People living along the A11 are preparing for years of disruption to their journeys as a set of major roadworks gets under way.

The initial works, which started earlier this month, are the first of two projects to affect the trunk road, the latter of which could last until 2025.

The first project, which is being carried out by National Highways to resurface the A11 at the bypass around Wymondham, will last until June 2023.

Disruption caused by those repairs is expected to worsen in early 2023, when works to upgrade Thickthorn Roundabout are set to begin - if permission is granted for them by transport secretary Grant Shapps.

The expected three to six month overlap between the two projects has sparked concerns from councillors and businesses.

Firms which operate along the route face years of impacts, with the preparatory works for the A11 resurfacing having already caused long queues in parts of Wymondham.

Kevin Hurn, the town’s mayor, said: “There’s been a definite increase in traffic coming through the town. I wouldn’t necessarily say in the town centre, but certainly along what we call the old A11.

“In the mornings, there are extensive traffic queues heading back from the traffic lights to Silfield and along the Harts Farm Road… That’s a definite impact that we’ve seen there.”

Asked about the Thickthorn upgrades next year, Mr Hurn said: “We’re certainly mindful that it’s going to probably have a deeper impact on us at that time, because traffic that would perhaps travel down the A11 to either go east or west along the A47 will be looking for alternative routes, and we don’t want to encourage rat-running across country.”

And on the expected overlap between the two projects he said: “I think probably, for the local community, it would have been better to get one scheme finished before another scheme starts.”

But he added: “The one thing I will say is that the A11 resurfacing has been needed for a long time.

“In most places around Wymondham, you can hear the drone of the concrete from that road, late into the evening, and it is a case of short term pain for long term gain I think, ultimately.”

For drivers journeying from Thetford to Norwich, National Highways is recommending vehicles follow a "dispersal route" down the A140 to Diss, before heading west along the A1066.

Alternatively, drivers will be limited to 40mph along the A11 at Wymondham, with only one lane open in each direction at any one time.

Daniel Starling, commercial manager at haulage company Starlings Transport, said that following the diversion to Diss would mean “an increase in fuel, longer journeys, so that will have a significant impact”.

On the works themselves, he said: “The timing isn’t great, with the A11 and Thickthorn [upgrades] happening at the same time.”

He added however that there would also be a negative side to spreading the works out, as it could mean a more prolonged period of total disruption.

“We use the A14 quite a lot, and that had a lot of roadworks, so from our side, it’s a little bit of short term pain for long term benefit.”

And David Squires, a partner at CC Clements and Son DIY store, on Wymondham’s Fairland Street, said the preparatory works for the resurfacing had already had a big effect on how many people were travelling into the town centre.

“Wymondham is absolutely dead. It was quiet anyway, but since all the roadworks on the A11, fewer people are trying to get into town," he said.

“We had a delivery driver and it took him 20 minutes to travel less than a mile to get into town from the Bridge [industrial] estate.”

He said the congestion was caused by “a mixture of people going along the old A11 and the local people that know the backroads cutting through”.

Asked what measures had been put in place to minimise the impact on Wymondham, a National Highways spokesman said the agency “has worked closely with the local authority to outline our plans and agree on the best traffic management plans to minimise disruption to motorists and local people/businesses”.

On the expected overlap time between the two projects, he said: “It's too early to say but there is a possibility that the two schemes could be on the ground at the same time.

“If that is the case, the A11 concrete road scheme will be winding down as the A47 Thickthorn Junction works are beginning.

“Most of the early work at Thickthorn Junction will be site set up and work off the road network.

“The two scheme teams are in constant dialogue to ensure that if the possibility of both schemes being on the road at the same time, that disruption is kept to a minimum.”