For thousands of years people have used bridges made from split tree trunks to cross the small streams and rivers that cross Dartmoor. Now the last surviving “clam bridge” is to be closed to walkers because of 21st-century compensation culture, although there is no record of serious injury to anyone using it.

The 20ft-long oak timbers of the bridge in the village of Lustleigh in Devon straddle the River Bovey at a point that has probably been used as a crossing since the Bronze Age more than 2,500 years ago.

The bridge will be sealed off this week despite protests by villagers who say that it is part of Dartmoor’s heritage. It is being closed because no one will accept ownership for fear of being sued if anyone falls off. The bridge would have been demolished but for a campaign by residents of Lustleigh and nearby Manaton. More than 470 people signed a petition to save it.

Engineers from Devon County Council condemned the bridge because its simple design and single handrail did not conform to modern British Standards. Last year they installed a steel bridge, which cost £35,000 and had to be lowered into place by helicopter. The county council then said that it would no longer accept responsibility for repairs to the old bridge, whose timbers need to be replaced every 20 years or so.

Dartmoor National Park Authority agreed to help the two local parish councils to pay for repairs but only if the bridge was closed. It also refused to accept any liability for its use.

Nick Hewison, a member of Lustleigh Parish Council who has campaigned to save the bridge, said: “We have achieved our first objective by preventing the clam bridge being demolished.

The National Park are now offering to help to repair it but the issue is what happens afterwards. It’s the last bridge of its kind on the moor and it is likely that something very similar has crossed the river for hundreds of years, maybe thousands.

“We didn’t think there was a need for the new bridge but the county council say they have to comply with safety standards. They have changed fundamentally an idyllic corner of Dartmoor. Dartmoor National Park has a duty to preserve the beauty, culture and heritage of the moor but they have been more concerned with risk and that threatened to override their responsibilities.

“This is a footbridge in a remote part of Dartmoor only accessed by a very rocky path which is probably more risky than crossing the bridge. The subtlety of its history seemed to escape the officials, who felt that since it was replaced every 20 years it could not be all that old. That is like saying a thatched house is only as old as when its roof was last replaced.

“The bridge is mentioned in the oldest guides to Dartmoor and within 500 yards of it on either side are Bronze Age stone circles.”

A report to the national park authority said that there had been cases of people and dogs falling off the old bridge, which became submerged and impassable at high water levels. It added: “The new bridge provides a safe, accessible route across the river which is appropriate to modern needs.”

You can’t do that . . .

— Sainsbury’s sold Christmas puddings with sixpence coins attached separately because health and safety officials deemed them a choking hazard

— The headmaster of Cummersdale Primary School, in Carlisle, bought six pairs of industrial safety googles for pupils to wear when they played conkers in the playground

— Councillors removed a swing under an oak tree in the Hampshire village of Sheet, even though generations of children had played safely on it since 1897

— Wigston Civic Society members in Leicestershire had to fill out a two-page risk assessment before going rambling. Possible dangers included ploughed fields and rabbit holes

— South Tyneside District Council felled six horse chestnut trees after a young boy was injured falling out of one while trying to grab a conker

— A TUC manual advised managers not to put up mistletoe at a Christmas party in case it encouraged sexual harassment

— Mike Read, a long-distance swimming champion who crossed the Channel more than 30 times, was banned from using his local council pool in Ipswich when it was not supervised

Times recommends

• Energy-saving ideas from switched-on professor
• Rooks are as clever with tools as chimpanzees
• Burping of the lambs blows roast off menu