Network Rail has lost its battle with a local council to demolish a grade II listed bridge which could have serious knock-on effects for the speed of new electrified trains on the Great Western Main Line.
The Vale of White Horse District Council voted against the demolition of the three arch, masonry arch road bridge, which is too low and does not give the required clearance between the new catenary wires and the trains.
New overhead lines have been installed under the bridge, but speed restrictions will now be imposed when the lines are electrified in December this year, due to the steeper gradient of the cables and the risk of the train’s pantograph hitting the bridge.
Plans are for the electrified trains to reach a speed of around 153km/h between Didcot and the bridge with a maximum speed of 200km/h. However, with speed restrictions this will reduce to 95km/h.
The council, in objecting to the motion, said that the increased journey times of between 4.4s and 9.1s due to running in diesel mode under the bridge were within the “noise” of timetable scheduling and would have no significant effect.
However, Network Rail senior sponsor for Western Route Nick Preston told New Civil Engineer that the delay would be 1 minute 30s per train between Didcot and Wantage Road.
It also said it had concerns over the impact of closing the bridge for a minimum of 10 months on local businesses and homes.
Network Rail said lowering of the track to give the required clearance to operate at full speed was not an acceptable solution.
In the planning application it said that to maintain an acceptable gradient for the track, approximately 800m of track either side of the bridge would have to be renewed to lower it by the required 770mm.
This would put the new lowered track into a “zone 1” flood area, the highest level of flooding, requiring separate permits from the Environment Agency. It would also mean a nearby level crossing giving road access to homes and businesses would have to be closed.
A response in the document from “neighbour 1”, who “strongly opposes” the demolition of the bridge said the new trains were designed to go through flood water and this should not be seen as a barrier to lowering the track.
In addition to the potential flooding issue Network Rail said to allow it to form a new track bed, 1500mm would have to be excavated. It said an excavation of this depth would likely destabilise the bridge’s foundations and require significant earth retaining structures to be installed around it.
Historic England, Environment Agency or the conservation officer for Vale all said they felt the benefit of electrification outweighed and the loss of a heritage asset.
A spokesperson for Vale of White Horse District Council said: “At the meeting, the Planning Committee heard from a number of interested parties, including Steventon Parish Council and Network Rail.
“Following consideration of all the information presented Committee determined that there is no convincing justification for demolishing the bridge. Steventon Overbridge is a Grade II Listed structure and removing it would be harmful to the local area and contrary to a number of local and national planning policies.”
Network Rail said it would be launching an appeal against the decision.
“We are disappointed that the Vale of White Horse District Council rejected the planning application for the demolition and replacement of the railway bridge at Steventon,” said a Network Rail spokesperson. “We are currently considering our options, and looking to submit an appeal”.
In 2016 Elevarch, a subsidiary of contractor Freyssinet, carried out a full scale test to lift a 160-year-old masonry arch bridge 900mm for the first time, offering an alternative method of providing additional clearance for rail electrification works.
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