Goole swing bridge, opened by the North Eastern Railway in 1869, carries the double track Doncaster-Hull route over the River Ouse, just to the east of Goole. It is one of largest and oldest surviving railway swing bridges in the country and has been Grade II* listed by Historic England since 1987.
It has five fixed spans and one central swing span providing two 100’ wide openings for vessels. Each span comprises three hogback wrought iron plate girders supported on cast iron cylinder piers up to 90-feet in depth to their foundations. The swing span girders are 251’ in length and turn using the original 1868 hydraulic machinery on a 30-feet diameter race of 363’ diameter rollers enclosed within a 50’ diameter pier.
Renovation
An extensive programme of renovations to this historic structure was commenced in January 2023 and was recently completed.
This major investment was needed because the deterioration of the drive, jack, and locking mechanisms of the bridge meant that it could only be swung with attendance of Network Rail’s maintenance team to manually operate the jacking. This had the effect of causing delays to passengers and also to river vessels which have precedence over rail traffic. In addition, the second, back-up drive engine had been out of action for 20 years, adding to the risks of operation. Any major failure of its mechanical elements would have resulted in the closure of the Doncaster-Hull route.
HPBW Consulting Engineers was appointed by Network Rail to carry out specialist inspection of the structure using diving and roped access. Following this it was responsible for the design of structural repairs in the central pier, the design of support for the new shore-based equipment, and for various ancillary civils items to support the M&E works.
A renovation contract was awarded to Amco Giffen to renew the operating plant, including the hydraulic turning and jacking systems, control system, electricity supply, and navigation lights.
The original plan for these works was to completely replace the operating machinery with modern equipment. However, the bridge’s listed status meant that, wherever possible, the original structure and machinery should be refurbished and not replaced.
The bridge’s location made access difficult for deliveries and so all the large components were delivered by river, from Goole docks, and unloaded by floating equipment.
The works
Major works began in June 2023 with a four-week blockade to renew the jacking systems, control system, electricity supply, and navigation lights. Works to remove, refurbish, and re-commission were undertaken following completion of these elements.
New pedestrian walkways were installed along the pier protection fendering, providing better access to cable trays for navigation lighting around the fenders, and to the bridge turning equipment. Normally, access to the turning engines and gears is down a ladder from track level, but for the renovation works two of the curved side panels to the top of the pier were temporarily removed to give greatly improved access to the crowded interior.
The operation of the bridge is controlled from the original signal cabin on the top of the bridge. It is almost all original and one of Network Rail’s oldest operational signal cabins.
The signalling interface, jacking, and slewing, are controlled via a lever frame, a pedal, and a slewing lever/handle. In line with its listed status, the existing levers have been retained but are now connected by electronic relay to a new control Programmable Logic Controller (PLC) system, rather than the existing mechanical connections. During a planned four-week blockade, RT Infrastructure Solutions installed a new circuit control lever, a new ‘free’ indication lamp within the signal box and new push button and circuit controller detection.
The bridge is turned through a gearing system by a duplicated pair of 130-year-old three-cylinder hydraulic motors. The circular pier contains a hydraulic accumulator that had provided power to the turning engines, originally charged by 12hp (8.9 kW) steam engines. The original accumulator remains in the pier top but is now redundant. A hydraulic scissor lift mechanism at each end of the swing span acts as bearings and locks the span to the approach piers when closed.
To replace the accumulator, a new hydraulic power unit was manufactured by Ipswich Hydraulics and delivered to Goole docks. This was then transported to site by barge and unloaded on the southern shore by floating a crane onto a new steel supporting structure above flood level.
The two turning engines date from the mid-Victorian period, when the standardisation of components was not common. Within these three-cylindered hydraulic engines, the pistons were not at 120-degree separation and so ran slightly erratically with a variable hydraulic flow rate required to match the varying demands of the cycle. The aim of the project was for the control of the engines to be smoothed to reduce backlash and sudden loading.
The existing accumulator on the bridge had provided a large volume at constant pressure – its modern pump replacement had to maintain flow against the variable requirement.
Measurement of hydraulic pressure revealed the peaks in the engines’ cycle and the new control equipment manages the hydraulic flow rate to match these varying demands. In addition, the engines now operate slowly, at 18rpm, with slow accelaration/deceleration to reduce strain on the gears.
Slow and steady
The refurbished bridge now opens and closes in three minutes. This is more slowly than before, but it is much more controllable and simplifies the correct positioning of the bridge over the piers. This will improve mechanism reliability, as before, forward and reverse movements had been required to joggle the bridge into position.
The gears connecting the engines to the turning ring were large and had been installed before the superstructure was erected. As a result, they could not be removed for overhaul. Some 150 years of wear had resulted in considerable backlash in the gears although non-destructive testing revealed that there were no cracks or casting defects.
The bridge’s Grade II* listing meant that every element of the structure should be refurbished and retained, with the replacement or alteration of individual components only carried out with prior agreement of Historic England.
Each engine was stripped for examination and refurbishment. Reverse engineering was required to fully understand their operation and design. When an engine stopped, the outlet was subject to full hydraulic working pressure. A solution was agreed with Historic England to raise the valves to insert a new pressure relief pipe below.
No two items were dimensionally the same, and each thread was also different. Victorian fitters constructed each engine individually, making items as required. Historical leakages between castings had not been reduced by applied sealants. The solution agreed with Historic England was to machine the contact faces and to insert double O-rings sealing plates between these. Small accumulators were inserted at each cylinder to help reduce pressure spikes, which were exaggerated by the use of modern seals, better containing system pressure. These were inserted into original bleed points so are fully reversible changes to the structure.
Engine 2 had been disused for two decades. It was the first to be refurbished and, after 28 days’ proving, was recommissioned in September 2024. Following this, Engine 1 was removed and overhauled and is currently undergoing the recommissioning process.
The bridge end support jacks were operated by a scissor supporting mechanism. Historical working had made this lift asymmetrical, making remote alignment impossible. This was one of the factors that had led to manual jacking for each swing operation.
The replacement of the bridge end jacking system was completed within the four-week blockade, with the scissor jacking mechanisms replaced by four individually controlled jacks at each end of the bridge which allow smooth, consistent lifting of the bridge ends to allow removal of the rest blocks.
The intention had been to remove the historical control equipment from the signal cabin and replace this with a push button control system. However, the Grade II* listing made this impossible and a hybrid control system has been created that retains the original jacking, slewing, and signalling levers which are connected by electronic relays to the electronic control system. The bridge operators have been trained in the operation of the new PLC system. This requires new skills but, after a learning curve, the control is now routine.
The bridge had a generator at the centre. This was difficult to access for maintenance and fuelling. The project included the installation of a shore-based generator with new directionally drilled under-river ducts to take power to the centre and to the east end jetty.
Good as new
As a structure across a navigable river, it carries navigation lighting on the span and on the west and east jetties. The project included for the replacement of these as well as the access walkway lighting on the bridge.
The various works carried out to the bridge have improved its opening and control mechanisms and have prepared it for the next phase of its long life.
James Wright, senior portfolio manager at Network Rail, commented: “This bridge has reliably served passengers travelling between Doncaster and Hull for over 150 years and is rightly considered one of the finest swing bridges in Britain, so I’m incredibly excited to have seen the asset benefit from much needed upgrades.”
Image credit: Network Rail / Bob Wright