is able to inform them of problems and ask for assistance.
The bridges that experience problems are old Victorian structures and whilst the technology used when they were built was considered state of the art at the time, they were not designed to deal with modern challenges, so the bridges do fail. Network Rail have agreed that when this happens these bridges get priority. There is a genuine willingness to address this issue in the Broads despite the fact that there are limited resources to look after a massive rail network and many structures which all have issues.
So, what is Network Rail doing to keep the swing bridges in operation?
In summer, Reedham and Somerleyton have the last rails on the bridge painted white to help reflect heat and prevent expansion and kinks in the rails. But this cannot protect against the effects of expansion of the entire bridge structure when the temperature is above 26 degrees. To counter this, Network Rail has invested in shorter rails (these shorter rails are locally known as ‘summer rails’ but are actually fitted all-year round) and a new sensor system to Somerleyton and Reedham bridges has been fitted. These have upgraded the capability to deal with extreme temperatures.
The bridges have also been fitted with a water sprinkling system, in an attempt to cool the structures, but when the temperatures are in the high 20’s the structure expansion is too great for the water system and the system becomes ineffective. Spraying river water onto a cast iron structure also leads to other issues like rust and corrosion of bearings and joints.
Network Rail also has plans to renew some of the operating components on the three swing bridges, Reedham, Somerleyton and Oulton Broad, as part of its Railway Upgrade Plan. These are scheduled to be completed by spring 2024.
You can find out more on this by visiting Network Rail's website at: https://www.networkrail.co.uk/running-the-railway/our-routes/anglia/swing-bridge-renewals/
Thursday 13 August 2020