A challenging £6m high profile project to refurbish Scarborough Rail Bridge over the River Ouse in York has been completed safely, within budget and ahead of programme – despite many constraints.
These included restricted access on a historic city centre site in a residential area with narrow streets, and close to important rail lines, in a high profile location under constant close scrutiny from the client and the public.
The project was needed because the 140-year-old bridge’s timber deck, approximately 10 metres high above the river, was badly degraded and the structure was life-expired and therefore needed replacement.
The bridge carries the York to Scarborough line and an adjacent foot and cycle route over the river between Leeman Road and Clifton.
The scheme has delivered the most significant improvements since the bridge was built in 1875 and will mean that the bridge is fit for another 120 years’ service.
In addition, the bridge won’t need maintenance for many years and has improved track drainage, whilst the footbridge attached alongside has also been refurbished and repaired.
The improvements also mean that the bridge is capable of carrying heavy steam services, such as the Flying Scotsman.
The works included the removal and replacement of the approximately 48-metre long two span bridge deck, together with the track, plus structural repairs including works to the bridge’s attached footbridge and the construction of a temporary access platform on the other opposite side of the bridge to provide access for construction site staff.
The project was carried out for Network Rail by main contractors Story Contracting.
The first phase of work involved setting up the site compound at nearby Marygate Car Park, followed by approximately two months spent forming a platform for a 500 tonne Demag CC 2500-1, crawler crane, as the car park surface was unsuitable for taking this amount of weight. These works involved the installation of 200 piles with concrete caps to form runners for the crane tracks.
The bridge decks journeyed to site jacked up on their trailers, allowing them to sit further forward than would otherwise be the case.
The new weathering steel decks, manufactured in Chepstow by Mabey Bridge, are U-shaped in section. Whilst not aesthetically pleasing, the decks will demand no substantive maintenance for 60 years. In any case, they are screened by newly-fabricated latticework on the west side of the bridge – emulating the original – and the existing footbridge to the east.
As a result of their 24-metre length, the decks had to be reversed down Marygate for 300 metres in order to take the right-hand turn. Areas of the footpaths on Marygate were matted out for these manoeuvres with some lighting columns removed.
A logistics phase followed, comprising all the planning required in readiness for installation of the bridge deck, including co-ordinating delivery of all the materials required.
The crane, which had an 84-metre boom, then had to be assembled at Marygate Car Park to carry out the heavy lifting required, including moving the new bridge spans into place. The crane parts arrived in approximately 18 wagons and took three days to assemble. The crane was around 85 metres high – about 15 metres higher that York Minster – and up to 400 tonnes of counter weights were used during its operation.
A ‘blockade’ lasting just over nine days followed, when the engineering work involved in removing and replacing the original track and bridge deck prevented trains using the bridge between February 14 and February 23 2015, with coaches replacing First Trans-Pennine Express trains between York and Seamer and river traffic also being stopped.
Six lifts were required to remove the original bridge. The new bridge was then installed, complete with four new bridge decks, in a dramatic and high profile operation.
To ensure optimum efficiency, the sequencing of lifts for the bridge removal and installation was planned methodically by the Story team to minimise the number of changes in the crane’s position and loading.
Steelwork repairs were carried out to the original bridge structure and the footbridge, and the new track, measuring 250m was installed, together with 800 tonnes of ballast, with a tandem lift required to install the switch panel.
Completion of the works involved dismantling the crane and disposal of the old bridge sections, as well as the removal of many of the piles and concrete pads used to form the crane tracks – although one of the concrete pads and a number of piles were left in situ to be used in a future project to renew the footbridge, which will be carried out in a few years.
As part of the work, it was necessary to remove some trees and vegetation from the railway embankment immediately north east of the bridge. These are being replaced with a replanting scheme.
A full ecological study was carried out and Story Contracting worked closely with the Canal and Rivers Trust, Natural England and Environment Agency, securing the necessary permissions. This was because the River Ouse was closed to river traffic at certain times while the works were undertaken.
“The Scarborough Bridge had given good service for 140 years was due for refurbishment. Many parts of the bridge will not now need any further work for decades,” said Phil Verster, route managing director, of Network Rail.
Network Rail worked closely with the City of York Council and First TransPennine Express throughout the project to minimise the impact of the work on both local residents and the travelling public.
Nick Hill, project manager at Story Contracting and lead Project Manager for the Scarborough Rail Bridge scheme said: “This was a complex project with the location of the bridge being a particular challenge.
“We had site compounds on both sides of the bridge – the one on Marygate Car Park adjoining the railways western boundary, and another adjacent to York Station at the end of the platform, which was where all our plant, machines and materials were stored. We had direct access onto the railway line from this point.
“Because the footbridge was classified as a separate structure, it had to remain in place throughout the project. The footbridge itself also required repair, so whilst this was being carried out, contractors were unable to use it as an access footpath. The perfect solution was to construct a temporary scaffold footbridge on the opposite side to the original footbridge.
“When the bridge spans, weighing approximately 61 tonnes each, were craned into place from their location at Marygate Car Park, one of the biggest challenges for us was the logistics of managing the area and establishing a programme which avoided any clashes of movement, making sure that everyone in that area remained safe and we were able get the job done as efficiently as possible.
“Surprisingly, the actual process of moving the new bridge decks was one of the most relaxed elements of the project, because we had put so much work into planning the operation beforehand. Everything went just about to programme and as planned. Everyone knew their job and simply got on with it.
“In fact a considerable amount of work was needed just to get the spans to the car park on low loaders. We brought the spans in one at a time over two consecutive nights, which included liaising with local residents to make sure they did not park in certain locations along the route we were using whilst this operation took place. The residents were very co-operative and were more than happy to move their cars.
“Other works included the infilling of several voids under each of the abutments at both ends of the bridge. Network Rail wanted to prevent water ingress and avoid any possible resulting damage to the structure, so we used a void filler to remediate this.
“A significant challenge was the complex planning required throughout the scheme – largely due to the project’s location with nearby residents and businesses. As a result, this was the highest profile scheme I have ever worked on.
“Also, during the ‘blockade’ when we were installing the new bridge spans, we were under media scrutiny, including from newspapers, TV and radio, as well as through videos of the project being posted on the internet.
“Site safety was key at all times, and fortunately all staff bought into this really well and we had a very good safety culture throughout the project. We even had safety boats on standby in the River Ouse, as an extra layer of safety for our staff, although fortunately, the boats were not needed.
“We had a particularly good working relationship with Network Rail – in fact we worked together in the same office and there was extremely good liaison and co-operation throughout.
“This was the only way to carry out the project successfully, as it would not have been possible to do everything via email or telephone – and this was vital to the success of the scheme. Another positive element was that everyone on the site team together with all the sub-contractors involved, had the right attitude and really wanted the project to succeed.
“We were also fortunate with the weather, which was clear and dry with little wind – and the river level was very low – so conditions could not have been any more favourable, which is something we cannot often say in this country.”
An unusual element of the scheme is that Network Rail constructed a Lego model of the bridge which was remarkably detailed – including the track layout and little orange men with chainsaws – which could be deconstructed and rebuilt to follow the lifting sequence. Sitting as a centrepiece in the site conference room, it proved more useful than a PowerPoint presentation when explaining the challenges to visitors and stakeholders.
TICS Rail Signalling carried out signalling works testing to facilitate the bridge replacement. This involved temporary alteration of track circuits and false feeding points essential to allow York Station to continue its normal operations.
The team also verified the existing controls of the station to ensure there was no passenger disruption. Following the bridge replacement TICS Rail Signalling completed the testing of the new point equipment and track circuits by removing temporary works to allow all lines to return to normal working on time.
Celebrating 25 years in the general construction industry, and with over 10 years’ experience of permanent way and rail related building and civil engineering projects, Story Contracting has grown into a highly respected and well known company offering national coverage.
The company is ideally located with bases in Cumbria, West Yorkshire, South Lanarkshire and Midlothian which offers ready access to the West Coast Mainline and M6 transport routes, as well as providing an ideal base for coverage of the North of England, Scotland and the East Coast areas and down to the Midlands.
Network Rail are steadily improving the rail network, providing faster, more frequent and more reliable journeys between Britain’s towns and cities. This is bringing people and businesses closer together, making Britain more competitive and a better place to do business
This brings wider benefits to the economy; rail investment stimulates private sector growth, and Network Rail are investing in their workforce and introducing new technologies.
When Network Rail took over the railway network in October 2002, they inherited an infrastructure that had been starved of investment for many years. Now the company’s approximately 35,000 staff are working hard day and night to improve every aspect of the railway.
Enormous progress has already been made and the railway is already safer, more reliable and more efficient than ever.
Wood Group Industrial Services Limited erected the scaffolding on site for the Scarborough Bridge project and were on site for three months. The firm delivers a number of scaffolding, industrial painting, marine and offshore painting, construction and asbestos services to a range of clients.
Michael Steinmetz of Wood Group Industrial Services Limited commented:
“It was important to be involved with a prestigious project like this as it increased the reputation of the company resulting in new orders going forward.”