NEWTON Road, Bovey Tracey, may have to be dug up again after a developer accidentally connected surface water drainage pipes to the wrong culvert.
Part of Newton Road was closed for around three weeks during the summer while workmen carried out the work for developer Charles Church (Western) on the Bowdens development, near the Dartmoor Hotel.
It involved the building of 15 dwellings, but residents suspected the drainage work had not been carried out properly and called in the Environment Agency.
An agency spokesman said it had discovered the residents' suspicions were correct.
He said: 'There are two culverts that could have been used, but our requirement was for our own flood defence culvert to be used, not the smaller one.
'It was for flood defence requirements, because the little one has not got the capacity to cope with heavy rainfall.
'We will be taking enforcement action to require the developer to put matters right.'
Bovey Tracey town councillor Anna Klinkenberg said the water surface drainage had been linked to the wrong leat.
'The road was closed for several weeks during the summer and now they will have to do it all over again and the road will be shut once more,' she said.
Lucy Jenner, of TC Communications, for Charles Church (Western), said the company was undertaking investigations to find and correct the problem.