CARLOWSE campaigners have lodged an objection with Historic Scotland over planned work to their historic bridge.

But the heritage watchdog doesn’t believe scheduled concrete strengthening is breaching the rules.

Scottish Borders Council are currently preparing the site in rural Tweedsmuir ahead of repairs to the B-listed structure.

But an independent expert, who undertook a week-long survey of the 230-year-old bridge, believes the planned strengthening is outwith guidelines. And her advice had led to a local community group - Tweedsmuir Bridge Advisory Group (TBAG) - complaining to both Historic Scotland the local authority’s Heritage Officer.

Adrienn Tomor from the West of England University said: “Masonry arch bridges can be strengthened with a selection of suitable methods, such as concrete saddle, relieving slabs and retro-reinforcement depending on the nature of weakness in the structures.

“Filling masonry arch bridges with concrete is not listed as an appropriate method in any guideline. The basic principle for all works undertaken on masonry arch bridges is that wherever possible, repairs must be sympathetic to the structure, not alter its working mode and use materials compatible with those already existing.

“The proposed works to fill the Carlowse Bridge with concrete will clearly change the nature of the bridge and it will no longer function as a masonry arch bridge.

“Additionally, any work on a historic structure will require specialist advice to ensure that the historical value of the bridge is not diminished forever.” A row over the best solution for the historic bridge has been rumbling for several years.

TBAG wanted a permanent second crossing to accommodate heavy logging vehicles with a new weight restriction imposed on the current arched structure.

But members of the council’s ruling executive voted in favour of their officers’ cheaper option - although the repair bill has since escalated by almost £160,000 to £569,000.

Paul Greaves from TBAG said: “We feel the Scottish Borders Council work will wreck the historical significance of a B listed structure and contravene Department of Transport guidelines.

“What is planned is not a recognised technique and should be approved by Scottish Ministers as per Historic Scotland guidelines - and not simply rubber stamped by the council’s own planning department.

“We have protested to Historic Scotland about this and also raised it with the Heritage Officer at the council. We’re also considering making the Scottish Government aware of what is going on.” Scottish Borders Council has defended the planned bridge works.

And stated that it won’t be holding up its scheduled start date.

A spokesperson for the local authority said: “A conservation specialist within our Built and Natural Heritage team was consulted about the proposed works at Carlowse Bridge.

“It was considered that the repair works would not affect the character or appearance of the structure and as a result would not require a formal Listed Building Consent application, as noted in Historic Scotland’s Scottish Historic Environment Policy.

“This approach has been taken on a number of occasions previously in respect of road bridges.

“The Built and Natural Heritage team will continue to liaise with the project team as work progresses to ensure that the character of the bridge is retained.

“The use of concrete as infill can enhance the distribution of load throughout the structure, and this process has been carried out previously on the bridge network. Each bridge must be assessed on its unique merits and an appropriate design solution drawn up.

“The repair works are advancing well, with the temporary bridge due to be installed at the start of next month. The Council will continue to communicate with the local community.” Historic Scotland don’t believe Scottish Borders Council are breaching any regulations.

A spokesman said: “We have been in contact with the Tweedsmuir Bridge Advisory Group concerning the planned repairs to the 18th century, category B listed structure.

“In the case of the bridge, it was for the council - as the planning authority - to determine whether Listed Building Consent was required, which is only necessary for works affecting the character or appearance of a listed building or structure.

“Most works of repair do not require consent and, in this case, the council determined that it was not required, so Historic Scotland were not consulted.”