Ten weeks of roadworks are set to start this weekend as essential maintenance is carried out in a tunnel.

A contraflow system will be installed on the A299 Thanet Way between Whitstable and Herne Bay while engineers upgrade the Chestfield Tunnel.

The traffic management system, similar to that used on the M20 during Operation Brock, will be put in place over two phases in a bid to keep traffic moving while work is carried out.

It means one side of the dual carriageway will be split into two single lanes so traffic can flow in opposite directions.

Phase one will be on the coast-bound carriageway, which will run from 8pm on Sunday until 5am on Friday, May 26.

Then from Tuesday, May 30, the contraflow will shift to the London-bound carriageway until 5am on June 30.

A temporary, mandatory 40mph speed limit will be in place in both directions on the stretch between the Golden Hill overbridge and the Thornden Wood Road overbridge, and where indicated by signs.

As well as the contraflow, there will be a series of road closures while workers set up and move equipment.

The A299 Thanet Way between Whitstable, Chestfield, Herne Bay and Herne and Broomfield will be closed in both directions between 8pm and 6am on:

• April 22 for one night

• May 26 to May 30 for two nights

• June 30 for one night, or as signed on site

The alternative routes will be available for coast-bound traffic via the A2990 Thanet Way slip way, A2990 Thanet Way, A291 Canterbury Road and A299 Eddington on slip.

London-bound traffic will be diverted via the A299 Eddington off slip, A291 Canterbury road, A2990 Thanet Way, A2990 Clapham Hill and A299 Whitstable on slip.

A free vehicle recovery service will also be provided.

The project is expected to last ten weeks, starting on Sunday until 5am on Friday, June 30.

The maintenance work includes upgrades to the tunnel's lighting system as the existing fluorescent lamps will be replaced with more energy efficient LED technology in a bid to reduce carbon emissions.

Kent County Council had initially wanted to reconstruct the carriageway at the same time - which would have seen the road shut in alternate directions between the end of April and the end of June.

But in the wake of warnings the closures would have caused traffic chaos, the project was shelved.

Drivers are warned to expect delays in the area while the work is carried out.

Senior county councillor David Brazier said at the time the authority had "listened to people and understood the disruption that these planned, yet essential, maintenance works would cause".

"The lighting replacement in the Chestfield Tunnel needs to happen urgently so we can guarantee the safety of those using it going forward," he said.

"While we had hoped to get the road reconstruction works completed at the same time as the lighting upgrade, the extent of the work is too great to be completed in this timeframe, meaning we will have to revisit at a later date."

County council chiefs say the existing lighting system in the Chestfield Tunnel needs to be replaced as it uses fluorescent lamps, which will no longer be available after August.

The authority is planning to replace the lights and the support system with LED technology.