National Highways could be ordered to remove over 1,000t of infill from beneath an historic bridge in Norfolk if its retrospective planning application for the work is denied. Believed to have been constructed in 1923, the St Andrew’s Lane Bridge at Cong ham, Norfolk carries an unclassified public road (St Andrew’s Lane) over the former South Lynn to Yarmouth Railway line. It was the most elaborate of six such bridges built using an innovative system of modular concrete components developed by William Marriott, engineer of the Midland & Great Northern Joint Railway. The traffic levels on the bridge are described as “light”, but it is used by some agricultural vehicles. It was infilled in 2021 for a cost of £127,000 and with an estimate of over 1,000t of stone and concrete. In January this year King’s Lynn and West Norfolk Council demanded that National Highways submit a retrospective planning application for the work. With weeks to go until the decision from the council, the HRE Group – a group of engineers, greenway developers and heritage campaigners – has called on anyone interested in railways, social history or active travel to object to the application. It has called the infilling a “destructive burial” and says that it “demonstrates just how clueless [National Highways is] when it comes to heritage”. The St Andrew’s Lane bridge is a single span square overbridged comprising seven longitudinal girders with the spaces between them infilled with concrete jack arches. Wingwalls are located in each corner which extend approximately 5.5m from the bridge parapets. The wingwalls, abutments and parapets are constructed from concrete blockwork. Jacobs carried out a series of structural assessments of the bridge in 2019 and concluded: “The edge girders are restricted to a 7.5t Gross Vehicle Weight. Furthermore, the eastern abutment is exhibiting indications of movement, resulting in numerous cracks appearing beneath the edge girders and along the abutment faces. The faces of the longitudinal girders are also showing defects with some beam exposure in some instances. The wingwall coping courses and the south west newel are demonstrating minor failure and collapse, which could be caused by the dense vegetation present on all embankments.”

However, a 2003 Assessment of The Bridge Said That.

the girders under the carriageway had a capacity of 40t. The HRE Group points out that this is absent from Jacobs’ 2019 conclusions. Major repairs were carried out on the bridge in December 2009 and February 2010, including propping being installed and the fractured area being cut out and repaired. The contractors reported that the bridge still moved when HGVs travelled over it. Following its 2019 assessment, Jacobs wrote to the council and National Highways saying: “To prevent the further decline of the structure and to maintain future vehicular movements along the carriageway, the proposal is that the bridge is subject to structural infill.” National Highways says it carried out a thorough review of the structure against factors such as safety, ecological and heritage value. It is committed to only demolishing or infilling structures where there is a significant risk to public safety and there is no realistic or practical alternative. National Highways ordered the infill as it was the most cost effective option for saving the structure and the area under the bridge was not open to the public. As the bridge is part of the Historical Railways Estate (HRE), owned by the Department for Transport and looked after by National Highways, it is deemed “Crown Property”. This allowed National Highways to order the infilling under Class Q of Town & Country Planning Order of 2015. However, under the same order, it is obligated to restore the land to its former state within 12 months or seek written permission from the council if it intends for the infill to remain for longer. National Highways did not get permission for it to remain for longer than 12 months and this has resulted in the scheme becoming unauthorized, hence the requirement of a retrospective planning application. The HRE Group is campaigning for the retrospective planning application to be denied and for National Highways to be ordered to remove the infill. HRE Group member Graeme Bicker dike said: “The bridge had defects typical of most legacy structures and presented only modest risks given the prevailing circumstances. The action taken by National Highways was characteristically disproportionate. “They infilled the structure for routine asset management purposes, but chose to exploit rights that apply to urgent, short-term interventions. The scheme was part of a programmed of more than a hundred bridge infills, with almost one-third of them being proposed under these misapplied emergency rights. Some of the structures had no meaningful defects.

“The Historical Significance of The Bridge Wasn’t Considered.

By National Highways when it decided to undertake this destructive burial. Nor did it take into account the unwelcome environmental impacts of transporting a large amount of quarried material and placing it in a rural landscape, or the structure’s potential to play a useful role as we transition to a greener future. “In its planning application, National Highways claims the infill ‘barely alters… the perception and enjoyment of the bridge’ which is now ‘preserved within the infilling for posterity’. This demonstrates just how clueless they are when it comes to heritage; they simply do not understand their responsibilities as custodians of legacy assets.” National Highways head of the Historical Railways Estate programmed Hélène Rossiter, said: “Cong ham Road Bridge was infilled in February 2021 because we viewed it as a public safety risk. When we took over management of the bridge it was in a very poor condition and had started moving. Previous repairs conducted by our predecessor were failing as a result of this movement, suggesting that further repair would not resolve the issues. “We consulted with the local planning and highway authorities beforehand, and they confirmed they had no objection to the works and that the scheme didn’t impact any of their active travel plans. “We have been in touch with the King’s Lynn and West Norfolk Borough Council, the local planning authority for the bridge, to ensure that there are no plans for active travel or heritage railway that would be prevented by infilling the bridge. We’re in regular dialogue and welcome scrutiny. “A retrospective planning application to retain the infill has been submitted and we can provide further comment once that process concludes.”This battle is a continuation of one between National Highways, the HRE Group and Eden District Council over the infilling of the Great Musgrave bridge in Cambria. The 161-year-old masonry arch bridge was also infilled in 2021, and when images of the work appeared online NCE readers described it as “disgraceful vandalism” and expressed shame at being an engineer. A report on the bridge’s health said that it was not weak or at risk of collapse, presenting no real threat to safety nor needing any form of support. National Highways submitted retrospective planning application for the infilling of the Great Musgrave Bridge to Eden District Council, but this was denied in October 2022. The roads operator was given 12 months to remove the infill, with a deadline of 11 October 2023. In 2021, the Great Musgrave infill removal job was costed at between £80,000 and £90,000, while the estimated cost of bringing the route under structure back into use for active travel was between £316,000 and £431,000. This is a saga that could continue, as the infilling of the Rugate Road bridge in Newton Kym, North Yorkshire is now under scrutiny. In December last year, Selby District Council confirmed that it would order National Highways to submit a retrospective planning application for the work, and it has now been revealed that it plans to do so by the end of June.