Moving a proposed roundabout on the Norwich northern bypass would reduce traffic going through Hellesdon, but send more vehicles through Drayton and Thorpe Marriott, council officers have revealed.

The county council has secured �86.5m of the �141.5m cost of the northern distributor road (NDR), which will stretch for 19.5km from Postwick on the A47 to the A1067 Fakenham Road.

But during public consultation on the Northern Distributor Road, Hellesdon Parish Council raised concerns about plans to position a roundabout at Fir Covert Road, rather than at the point where the road meets the A1067 Fakenham Road.

The concern was that a roundabout there would force traffic onto Reepham Road and council officers have drawn up a possible alternative.

In a note sent to parish councils by Mark Kemp, the NDR project manager at Norfolk County Council, he revealed how preliminary studies of traffic models have shown how traffic would be affected if the roundabout were shifted to the west.

He said such a move would cut traffic on Reepham Road, between Drayton Wood Road and Middletons Lane by 5pc, compared to the scheme currently on the table.

Traffic on Reepham Road, between Middletons Lane and the outer ring road would also be cut by 5pc, although there would be a 4pc increase on Drayton High Road between Middletons Lane and the outer ring road.

But the sting in the tail would come in Thorpe Marriott and Drayton, Mr Kemp states that, in 2017, traffic levels would increase by 16pc on School Road through the centre of Drayton and by 8pc through Thorpe Marriott.

Mr Kemp said: 'More detailed plans are being produced to show the traffic effects and will be made available around the end of July.

'Overall, the only drawbacks with this alteration are the increases on School Road and through Thorpe Marriott.

'Further work is in progress to see if these impacts can be mitigated.'

He stressed the alteration is only a suggestion and more detailed further consideration and consultation would be needed before any final decision to modify the scheme.

Meanwhile, this Friday will see another step on the way to the NDR, with a public inquiry pending over plans to close slip roads on the A47 at Postwick.

Those closures are needed, the county council says, to enable access to the new Broadland Gate development and, ultimately, onto the start of the NDR.

A public inquiry is likely to be held in September or October, but ahead of it, a pre-inquiry meeting on the issue will take place at the King's Centre in King Street Norwich, from 10am on Friday.

dan.grimmer@archant.co.uk