Sep 23 – Norfolk bridge awaits its fate after “harmful” infilling

HRE GROUP PRESS RELEASE: Monday 25th Sep 2023

Bridge at Congham Before
▲A view of the bridge prior to National Highways carrying out its infill scheme. (Credit: Richard Humphrey)
Bridge at Congham Now Aerial
▲An aerial view showing the bridge and route of the old railway to its north-east. (Credit: The HRE Group)

National Highways has “misrepresented” evidence about a historic railway bridge in Norfolk, according to campaigners, as a council planning committee prepares to determine its future.

St Andrew’s Lane bridge at Congham, Norfolk was the only surviving example of a structure built entirely using a modular concrete system developed by the eminent civil engineer William Marriott, although two partial examples still stand elsewhere in the county.

In October 2019, consultants acting for the state-owned roads company informed planning officers that the structure’s ‘edge girders’ – holding up the parapets – only had a capacity of 7.5 tonnes and infilling would therefore take place “to prevent the further decline of the structure and to maintain future vehicular movements along the carriageway”. But they didn’t mention that the girders supporting the road had been assessed as having a 40-tonne capacity.

St Andrew’s Lane is narrow, with overhanging trees and a bend at the bridge’s west end. Traffic levels are light, although it is used by agricultural vehicles.

National Highways has persistently claimed that the bridge was in “very poor” condition as a result of cracks at the ends of its east abutment and the localised loss of concrete encasement to its girders. However, a 2019 inspection report – released by the consultant – rated 14 of the bridge’s 15 structural elements as “Fair”, with just one in “Poor” condition.

The bridge was infilled in spring 2021, 17 months after the Borough Council of King’s Lynn & West Norfolk was told that the project would be carried out under permitted development rights intended for immediate, temporary works in emergency situations. To comply with its obligations, National Highways should have asked the council for written consent if it wanted to keep the infill longer than 12 months. Its failure to do so resulted in the scheme becoming unauthorised and the council’s request for retrospective planning permission to be sought.

Costing £127K, the infilling work took place between 22 March 2021 and 30 April 2021, and is estimated to have involved the transportation and installation of more than a thousand tonnes of stone and concrete.

Graeme Bickerdike, a member of The HRE Group of engineers, heritage campaigners and greenway developers, said: “The risks presented by this bridge – which National Highways has misrepresented – could have been managed through repairs and the installation of crash barriers to protect the parapets, following dialogue with the local highway authority. Instead, the company’s response was characteristically disproportionate.

“It continues to downplay the bridge’s historic importance as an early modular concrete structure and no ecological evidence was sought regarding the possible transitory use of the bridge by wildlife for migration or foraging. There was no consultation with Congham Parish Council – a mistake which National Highways has since apologised for.

“As we transition to greener forms of transport, viable structures such as St Andrew’s Lane bridge should be recognised and protected for potential repurposing as part of new sustainable transport routes. Managing these assets as blots on a spreadsheet reflects a Seventies culture that has no place in today’s more enlightened times.”

The planning application has attracted 363 objections, whilst five people have expressed support for it, although two are thought to have done so in error.

Ben Dewfield-Oakley, Conservation Officer for SAVE Britain’s Heritage, described St Andrew’s Lane bridge as “a non-designated heritage asset of high local importance and the impact of the infilling to be substantially harmful in heritage terms. Burying both superstructure and substructure has effectively annulled any visual appreciation of the bridge, its historical significance and its contribution to the area’s landscape quality and railway heritage.

“The total infilling without planning permission is poor planning practice, reflecting widespread concern over the applicant’s unjustified and unsympathetic approach to managing and maintaining historic structures like this and elsewhere in the country.”

Paul Kefford, a former trustee of Historic Buildings and Places, one of the statutory national amenity societies, urged the planning authority to “reject this application as being unsympathetic to local character and history, the built environment and landscape setting.

He said that National Highways should be encouraged to “bring forward plans setting out a positive strategy for the conservation and enjoyment of the historic environment, including this bridge, a heritage asset at risk through neglect and decay and in this case the Government body becoming an ‘other threat’.”

The council officer’s report into the retrospective planning application has recommended its refusal due to conflicts with council policies relating to heritage and landscape, and similar provisions within the National Planning Policy Framework.

The application is due to be determined by the Borough Council of King’s Lynn & West Norfolk’s planning committee at a meeting on 2 October.