Historic bridge damaged by a tractor in Derbyshire
Repairing historic humpback bridges over canals after they are hit by cars is costing British Waterways £2.5m a year, it has been revealed.
It says the money for repairs is being diverted away from maintenance of British Waterway's 2,000 miles of canals and rivers.
The company looks after 1,800 bridges - some 200 years old - and estimates that at least two are struck every week.
It urged drivers to slow down and take more care when driving over them.
It says most drivers leave the scene without reporting the accident.
British Waterways' head of heritage, Nigel Crowe, said whenever you go over a humpback bridge in Britain you are likely to be going over a canal.
"Often officially listed as being of special architectural or historical significance, these bridges have to be painstakingly repaired at considerable cost," he said.
"We're working with the County Surveyors' Society and local authorities to improve signage and road markings, but, frankly, if motorists just slowed down a bit and took more care and attention then we would not be defacing our heritage in this way on a day-to-day basis."
Humpback bridges were built using traditional materials such as lime mortar and locally sourced stone or brick. Damaged sections of bridges are replaced with like-for-like materials, using skills passed down over many generations.