Residents of a seaside resort are furious after highways authorities created a 25-mile diversion around roadworks which are just a few yards long.

People in Sidmouth, East Devon, fear the “insane” diversion route could cost the town centre £1 million during the closure of a 75-yard stretch of road.

The diversion hits people travelling to Sidmouth from Honiton, eight miles away, who would normally travel directly there eight miles along the A375. Instead, road signs divert them along a circular route towards Exeter via the A30 and then on to the A3052 – a route three times the normal distance.

The diversion is related to a five-week closure of School Street, in the Sidford area of Sidmouth, while gas firm Wales and West Utilities carries out work.

Richard Eley chairman of Sidmouth chamber of commerce was furious about the diversion. He complained to highways bosses about the 25-mile detour, saying motorists could make a much shorter diversion instead.

“We’re extremely fed up, again,” said Mr Eley. “There are serious implications for the town’s economy.

“A detour of 25 miles is completely unnecessary.

“The cost to Sidmouth is going to be very high. Over five weeks it would cost the town centre more than £1 million – even in January. It’s insane.”

Mr Eley said rather than travelling towards Exeter on the A30, drivers should be directed down the A375 to the Hare and Hounds pub then on to the A3052.

But Highways authority Devon County Council defended the chosen route.

Councillor Stuart Hughes, cabinet member for highways and transportation, said: “Wales and West has signed the agreed diversion from Honiton via the A30 joining the A3052.

“They have also added extra signs to say that businesses are open as usual. This diversion route is suitable for all traffic, including HGVs.”

He added that the council would also be signing an alternative route for light vehicles along the A375 from Honiton, turning off towards the A3052.